iwa anaerobic digestion sg newsletter_2014-09

IWA Specialist Group on Anaerobic DigestionIssue - September 2014 Newsletter 1

Specialist Group onANAEROBIC DIGESTION

Newsletter: September 2014

CONTENTS

Chairmans note.......................................................................................................................................................2

Contributions to the Newsletter ...............................................................................................................................3

Management comitee of the AD Specialist Group ..................................................................................................4

How to join the Specialist Group on Anaerobic Digestion......................................................................................4

Update from the Task Groups on Anaerobic Digestion...........................................................................................5

News from the world on Anaerobic Digestion ........................................................................................................6

Past and coming conferences and events .................................................................................................................7

PhD and MSc theses on anaerobic digestion .........................................................................................................13

Anaerobic digestion projects .................................................................................................................................34

Anaerobic URL sites .............................................................................................................................................35

News from IWA HQ..............................................................................................................................................36

News from IWA Publishing ..................................................................................................................................38

Disclaimer: This is not a journal, but a Newsletter issued by the IWA Specialist Group on Anaerobic Digestion.Statements made in this Newsletter do not necessarily represent the views of the Specialist Group or those of the IWA.The use of information supplied in the Newsletter is at the sole risk of the user, as the Specialist Group and the IWA donot accept any responsibility or liability.

IWA Specialist Group on Anaerobic Digestion2 Issue September 2014 Newsletter

CHAIRMANS NOTEThere has certainly been a lot happening in the last year since AD13 inSantiago de Compostela, Spain, where we had a fantastic conferenceorganised by the chair Prof Juan Lema and his outstanding organisingand scientific committee. It was the largest AD13 conference yet, with800 attendees, 200 platform presentation, and 400 posters. We alsosaw continuation of the Lettinga award, with the prize awarded to ShivaSalek from TU Delft. Due to the large numbers, and strong activity inthe area, we have now moved this conference to a biennial conference,with AD14 (2015) being in Via del Mar, Chile, chaired by Prof. RolandoChamy, and AD15 (2017) being in China, chaired by Prof. Nanqi Ren,and Prof. Aijie Wang. We will be seeking nominees for AD16 early nextyear, and potential nominees are welcome to ask myself or Henri forinput. We also continue to have a wide range of other specialisedconferences. The Latin America AD conference is in Havana, Cuba, this year 24-27 November and the solidwaste conference lives on as Biogas 2014 in Vienna, Austria, in October this year. We have also seen anumber of additional IWA AD sponsored activities, including formation of a Resource Recovery Cluster, aswell as continued sponsorship of the Physicochemical Modelling Taskgroup and a number of workinggroups. Additional activities listed in this newsletter, including exciting PhD graduates, new books, and thestrong network we have built continue to build and expand on our strong and historic capabilities in thespecialist group. It will be very exciting to see how this area grows to address the new requirements oftechnology and social demands.


CONTRIBUTIONS TO THE NEWSLETTERContributions to the Newsletter should be submitted by e-mail in Ms Word editable format to the NewsletterEditor at [email protected] contributions can be sent to the Group Chairman or to the Group Secretary.Group ChairmanDr Damien BatstoneAdvanced Water Management Centre (AWMC)The University of QueenslandSt Lucia, 4072Australiafax: +61-7-33654726e-mail: [email protected]

Group SecretaryDr Henri SpanjersTU Delft / Civil Engineering and GeosciencesWater management - Sanitary EngineeringStevinweg 1, P.O Box 5048, NL-2600 GA Delft,The NetherlandsT +31 15 2789128, M +31 6 10116953E [email protected]

Editors note: The best care was taken to avoid typing errors during the editing of the contributions receivedfrom SG members. However, should the reader find some mistake please report it to the editor and it will becorrected in the next issue.


MANAGEMENT COMITEE OF THE AD SPECIALIST GROUPCurrent composition of the Management Committee for the IWA Anaerobic Digestion Specialist Group:MANAG. COMMITTEE ROLE PERSON ELECTED E-MAILChair Damien Batstone [email protected] Henri Spanjers [email protected] Editor Jorge Rodrguez [email protected] REPRESENTATIVESNorthern Europe Irini Angelidaki [email protected] Europe Jules van LierAlan Guwy [email protected]@southwales.ac.ukSouthern Europe Jean-Philippe Steyer [email protected] & Eastern Europe Pavel Jenicek [email protected] America Daniel ZitomerToshio Shimada [email protected]@carollo.comCentral America Ivan Moreno [email protected] America David Jeison;Liliana Borzacconi [email protected]@fing.edu.uyMiddle East Afnan DinJorge Rodrguez [email protected]@masdar.ac.aeCentral Asia Makarand M. Ghangrekar [email protected] Aiji WangRaman Saravanane [email protected]@pec.eduAustralia Jurg Keller [email protected]

HOW TO JOIN THE SPECIALIST GROUP ON ANAEROBIC DIGESTIONAll members of IWA are welcome to join the Specialist Group. With the IWA registration, you can indicatewhich Specialist Group(s) you wish to join.If you wish to become member of the Specialist Group on Anaerobic Digestion and you did not have indicatedit on your IWA registration form, please contact the Chairman or the Secretary.You may also directly contact IWA:Hong Li ([email protected])


UPDATE FROM THE TASK GROUPS ON ANAEROBIC DIGESTION

IWA Working Group on Mathematical Modelling of Anaerobic DigestionAD13 very productive for the working group in defining academic and industry needs for next generationmodelling. This will require further review, but there is now a consensus opinion, that specific aspects,particularly around input definition and utilisation of extensions needs clarification.Damien Batstone, Chair of ADM Working GroupIWA Task Group towards a Generalised Physicochemical Modelling Framework (PCM)The Task Group has been working effectively on all three major aspects of gas-liquid, liquid-liquid, andliquid-solid processes, with a draft platform now established, and being applied to whole plant modellingwith the PCM1 replacing all acid-base and precipitation reactions in both activated sludge and anaerobiczones. A number of publications are starting to appear in both conferences and journal publications,including a position paper in Water Science and Technology, and publications at WWTMod 2014 andWatermatex 2013. The Task Group plans to release the final model at Watermatex 2015 in Gold Coast,Australia. Damien Batstone, Chair of PCM Task Group


NEWS FROM THE WORLD ON ANAEROBIC DIGESTION

Winner of Lettinga Award 2013 announcedThe winner of the Lettinga Award 2013, a prize of 25,000 euro, has been announced: Shiva Salek, PhDstudent from TU Delft, with her project proposal: Adding value to Anaerobic Digestion technology byproduction of biobased materials (biocement and fertilizer) and methane enriched biogas using alkalinesilicate minerals.In the winning project proposal, the TU Delft team will investigate the production of biobased materialsby the anaerobic digestion (AD) process when applying minerals for CO2 sequestration. The impact on thebiogas composition and value will be evaluated as well as the cement quality. The economical valuesreceived from production of these materials can further rationalize the costs of CO2 sequestration for climatechange mitigation purposes. The use of minerals in AD seems promising. Other research groups are alsoexploring its potential.The Lettinga Award was initiated in 2001 and is granted every three years. The focus of the call for 2013was on Breakthrough Innovation in Anaerobic Technology. The award committee called for innovativeapproaches, putting anaerobic digestion technologies in the core of the foreseen sustainable society. Thefollowing sponsors were fully convinced of the potential of AD technologies in this development and decidedto support the fifth Lettinga Award: Paques, Nijhuis Water Technology, Waterleau, Veolia Water Biothaneand LeAF.The jury consisted of representatives of the sponsors and academia. From many applications that met thecriteria, the jury had the challenging task to select one winner. Nevertheless, they unanimously agreed. Thewinning proposal was described by some of the judges as:An elegant combination of anaerobic sludge treatment, biobased product and green gas quality.Also, it was described as A very bold proposal; as bold as Gatze Lettinga approached his research topicsin the past. This was the only proposal using AD to produce bio-based products, and not even simple organicbuilding blocks or bio-fuels, but for society crucial inorganic chemicals like cement and fertilizers, whilesimultaneously also developing a very interesting CO2 sequestration technology.The latter will further contribute to the carbon-foot-print reduction which AD already provides sostrongly. The proposal crosses the existing research borders of AD, for which the applicants should becomplimented and should receive support. If successful; many research groups will follow in their footsteps.The proposal is a small project, with potentially large implications.The winner of the Lettinga Award 2013 was announced at the very successful 13th World Congress onAnaerobic Digestion, that took place 25 - 28 June 2013 in Santiago De Compostela in Spain.More information about the Lettinga Award can be found at the LeAF website.http://www.leaf-wageningen.nl/en/leaf/Lettinga-Award.htm


PAST AND COMING CONFERENCES AND EVENTS

The 13th IWA World Congress in Anaerobic Digestion AD1325th-28th June 2013, Santiago de Compostela, Galicia, SpainThe IWA World Congress in Anaerobic Digestion has been taking place tri-annually for already 13 editionswith great attendance levels and success. The AD13 congress aimed in this occasion at attracting as manyresearchers and industrialists working on anaerobic bioprocesses as possible. Previous editions suggestedthat an emphasis in quality of oral presentations was desirable and that was also at the top priority for theorganisers in this event.This strategy proved well accepted by the scientific and technical community as the proposals anddelegates in AD13 reached considerably higher numbers than in any other previous conference: not far from800 attendees from 54 countries and in excess of 740 abstract submissions. The selection of conferencethemes did take into consideration both traditional topics and new tendencies, including interface fields withother technologies. The four invited Plenaries were aimed at exploring new ideas: Biorefinery, AD andClimate change, Innovation in industry and Biomolecular tools for a better understanding of AD processes.Workshops were conceived as a place to discuss controversial topics, such as the role of Microalgae, theopportunities for Biorefinery processes and the Legal and economic constrains. Considering the number andquality of proposals in each topic, the final program was organised in 21 Full Platform sessions (including 8key notes and 97 full platform presentations) and 9 Short presentation sessions (including 108 shortplatform presentations). The fact that only about 15% of proposals were selected for Full platform and other15% for Short platform presentations serves as indicator of the highly competitive peer review and selectionprocess in AD13 when compared to other Congresses.As a novelty, three specialised seminars were organised prior to the Congress on three topics: InnovativePretreatment technologies (in University of Valladolid, Spain), Biomolecular tools applied to AD (inUniversity of Minho, Portugal), and Instrumentation, Modelling & Control (in University of Santiago deCompostela, Spain). 75 early-stage researchers (25 in each seminar) were trained by recognised specialists.A special session (The Three Giants session) was organised as a tribute to three outstanding researchers(Gatze Lettinga, Willy Verstraete and Perry McCarty) whose contributions over the last 40 years have shapedthe current role of anaerobic digestion technologies and their applications. The very important participationof companies as sponsors (1 platinum, 2 gold and 5 silver), exhibitors (8) and contributors to the sessions(almost 15% of the full-platform sessions) must be also highlighted. In addition one of the four plenaries wasdelivered by industry and companies representatives actively participated in the pre-conference workshops.The conference in numbersA total of 776 delegates from 54 countriesattended the AD13 conference in Santiago deCompostela, the largest number in IWA ADconference series. 744 abstracts were received,from which 540 were for consideration for oralpresentation. Among these only 209 wereselected for some form of oral presentation be itkeynote, full or short platform presentation. Atotal of 476 posters were presented at theconference. Three preconference workshops wereheld in three venues in Spain and Portugal.


Key findingsThrough the diverse conference activities, including plenary, platform, short and poster sessions as well asthree targeted workshops, a number of interesting conclusions were drawn out summarised below:- AD profitability can be expanded under the umbrella of the biorefinery concept (making use of VFAs, CO2,etc.) in which AD can play a central key role.- New interesting biomasses have been identified for AD including microalgae and halophyte plants.- Potential has been identified on thermal energy to improve AD profitability.- The impact of molecular tools on AD monitoring and control remains unclear. A gap has been identified onhow those new research tools will be brought into industry as useful and accessible. A gap has also beenhighlighted as remaining between the lack of understanding of the microbial ecology and its role in ADprocess performance for practical purposes.- The synergies between AD and other processes, such as anammox-based systems for nitrogen removal,open new possibilities for expanding the applicability to new concepts for waste and wastewater treatment.- Anaerobic Co-Digestion is as a powerful concept for integrating water and wastewater treatment processes.- A diversity of mathematical models modifications around the well developed ADM1 indicates that there isroom for a next generation model based on ADM1.To be passed on to Practitioners- Importance of innovation, where factors other than technology are required (passion, cooperation, market, etc.).- On the role of market for AD technologies, emphasis on the fact that we, practitioners, must "make" the market.To be passed onto Regulators- A need for holistic approach to face AD processes was identified with the aim at decreasing GHG emissions.- A need to support biogas incentives as a mean to counteract fossil fuel subsidies (through their hugeeconomic externalities) was highlighted.To be subject of IWA Advocacy to international agencies- AD is a clearly very sustainable technology at all levels.

Best AD13 moments: http://www.ad13.org/content/photos


Havana, with its habitual hospitality, has great pleasure to receive warmly in an ideal and warmlyenvironment, the scientific and related-technologies interchange concerning the anaerobic treatment ofwaste matter and the production and use of the biogas in the XI Latinamerican Symposium of AnaerobicDigestion to be celebrated from November 24th to November 27th, 2014. Cuba, as a Latin American countryand faithful exponent of efforts that are carried out in the search of the most balanced and possibledevelopment, already has a tradition of work with the anaerobic technologies. This event is organized by thePolitechnical Superior Institute Jos Antonio Echeverra (CUJAE), together with other Cuban institutionswhich work in themes linked to the anaerobic digestion. During the event the all-comers will have theopportunity to enjoy the attributes that Habana evidences as the Caribbean jewel from the tourist and socialpoints of view. Technical visits will be also organized to places where the anaerobic option to giveenvironmental and energetic solutions has been developed.Themes and Topics.New developments in Anaerobic DigestionMicrobial ecology and molecular biologyBiodegradation of recalcitrant chemicalsBiogas s production and its utilizationRecuperation of energy from waste matterCombustible microbial cellsModelling of anaerobic digestion

Automatization and control of anaerobic digestion processRecuperation of nutrients related with the anaerobicdigestionAnaerobic digestion and biosolids s productionAnaerobic digestion of solid and liquid waste mattersExperiences of plants at industrial scaleAnoxic processes. DenitrificationImportant DatesDeadline for Submission of papers 30th July 2014Notification of acceptance 1st September 2014Deadline for paper submission 1st October 2014Assistance notification 15th August 2014Opening for registration 15th August 2014Early registration 15th September 2014Preliminary Program 30th September 2014Final Program 1st November 2014XI DAAl 2014 24-27th November 2014Organizing Committee HeadDra. Ileana Pereda Reyes Cuba (Chair)Dr. Jos A. Guardado Cuba (Vice-Chair)Dr. Roberto Sosa Cceres - Cuba (Vice-Chair)

Scientific Committee HeadDr. Silvio Montalvo (Chile) (Chair)Dr. Marcelo Zaiat (Brasil) (Vice-Chair)Dr. Gonzalo Ruiz (Chile) (Vice-Chair)More information:http://www.11daal2014.comContact us:Dra. Ileana Pereda ([email protected]) / Dr. Silvio Montalvo ([email protected])


On behalf of the Organizing Committee, we are delighted to invite you to the 14th World Congress on Anaerobic

Digestion to be held in Via del Mar, Chile, during November 2015. This event is part of the IWA Anaerobic

Digestion Specialist Group conference series, which are conceived as an international forum for discussion on state-

of-art of the anaerobic bioprocesses

Topics

The conference will cover a wide range of topics related with the application of Anaerobic Digestion, with the aim

of attracting experts in different fields of knowledge from all over the world. With this wide perspective, the topics

covered by the conference will include:

Reuse of effluent and digestate

Biogas upgrading and management

Microbiology of anaerobic digestion

Resource recovery

New products, novel process configuration and emerging technologies

Modeling, instrumentation and control

Environmental management (life cycle assessment, clean development mechanisms)

Upstream and downstream processes; pre-treatments and post-treatments

Low-tech solutions for developing countries

Important dates

Specialized Courses

Five Specialized Courses will be launched prior to the Conference under following topics:

Climate change and anaerobic digestion (San Pedro de Atacama)

Instrumentation, modelling, control and automation in anaerobic digestion (Santiago)

Pre-treatment for anaerobic digestion (Santiago)

Anaerobic digestion and bio-business (Pucn)

Processes with extremophile microorganisms (Patagonia)

These courses will be held before the Conference. Their duration will be 12 hours in 1.5 days (Thursday 12th and

Friday 13th November 2015) and includes a tour on Saturday November 14th.


Organising CommitteeRolando ChamyPontificia Universidad Catlica de ValparasoLea CabrolPontificia Universidad Catlica de ValparasoAndrea CarvajalUniversidad Tcnica Federico Santa MaraAndrs DonosoPontificia Universidad Catlica de ValparasoMara EspinalNcleo de Biotecnologa CuraumaLorna GuerreroUniversidad Tcnica Federico Santa MaraDavid JeisonUniversidad de La Frontera

Silvio MontalvoUniversidad de Santiago de ChileClaudia PabnUniversidad Adolfo IbezJos Luis CamposUniversidad Adolfo IbezFrancisca RosenkranzNcleo de Biotecnologa CuraumaGonzalo RuizPontificia Universidad Catlica de ValparasoGladys VidalUniversidad de Concepcin

Programme CommitteeRolando ChamyPontificia Universidad Catlica de ValparasoDamien BatstoneThe University of QueenslandJuan Manuel LemaUniversidad de Santiago de CompostelaAdalberto NoyolaUniversidad Autnoma de Mxico

David JeisonUniversidad de La FronteraGonzalo RuizPontificia Universidad Catlica de ValparasoMarta CarballaUniversidad de Santiago de CompostelaJean-Philippe SteyerINRA

Venue

For its privileged coastline, Via del Mar is one of the most prominent tourist destinations in South America and

for a decade it has become one of the major cities of the southern hemisphere to receive conferences, events and

conventions. The reasons for this are the high quality of its conference centers, variety in accommodations,

excellent national and international connectivity, and especially, the warmth and professionalism of its community.

Via del Mar is located one hour far from the countys principal airport and only ninety minutes far from

Santiago. All of them are connected by modern roads and highways.

The 14th Anaerobic Digestion World Congress website is already available for those who need accuracy

information about this world event. You will find full information about topics, special grades, organizing

committee, scientists guests and step by step forms of application on AD14, in the official website

www.ad14chile.com


Progress in Biogas IIIWe would like to welcome you to our International Conference "Progress in Biogas" held for the 3rd time inGermany, September 10-12th. More than 80 experts on biogas from almost 30 countries representing all thecontinents will discuss the progress in biogas at the Haus der Wirtschaft in Stuttgart this September.In addition we will offer a 4-day International biogas Study Tour through Germany with focus on WASTEDIGESTION the following week of the conference 15-18 September. www.biogastraining.comDuring the conference a practitioners forum, an Oral-Poster-Session with more than 20 speakers, posterssessions and an exhibition will take place. In the exhibition companies and organizations will present theirproducts, services and technical innovations to the international audience experts. According to theattendance to the last two conferences, we expect to have about 400 participants.More information at http://www.progress-in-biogas.com/The 12th annual short course on Anaerobic Treatment of High-Strength Industrial Wastewill be held September 10-11, 2014 at Marquette University in Milwaukee, Wisconsin, USA. The course isdesigned for both practitioners and student to learn the fundamentals and full-scale application of anaerobicbiotechnology. This years keynote speaker is Dr. Jean-Philippe Steyer, Director of the EnvironmentalBiotechnology Laboratory, French National Institute for Agricultural Research (Narbonne, France). Otherspeakers will include Dr. Daniel Zitomer (Marquette University) and Dennis Totzke (Applied Technologies,Inc.). Presentations will address anaerobic microbiology and chemistry fundamentals, anaerobic processoperation and design, biogas conditioning and utilization, construction/start-up guidelines and case studiesof operating anaerobic treatment systems. For the course schedule/content and other information, seehttp://www.marquette.edu/ANT after June 1, 2014 or email Daniel Zitomer ([email protected]). Alimited number of fellowships are available to cover registration costs for graduate students studyinganaerobic biotechnology. Students interested in applying should contact Dr. Zitomer.


PHD AND MSC THESES ON ANAEROBIC DIGESTION

Modeling biotechnological processes under uncertainty.Anaerobic digestion as case study

PhD by ivko Junic-Zonta ([email protected])Institution

GIRO Joint Research Unit IRTA-UPC

Universitat Politcnica de Catalunya. UPC BarcelonaTECH

Supervisors

Prof. Xavier Flotats. Department of Agrifood Engineering andBiotechnology. UPC BarcelonaTECH, Castelldefels (Spain)[email protected]

Dr. Albert Magr. IRSTEA, Rennes (France).

[email protected]

PhD dissertation: http://hdl.handle.net/10803/97039

Abstract: Any approximation of the observed reality within an explicit model necessary implies uncertainty, which

should be characterized and quantified to build confidence over model results. Uncertainty associated with model-

parameter and its implications for bio-process optimization are of main concern in this PhD work. As a bio-process

case study, the anaerobic digestion is considered for modeling. The production of biogas by controlled anaerobic

digestion could be a profitable activity, apart of being a renewable energy source. However, the margins to improve

this technology are wide. Anaerobic co-digestion with two or more input materials is a way to make low biogas

yield biomass applicable at industrial scale. Among the possible co-substrates, lipids-rich wastes are attractive for

their high energetic potential. The main limiting factor for this strategy is the inhibition of anaerobic digestion by

long chain fatty acids. Modeling provides a useful approximation of the complex and delicate microbiology activity

of this anaerobic digestion system. The underlying goal of the PhD project is to improve biotechnological processes

with the aid of modeling and uncertainty analysis. With this goal in mind, a general purpose, user-friendly,

simulation environment called virtual plant (VP) was build and applied to anaerobic co-digestion and activatedsludge modeling. Within the VP tool, new core dynamics of the long chain fatty acids (LCFA) inhibition process

were proposed and tested and different inferential procedures for the estimation of parameter-uncertainty were

compared. Finally, a proposed multi-criteria analysis under uncertainty and multiplicity was applied to an industrial

anaerobic co-digestion biogas plant. In conclusion, the developed VP toolkit was found reliable and user-friendly

when modeling activated sludge and anaerobic digestion systems. The proposed LCFA-inhibition model was able

to reproduce correctly the experimental data at hand and enabled its interpretation. However, uncertainty estimation

of parameters and falsification of the proposed model of LCFA-inhibition are still missing. The Bayesian procedure

was proved useful when addressing the estimation of parameter uncertainty of anaerobic digestion and activated

sludge models. A considerable improvement in the operation efficiency and reliability of an industrial biogas plant

was possible within the proposed multi-criteria analysis. However, future work is needed to improve the procedure

of elicitation of the inputs for this multi-criteria analysis and decrease its computational burden.


Study of methods for the improvement of the anaerobic digestionof lipids and long chain fatty acids

PhD by Rim Affes Salah ([email protected])

Institution



Supervisors


Dr. Jordi Palatsi, GIRO program, IRTA, Caldes de Montbui (Spain)[email protected]

PhD dissertation: http://hdl.handle.net/10803/116545

Abstract: Lipid-rich waste and wastewaters have a high energy potential, however efficient methane recovery with

conventional anaerobic digestion technology is not easy to achieve because of a wide assortment of operational

problems mainly related to the accumulation of long chain fatty acids (LCFA), products of lipids hydrolysis, in the

system. The objective of the present dissertation is to test and to evaluate new methodologies and strategies to

improve the anaerobic digestion of high-strength lipid waste. The results of studies submitting anaerobic reactors to

increasing concentrations of lipids/LCFA underlined the importance of the adsorption of LCFA onto the microbial

cell membrane as limiting factor, guiding further research to found new technical approaches in order to control the

biomass-LCFA adsorption dynamics. The use of inorganic adsorbents to capture LCFA prior to the anaerobic

digestion process or the application of sequential low-energy ultrasonic pulses in order to control the adsorption-

desorption kinetics were tested with interesting results. However, the effectiveness of these strategies was limited

by the proportion of inorganic adsorbent/LCFA and the cumulative damaging effect of ultrasonic treatment over

biomass, respectively. Efficient conversion of complex high-strength lipid waste to methane was proved to be

possible in a novel reactor system configuration combining saponification pre-treatment and digested solids

recirculation to the anaerobic digestion process, to increase solids retention time. A start-up step consisting on

pulse-feeding cycles of the fatty waste prior to the semi-continuous process promoted an adapted microbial

community for LCFA mineralization. The feasibility of this system configuration for solid slaughterhouse fatty

waste was evidenced at lab scale reactors, reaching organic matter removal efficiencies higher than 90%. The

comparison of this configuration with systems without saponification or without digested solids recirculation

confirmed the synergistic effect of both strategies. The use of high throughput sequencing approach (454-

pyrosequencing) to characterize the evolution of the biodiversity and the phylogenetic structure of the microbial

community during the operation of the tested configurations concluded that a selection of a defined functional

acidogenic population (-oxidizers) was induced by substrate pretreatment. Contrary, the solids recirculationresulted in an enrichment of the methanogenic biodiversity, mainly of hydrogenotrophic archaea. Based on the

satisfactory results obtained with the strategies studied in the present dissertation, it is expected that lipid-rich waste

valorization will be a real alternative to increase renewable energy production through anaerobic digestion process.


Anaerobic digestion of animal by-products. Pre-treatments and co-digestion

PhD by ngela Rodrguez Abalde ([email protected])

Institution



Supervisors


Dr. Beln Fernndez, GIRO program, IRTA, Caldes de Montbui (Spain)[email protected]

PhD dissertation: http://upcommons.upc.edu/?locale=en

Abstract: The meat sector is associated with the generation of large quantities of animal by-products not intended

for human consumption (ABPs). The increasing demand of renewable energy sources and reuse of wastes require

good technological solutions for energy production such as anaerobic digestion (AD), which is included in the

current European regulation as one of the allowed methods to valorize ABPs. Due to their composition, with high

fat and protein content, ABPs can be considered good substrates for the AD process, according to the high potential

methane yield. Although slow hydrolysis rates and inhibitory process have been reported, with a suitable pre-

treatment to improve particulate materials solubility and/or co-digestion process of complementary materials the

anaerobic digestion can be improved.

Hence, the aim of this thesis was to evaluate the feasibility of different ABPs for AD. Emphasis was placed on the

effect of pre-treatments on the organic matter, methane yield and methane production rate. Within this scope,

thermal (pasteurization and sterilization) and high pressure pre-treatments (200, 400 and 600 MPa) were applied.

Thermogravimetric and spectroscopy techniques where used to determine the effects on the organic matter besides

to a classical characterization. The effects on the methane yield and methane production rates, including the

disintegration parameters, were obtained by means of batch test with different inoculum to substrate ratios (ISR).

The suitability of ABP for anaerobic digestion was confirmed with samples from different origin (poultry and

piggery slaughterhouses) but the results showed that methane yield depends on the relative substrate composition

(proteins, fats and carbohydrates), especially when a thermal pre-treatment is applied. The results of the

disintegration kinetics determination underline the positive effects on the methane production rate being increased

after pasteurization. In parallel, continuous co-digestion of pasteurized ABP with pig manure and glycerin was

studied, optimizing the production of biogas by controlling the composition of the mixture of wastes to be treated.

Changes in the microbial populations (monitored by DGGE) were determined. In conclusion, the production of

biogas from SANDACH has proved to be feasible by improving their AD by means of co-digestion with other

wastes which balance the composition and by thermal pretreatment, being its effectiveness highly dependent on the

composition of proteins and carbohydrates.


Relating methanogen community structure and function in anaerobic digesters

PhD by Benjamin T.W. Bocher

Department of Civil & Environmental Engineering, University of Wisconsin Platteville, 1 University Plaza,Platteville, WI 53217 ([email protected]) +001 414.254.0297Marquette University, 2012

Advisor: Daniel Zitomer, Ph.D., P.E., Department of Civil, Environmental, and Construction Engineering,

Marquette University, P.O. Box 1881, Milwaukee, WI 53233 U.S.A. ([email protected])

A deeper understanding of how microbial community structure relates to process function would help improve

anaerobic digester design. This dissertation describes both qualitative and quantitative relationships between

anaerobic digester function and microbial community structure. Community structure was characterized using

banding pattern intensities from denaturing gradient gel electrophoresis (DGGE) for the mcrA gene of

methanogenic Archaea.

The first project compared a single-stage continuously mixed stirred tank reactor (CSTR) and staging with an

acidogenic CSTR followed by a methanogenic CSTR. After seeding with the same biomass, these unique process

configurations exhibited different function and qualitatively different methanogen communities. Compared to a

single-stage CSTR, staging increased the maximum rate of methane production by 41, 26, and 57% with

propionate, acetate, and hydrogen, respectively. Additionally, the staged digester produced 10% more methane and

achieved 10% greater volatile solids (VS) destruction.

The second project also provided a qualitative relationship: methanogen community structure impacted digester

function upon bioaugmentation. Specific methanogenic activity (SMA) with propionate statistically increased (up

to 57%) in six of nine bioaugmented anaerobic cultures. These increases correlated to methanogen community

structure above the 98% level (rs = 0.770) using Spearmans Rank Correlation Coefficient (two-tailed).

In the third project, a quantitative structure-activity relationship (QSAR) was established between methanogen

community structure and two activities using multiple linear regression (MLR). Two different QSARs were

predictive of SMA values with propionate (q2 = 0.52) and with glucose (q2 = 0.56), respectively. A MLR model

may be applicable to other biological communities when trophic redundancy and a ubiquitous gene are present and

when a linear model is appropriate.

Greater understanding of anaerobic digester microbial communities is possible using these QSARs. This research

serves as a template that can be used to construct additional QSARs for other complex microbial communities in

engineered systems.


Bio-carbon Source Recovery and Sustainable Reutilization of Waste ActivatedSludge

By Aijuan Zhou

Harbin Institute of Technology

With the development of the economy, the amount of municipal wastewater discharge increased year by year. At

the end of 2008, many municipal sewage treatment plants have been put into operation with a daily capacity of

averaged approximately 66,998,000 m3 in China. However, large amounts of waste activated sludge production

associated with sewage treatment process, including proliferation of microorganisms and adsorbed organic

compounds inside, will bring secondary pollution to the environment without dispose. In 2008, residual sludge

production up to 18 million tons a year ( 80% moisture content ) , followed by a rapid growth of an annual rate of

10% , its treatment and disposal costs typically account for 20 to 50% , even 70% of the total operating costs of

sewage treatment. (..)

The comparison between chemical and biological surfactant addition on sludge acidification and fermentation

performance were investigated. The acidification and fermentation of WAS were apparently enhanced by external

rhamnolipid (RL) addition, which were better than that obtained in sodium dodecyl benzene sulfonate (SDBS) and

sodium dodecyl sulfate (SDS). The concentrations of VFAs for carbohydrate conversion were 1648, 4890 and 5972

mgCOD/L in SDBS, SDS and RL pretreatment tests, respectively. Pyrosequencing analysis based on the bacterial

16S rRNA gene showed that dominant population in different surfactant pretreatment tests was significantly

changed. Hierarchical cluster analysis further revealed that SDBS and control samples had a similar bacterial

community composition, although partly of genus were changed. Megasphaera was only observed in RL samples,

which was related to the production of acetic (HAc), propionic (HPr), butyric (HBu) and valeric (HVa) by

carbohydrate and lactic acid fermentation. Oscillibacter was proved had a direct relationship with D-glucose and

partly pentaglucose metabolism and VFAs production.

()

WAS fermentation liquid enriched VFAs with different pretreatments was used as substrates for hydrogen

production in microbial electrolysis cell (MEC) to achieve efficient utilization. The effects of substrates

concentration by bi-frequency ultrasonic pretreatment on hydrogen production in MEC were investigated. The

experiment tests with twice diluted SFL2 obtained the maximal H2 yield (1.2 mL H2/mg COD), the total H2

recovery rate reached 10 mmol H2/mg VSS from WAS. Meanwhile, the effects of different surfactant pretreatments

on hydrogen production in MEC were also investigated. Considering the utilization of partly substrates (higher than

C4 VFAs and protein), the degradation rate with SDS addition was higher. Lower than C3 VFAs and carbohydrate

was utilized efficiently with RL addition. Compared with the results of H2 yield and energy efficiency, biological

surfactant was better than chemical surfactant on hydrogen production in MEC. The maximal H2 yield (0.92 mL

H2/mg COD) was obtained in biological surfactant addition test, which was 0.01 and 0.75 mL H2/mg COD in

SDBS and SDS addition tests. The corresponding energy efficiency were 2.0% for SDBS, 51% for SDS and 64%

for RL, respectively.


Azo Dye Containing Wastewater Treatment in Anaerobic System Coupled withBiocatalyzed Electrolysis module

By Dan Cui


Azo dyes are the largest chemical class of dyes and are frequently used for textile dying and paper printing industries

due to cheap costs, firmness, and a variety of colors compared to natural dyes. However, azo dyes are highly toxic and

persistent to biodegradation. Besides, the intensive color of dye-containing wastewater leads to severe aesthetic

problems and obstructs light penetration and oxygen transfer into water bodies, adversely affecting aquatic life. For

these reasons, the color removal from dye-containing wastewater is one of major concerns in China where textile

industry has grown exponentially in recent years. Azo dyes should be removed from wastewater before being

discharged to water body. More recently, Bioelectrochemical system (BES) is emerging as a promising technology in

which microorganisms function as catalysts to convert chemical energy into electrical energy. BES has been tested for

many potential applications besides electricity generation, including biohydrogen production, metal reduction and

recovery, desalination, organic products synthesis and treatment of various wastewaters. In this study, we developed

an economical BES lacking membrane (an up-flow biocatalyzed electrolysis reactor (UBER)) for treating azo dye

wastewater. Alizarin Yellow R (AYR) was used as a model dye. With the supply of external power source 0.5 V in the

UBER, AYR decolorization efficiency reached up to 94.8 1.5%. (.) Decolorization efficiency was improved withincreasing cathode size in UBERs, but AYR removal rate and current density were not increased in proportion to

cathode size, mainly due to the limitation of anodic reactions. AYR decolorization rate was optimized at a cathode size

of 90 cm3 in an UBER where the charge transfer resistance Rct (39.5) was minimal. AYR and its reductive productswere further mineralized in the subsequent aerobic bio-contact oxidation reactor (ABOR). We assessed the effect of

hydraulic retention time (HRT: 6.5 h, 4.5 h, 3.5 h, 2.0 h) on the removal of residual by-products (PPD) and (5-ASA) in

the ABOR. The concentrations of PPD and 5-ASA decreased down to 0.28 0.01 and 0.27 0.03 mg L-1,

respectively, in an optimum HRT 3.5 h. Decolorization efficiency andCOD removal efficiency was 93.8

0.7% and 93.0 0.5% in the combined process of UBER and ABOR in overall HRT 6 h (HRT 2.5 h in UBER +

HRT 3.5 h in ABOR). The Chroma in ABOR effluent was 80 times. Based on the design of UBER, we developed a

new system integrating UBER with ABR by installing UBER module into each compartment of ABR (called, ABR-

BES) and tested this novel process at a small pilot-scale for the treatment of azo dye (AYR) wastewater. The ABR-

BES was operated without and with external power supply to examine AYR reduction process and reductive

intermediates with different external voltages (0.3, 0.5 and 0.7V) and hydraulic retention times (HRT: 8, 6 and 4h).

The decolorization efficiency in the ABR-BES (8h HRT, 0.5V) was higher than that in ABR-BES without electrolysis,

i.e. 95.11.5% versus 86.96.3%. Incorporation of BES with ABR accelerated the consumption of VFAs (mainly

acetate) and attenuated biogas (methane) production. Higher power supply (0.7V) enhanced AYR decolorization

efficiency (96.41.8%), VFAs removal, and current density (24.1A m-3 TCV). Shorter HRT increased volumetric

AYR decolorization rates, but decrease AYR decolorization efficiency. The novel ABR-BES with membrane-free

provided a new concept for BES scaling-up to energy-efficient treatment of azo dye wastewater.


Selective Reduction of Nitrobenzene in Bioelectrochemical System and theFeasibility of Energy Loop Compensation

By Haoyi Cheng


Nitrobenzene (NB), one of typical recalcitrant organic compounds, is reported as possible mutagens, teratogens or

carcinogens and has been listed in 58 Chinas priority control organic pollutants. As the electrophilic effect of nitryldecreases the electron density of the benzene, NB is only to a limited extent degraded in aerobic biological

processes. An effective strategy is to transform NB to aniline (AN) first, which is considerably easier mineralized

than NB. The electrochemical reduction of NB is an efficient and controllable approach, however, the conventional

process suffer from the requirement of special electrode materials or noble metal catalysts to achieve the selective

transformation of NB to AN, which limited its application in practice. Recent developed bioelectrochemical system

(BES) is proposed as a perspective process in wastewater treatment, since bacteria, as catalyst, hold the inherent

advantages of low-cost, self-regeneration and evironment-friendly. The present study demonstrated bacteria can use

the cathode as the sole electron donor to selective reduce NB to AN. The introduction of organic carbon to

biocathode further enhanced this selective transformation capability. Based on above findings, the study went on

developing novel process that enabled energy internal loop compensation by recovery energy from aniline at

bioanode. The important role of oxygen in the process was demonstrated and the involved mechanism was than

discussed.

When cathode was served as sole electron donor, the transformation efficiency and rate from NB to AN was

dramatically increased with microbial catalysis. 93% of AN formation efficiency was achieved in biocathode at the

cathode potential of -0.4 V, which was 6.16 times as high as that obtained in abiotic cathode. In addition, the

maximum accumulation of toxic nitrosobenzene (NOB), the intermediate during NB reduction to AN, was

decreased by 38.7% in biocathode compared to that in abiotic cathode. Cyclic voltammetry (CV) revealed that an

unidentified redox compound with the midpoint potential around -0.315 V could be responsible for the electron

transfer from cathode to bacteria. Based on the apparent first-order kinetic model, biocathode was suggested to both

catalyze the reduction of NB and NOB. The corresponding apparent first-order kinetic constant was increased by

62% and 100%, respectively. Moreover, the community of the inoculum and the biocathode sample was analyzed

based on the pyrosequencing. The results indicated microbial community was changed dramatically under the

evolutionary pressure provied by cathode served as sole electron donor. The predominant bacteria in biocathode

community consisted of Rhizobium sp., Leucobacter sp., Achromobacter sp., Mycobacterium sp., Dysgonomonas

sp. and Pseudomonas sp.. The functions of selective nitrobenzene reduction, carbon fixation and the possible

cathodic extracellular electron transfer in the microbial community might feature the catalyzed selective reduction

of NB to AN in biocathode. (.)

To achieve the energy internal loop compensation, the process of NB reduction with electrons partial fed-back from

AN oxidation was proposed. The saved external electron donor and internal loop compensated energy was

estimated as 22%~53% and 17%~40%, respectively, based on the experiment results and the thermodynamic and

stoichiometric calculation.


A Novel Approach for Efficient Biomethane Production from Bio-wastes in ACompact System

By Haoyu Wang


Organic solid wastes are worldwide produced in high amounts and increasingly considered as bioenergy-container

more than as a waste product. As a method to convert organic wastes into biofuels, anaerobic digestion (AD) can

benefit to ease the worldwide environmental problems and fossil fuel constraints. However, the complexity and

recalcitrance of organic solids make the hydrolysis process inefficient and thus a rate limiting step to many AD

technologies. Although much effort has been made to enhance the hydrolysis efficiency, such as applying extreme

temperature, different pH conditions or using enzyme(s) to catalyze the hydrolysis process, most of those studies

aim to treat energy-profitable crops, while less focus has been paid to waste solids. In this study, a novel method to

efficiently convert organic solid wastes into methane is proposed and proved to be more favorable compared to

conventional methods. Brewery spent grain (BSG) and pig manure (PM) were used to test the feasibility and

efficiency of the method. BSG and PM were enzymatically hydrolyzed and solubilized, after which the

hydrolysates were used for AD using different bioreactor designs. It was shown that complex organic solids, such

as cellulose, hemicellulose, proteins and lipids are efficiently hydrolyzed and provided easy biodegradable/bio-

convertible influents for the subsequent AD step. Methane production from the BSG and PM was eventually about

56% and 45% of their total COD content. High organic loading rates (OLRs), reaching 19 kgCODm-3d-1 and 21kgCODm-3d-1 were achieved for the expanded granular sludge bed (EGSB) type lab reactors, fed with BSG andPM, respectively. This is 5-7 times higher than usually obtained with direct digestion of raw materials. The current

approach represents a promising technique for industrial-scale treatment of organic solid wastes with a small

footprint.

Harvesting bioenergy from organic biomass have been proven to be a promising alternative to fossil fuels.

Although the liquid biofuels (e.g. bioethanol or biodiesel), harvested from agro-energy feedstocks bring

considerable profit, there have been some criticism due to its potential threat to the global food balance. Some

wastes, such as spent grains and pig manure, are high energy-containing organic solids and can be used to produce

energy carriers like methane. Traditional methanisation approaches, such as continuous anaerobic digesters, require

lengthy residence times because of (1) slow (rate limiting) hydrolysis and (2) easy loss of slow growing

microorganisms. This work introduces a novel method to methanise the solid bio-wastes spent grains and pig

manure at a high rate and high yield by coupling a separate, enzymatic hydrolysis step to a high efficiency

methanisation system. This method could be suitable for other types of organic solid wastes, such as the organic

fraction of municipal wastes, excess sludge of wastewater treatment, bio-energy containing plants or various

poultry manure.


Processes Control on Partial Nitritation Coupled with Anaerobic AmmoniumOxidation and Its Application to Nitrogen Removal from Landfill Leachate

By Huosheng Li

South China University of Technology

Leachate generated from landfill contains high concentrations of ammonium and organic compounds, varies

significantly in composition and flow rate, thus making its treatment energy-gobbling and highly expensive when

using conventional nitrification and denitrification processes. Due to the high cost-effectiveness and efficiency,

combined partial nitritation (PN)-anaerobic ammonium oxidation (ANAMMOX) process, is a promising alternative

to conventional nitrification and denitrification for nitrogen removal from landfill leachate. However, the PN-

ANAMMOX technology has not yet been fully investigated; there have still been some barriers remained to be

solved. Both ammonia oxidation bacteria (AOB) and ANAMMOX bacteria (AnAOB) are slow growers, and are

susceptible to the variation in wastewater compositions and operational conditions, thus resulting in a slow reactor

startup and a difficult process control and a frequent instability in operation. The overarching goal of this research

was to solve the above issues: to investigate the fast startup, loading enhancement and process control of the PN

and ANAMMOX units, to examine the rules of the process control on combining PN-ANAMMOX by means of

two-stage and one-stage modes. The results are listed as follows.

(1) By using conventional fixed-time control in a sequencing batch reactor (SBR), partial nitritation of landfill

leachate was achieved under both intermittent and continuous aeration modes. The adjustment of total air flux

(TAF)/ influent loading rate (ILR) ratio was observed to be effective to inhibiting nitrate formation. The effluent pH

was found to be an indicator for effluent NO2--N/NH4

+-N molar ratio. Due to more granules formed in the reactor

operated under intermittent aeration mode, the nitrogen and COD removal performance were superior to those

observed in continuous aeration mode.

(2) During the PN experiment in an SBR with a 10 times bigger volume (50 L), combination of partial nitritation

and denitrification was achieved by using flocculent activated sludge. Inhibition of nitrate formation can also be

achieved by adjusting the TAF/ILR ratio; effluent pH was also observed as an effective indicator for effluent NO2--

N/NH4+-N molar ratio. The analysis of the state in an SBR cycle showed that simultaneous nitrification and

denitrification occurred in the first aeration stage.

(3) Endpoint pH control technique was used in the PN-SBR system for landfill leachate treatment by combination

of partial nitritation and denitrification, resulting in a stable performance during long-term operation. Dynamically

setting a suitable endpoint pH was the key to achieving optimal effluent NO2--N/NH4

+-N molar ratio. Air flow rates

at 0.8, 1.2 and 1.6 m /h had unnoticeable effect on effluent NO2--N/NH4

+-N molar ratio. Reaction temperatures at

30C, 33C and 36C had also unnoticeable effect on effluent NO2--N/NH4

+-N molar ratio. Influent flow rate had

no obvious effect on effluent NO2--N/NH4

+-N molar ratio as well.

(.)


Study on the Full-Scale Experiment of Integrated Sludge Thickening andDigestion Reactor Treating Sewage Sludge

By Jiang Li

Chongqing University

Currently, sludge treatment and disposal has become one of the urgent problems presented in the field of

wastewater treatment, especially in small towns of China. Due to the unstable quantity and quality of inflows in

wastewater treatment plants (WWPTs) in small towns, which result in a low sludge production and the unsteady

properties, it is required that some simple, cost-effective and innovative sludge treatment technologies and facilities

should be developed. Aiming at the problems in sludge treatment in small towns, our research team has developed

an integrated sludge thickening and digestion reactor. Three generations of the reactor have been modified and

improved successfully through investigations of small-scale experiments. Moreover, on the basis of the numeric

simulation and optimization of flow condition, the pilot-scale reactor has been developed. Study on the pilot-scale

experiment has been carried out in a WWPT. Optimized operation conditions have been obtained and the

disadvantages of the reactor have been analyzed simultaneously. After improvement of the pilot-scale reactor, the

full-scale reactor has been developed and studied in Dadukou WWPT of Chongqing. The efficiency of sludge

thickening and digestion, stabilization of heavy metals and macrobiotic population diversities in the full-scale

reactor have been investigated and studied. The results are shown as follows:

The flow test is carried out to study the characteristics of flow condition in the pilot-scale reactor using NaCl as

tracer. The results illustrate that the dimensionless variance (2) in the lower section and base of inner reactor are0.63, 0.67 and 0.34, 0.44 in the upper section and mid-upper section under no gas recirculation. The inner reactor

from upper section to base under 8L/min, 12 L/min and 16 L/min are 0.60-0.63, 0.64-0.68, and 0.65-0.66,

respectively. And the flow condition has a tendency to a mixing flow condition completely. For the purpose of

completely mixing in inner reactor and the operation cost, 12.0L/min of gas flow has been adopted in the operation

test of the pilot-scale reactor. ()

The microbial population diversity in the full-scale reactor has been investigated by the PCR-DGGE technology.

The results illustrate that microbial diversity distribution is shown in the reactor. Amount of microbial in the area of

outlet sludge is more than that in the inner reactor, so the outlet sludge can be recycled into the inner reactor to

increase the amount of microbial. The microbial population diversity is similar under different inlet sludge ratios. In

fact, the only difference is the quantity. It is concluded that the microbial population diversity do not change with

inlet sludge ratio. The microbial population diversity is more than that in the outer reactor, and it can be concluded

that there is functional difference between the inner reactor and outer reactor. The same microbial populations exist

both in the inner reactor and anaerobic digester, but four special microbial populations are found in the inner

reactor. The results from this study can be the basis of practical application for the integrated sludge thickening and

digestion reactor, including design, start-up and operating of reactor, which will be of great significance to

engineering application of integrated sludge digestion and thickening processing technology in the future.


Research of Microbial Community Eclogy and Thetrophic Link During AcidogenicFermentation

By Jin Wang

Jiangnan University

Acidogenic fermentation is a critical step in the process of anaerobic fermentation of organic matter. Volatile

organic acids (VAFAs) is not only one of the main intermediate product, but also an important raw material for the

organic chemical industry. Productions of VAFAs is closely contact with organic matter degradation and biogas

generation. Hydrolysis microorganisms & acidogenic microorganisms, methane-producing microorganisms &

VFAs-producing microorganisms have complex mutual camps relations. In recent years, high-throughput

sequencing technology has been used by a growing number of micro-organisms workers and has been a very

promising biotechnology. Unlike traditional sequencing methods with nucleotide specificity of the DNA fragments,

high-throughput sequencing technology can parallel sequence to hundreds of thousands to millions of DNA

molecules. In VFAs-producing reactor, VFAs -producing microorganism population ecology was study. The

methanogenic inhibitor addition which does not affect the acid-producing microorganisms, volatile fatty acids and

other intermediate metabolites is a common technique method.

For our study, VFAs-producing microorganisms from the population and community levels in the anaerobic

fermentation was used by environment molecular microbial ecology technology, such as high-throughput

sequencing, the population structure of the VFAs-producing bacteria was determined, the contribution of various

flora acetic acid was clarified, the yield of VFAs production was enhanced by flora structure and regulation. On

these basis the optimal operating conditions of the process was identified, and a dynamic model was constructed.

This study should enrich the theory and application of the anaerobic fermentation process.. The main findings are as

follows:

1 Glucose-degrading microorganisms in activated sludge under methanogenic conditions. Monosaccharide

degradation is an important step in the anaerobic fermentation of organic matter, the case for BES inhibition of

methanogenesis, anaerobic sludge glucose degradation plays a critical role in microbial less. The modes of

anaerobic acid production and the production of methane was studied by DNA-SIP, clone library and high-

throughput sequencing technology, The results showed that Clostridia was dominant in the inhibition of methane-

producing anaerobic fermentation, whose abundance accounted for 51.88% of the total bacteria and Bacilli was

dominant in the inhibition of methanogenic anaerobic fermentation, whose abundance accounted for 50%; The

abundance of Peptococcaceae, Syntrophomonadaceae and Syntrophobacterale genus in the methanogenic culture is

significantly larger than the culture of inhibit methanogenis. The trophic link between hydrogen-producing

acetogenic bacteria and methanogenic bacteria play an important role in anaerobic methane-producing system.

(.)

5 The kinetic model of the system of homoacetogens enrichment.

The kinetic model of homoacetogens enrichment based on ADM1 model was builded and the kinetic model was

simulated and verified to experimental data. The result showed that the this model can be used as the basis to design

the process of homoacetogens enrichment.


Performance and Characteristics of Compartmentalized Anaerobic Reactor

By Junyuan Ji

Zhejiang University

Energy shortage and environmental pollution are two major survival pressures in the world,and the application of

anaerobic digestion technology to organic wastewater treatment can eliminate pollutants as well as produce

bioenergy, which will play a great role in energy-saving and emission-reduction. Anaerobic reactor is the core of

digestion technology, the research of high-rate anaerobic reactor have forcefully promoted the development of

anaerobic digestion technology.

Compartmentalized Anaerobic Reactor (CAR) is a novel high-rate anaerobic reactor designed by our laboratory. In

this paper,the performance, vertical distribution, early warning and flow patterns of CAR were investigated and the

toxicity of pharmaceutical wastewater containing antibiotics and its anaerobic digestion intermediates was assayed.

The main achievements were as follows.

(1) Having revealed the working performance of CAR.

CAR could reach a high volumetric efficiency. The organic loading rate, volumetric COD removal rate and

volumetric biogas production were 100.46 gCODL-1d-1, 84.35 gCODL-1d-1 and 57.00 LL-1d-1, respectively.

CAR could provide a greater driving force for the anaerobic digestion reaction. The average concentrations of

COD and volatile fatty acids (VFA) in a high-rate CAR were 2447 mg L-1 and 1638 mgL-1, respectively, which

were 18.49 and 37.52 times as high as their counterparts in a common-rate CAR.

The performance stability of CAR at high loading rate was worse than that at common loading rate. At normal

loading rate, the fluctuation of effluent COD concentration and volatile fatty acids (VFA) concentration was

synchronous with that of influent COD concentration. The average relative standard deviation of effluent COD

concentration and VFA concentration was 24.57% and 23.03% respectively, while that of influent COD

concentration was 23.92%. nevertheless, the fluctuation of effluent COD concentration and VFA concentration was

large as compared with regard to that of influent COD concentration at high loading rate. (.)

(4) Having assayed the acute toxicity of pharmaceutical wastewater containing antibiotics and its anaerobic

digestion intermediates.

The 15min-IC50 of aureomycin, polymyxin and Chloromycetin were 12.06, 6.24 and 429.90 mgL-1, the toxicity

descended in the order of polymyxin, aureomycin and Chloromycetin. The 15min-IC50 of ethanol, acetate,

propionate and butyrate were 19.40, 20.71, 10.47 and 12.17 gL-1 respectively, the toxicity descended in the order

of propionate, butyrate, ethanol and acetate.

The R values of anaerobic digestion intermediates (quad mixtures), intermediates together with polymyxin

(penta mixtures), intermediates together with Chloromycetin (penta mixtures) were 0.779, 1.684, 2.384

respectively, their joint effects were all additive. The R values of intermediates together with aureomycin (penta

mixtures),intermediates together with three antibiotics (hepta mixtures) were 3.005, 3.827 respectively, their joint

effect were synergistic.


Study on Conversion of the Mass and Energy and Microecological Characters inA+OSA Excess Sludge Reduction Process

By Li Jia

Chongqing University

At present, excess sludge produced by has been a restriction of development for municipal wastewater treatment

plants (WWTPs) in the world. The way to solve the problem from the root, is one of the urgent problems for the

environmentalists. And excess sludge reduction in-Situ, a important way to solve the problem of excess sludge, has

been gained great attentions. Our previous research showed that the A+OSA system, a modification of the

anoxic/oxic (A/O) process via insertion of a sludge holding tank into a sludge return line, has been demonstrated to

be capable of achieving simultaneous nutrient removal and sludge reduction. Also, the lower sludge yields of the

A+OSA system resulted from both the sludge holding tank and the main reaction units. In order to identify the

primary mechanisms involved, the research presented here was undertaken to: 1) the sludge characteristic and

microbial community structure in the two process; 2) the characteristics of cell synthesis under alternate

oxic/anoxic and its influence on the sludge reduction3) the physiological characteristics of the sludge in the two

process; 4) carbon and energy transport and transformation in the A+OSA technology. The main results are as

follows:

Compared to the reference system, the A+OSA system can reduce excess sludge by 13%~27%. Moreover, the

insertion of a sludge holding tank into the A/O process, had no obvious effect on the removal of nutrients. The

hydraulic retention time (HRT) is an important parameters which affected the sludge reduction, and the effect of

sludge reduction in whole system appeared an peak near the HRT 5.56h. The contribution factors to sludge

reduction differed under different HRT. When HRT is about less than 5.56h, the excess sludge reduction, resulted

from the lower yields of the main reaction units, but when HRT is more than 5.56h, the amount of sludge

compensative proliferation in the main reaction unit helped by the backflowed increasing organic loading offsets

the amount of sludge reduced by decay. Also, The longer the HRT in the sludge holding tank, the greater

contribution to the excess sludge reduction the sludge decay, the less contribution the bacterial of lower yields in

the sludge holding tank.

(.) The element analysis showed that the compozation are different between the two process, and thecompozation between the different reaction units also differed. Based on balances of carbon element, we found that

the content of carbon element was lowest. And this result showed the decayed in the sludge holding tank. The

sludge decayed increased sharply when the HRT prolonged. Compared with the reference, the carbon output in the

main reaction units of the A+OSA system was less, and the carbon used for organism synthesis was less either. But

the rate of cell synthesis in main reaction units of the A+OSA process was higher than it in the reference, while the

carbon output in gas form was just oppost. The energy balance indicated that the less energy was used to synthetize

organism in the A+OSA process. The loss of energy in form of power , heat, and spill in the reference was less than

it in the reduction process, but whether the energy spill or the energy uncoupling need further study.


Hydrogen Generation from Organic Wastewater in Microbial Electrolysis Cellsand Function Analysis of Anodophilic Communities

By Wenzong Liu


Nowadays, energy consumption and environmental pollution is a pair of paradoxical problems in the world. We

are confronted an increasing energy requirement and an inevitable environmental damage from fossil energy

utilization. An all-round solution is one of the important issues for the subject of environmental science and

engineering. New technologies are developing on waste water treatment and energy recovery. Microbial

electrolysis cells (MEC) have recently been developed as a new technology for organic wastewater treatment and

energy recovery. Exoelectrogenic bacteria are employed to effectively degrade wide organic substrates and produce

hydrogen by given a small external voltage.

Targeting at efficiency improvement of waste treatment and hydrogen conversion, this study was carried out as

follows: Reactor improvement and key factor analysis for higher hydrogen production; Dominant bacteria analysis

during reactor operating using single strand conformation polymorphism (SSCP); Methane production and methane

control to reduce hydrogen lose in single chamber MECs; Effects of different startup modes on MEC performances

based on functional gene analysis, and to find out the connections among reactor performances and community

structures; To elucidate microbial ecology questions in functional bacteria of MEC and explain the determination

of community structures to reactor performances.

(.)

After MEC reactors were updated to single chamber structure, COD removal and coulombic efficiency were

increased to 90% and hydrogen yield to 3 mole/mole acetate when applied voltage was higher than 0.5 V. Energy

efficiency came up to 180%. Targeting at methane production and damage to hydrogen loss in MEC, it was

possible to increase external voltage to control methane production. Results showed that methane could be

controlled below 4% when voltage enhanced to 0.6 V or more, but over 10% methane was got in gas production

when voltage was lower than 0.4 V in the experiment.

(.)

In the study, we tried to understand MEC process from community mechanism and inner regularity. Different

reactor performances were analysed in related to anodophilic community structures and it was tried to explain the

phenomenon of alternative stable states in the view of microbial ecology. It was found that community assembly

presented a stochastic process and formed various stable states in numbers of MEC reactors under the same

operations and conditions. Analysis indicated that reactor performance on energy gas production significantly

reflected community structures by canonical correlation analysis (CCA). Moreover, the results disclosed microbial

function structures determined reactor performance accordingly. These results were meaningful to build high

efficient functional communities and apply to practical waste water treatment in future.


Assessment Methodology and Regulation Pattern for Wastewater TreatmentProcesses Aimed at Energy Conservation and Emission Reduction

By Xu Wang

Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences

Wastewater treatment processes (WTPs) are facing challenges in terms of enhanced energy consumption, increased

waste production, and elevated greenhouse gas (GHG) emissions. However, current estimation schemes for WTPs

focus on treatment efficiency, effluent quality, and environmental consequences of WTPs for receiving water

bodies. These are factors that generally do not quantify the potential to convert wastewater pollutants into

recoverable resources. Therefore, the present work proposes a refined evaluation scheme that quantifies not only

adverse environmental effects, but also bioenergy and nutrient recovery indices. Subsequently, a novel regulation

pattern for pollutant transformation is proposed for facilitating energy conservation, emission reduction and

resource recovery in the WTPs.

The environmental profiles of six alternative WTPs are analyzed using life cycle assessment focused on

chemical use, energy consumption and GHG emissions. Effects of discharge standards on the environmental

impacts of WTPs are determined. Our findings reveal that the sophisticated wastewater treatment proposed for local

aquatic ecosystems can be realized at the cost of higher energy consumption, chemical use, and GHG emissions.

Thus, a multiple-target evaluation framework for WTPs is proposed, and the further estimate outcomes reveal that

the lower environmental sustainability of WTPs mentioned above can be offset by the resource recovery options

involved, even if increasingly stringent discharge standards are introduced.

Each estimate indicator in the proposed scheme has a specific significance, which may substantially affect the

final estimate results. Therefore, the definition of weighting set for each indicator is undertaken carefully, using a

global time series database. The data, collected from 52 countries between 1990 and 2010, are summarized and

analyzed. The outcomes reveal that the weighting coefficients have relative values, which vary by period and

country; weighted data of the indicators highlight the important factors during a certain period. Generally,

differences of weighted values for each indicator between developing and developed countries are remarkable, and

exhibit regularity. Next, forecasting models for the weighting coefficients are proposed on the basis of statistical

principles. According to the subsequent scenario prediction, phosphorus capture via struvite generation will be the

most sustainable option for developed countries, whereas nutrient recovery via sludge composting will be the better

choice for developing countries in the future.

The results also indicate that carbon substrates will affect energy consumption and resource recovery in

WTPs. Acetic acid is found to be dominated by substrate storage in a traditional activated sludge process, rather

than by total oxidization. This results in energy reduction in the water processing line, and facilitates phosphorus

gain in particular. Finally, the proposed regulation pattern for pollutant transformation could facilitate effluent

meeting Chinese Class 1A standards. Compared with the traditional pattern, 62.3% and 41.7% of energy

consumption and GHG emission, respectively, can be reduced with the proposed pattern. Moreover, with the new

regulation pattern, treating a cubic meter of wastewater can produce a net energy gain of 0.34 kWh.


Metagenomic insights into bio-functionality of 21 anaerobic biogas systems

By Yu Tao


Although abundant operational experiences has been accumulated to lead a well-functioned anaerobic digestion

(AD), the microbial reasons behind a robust/failing AD system and the community dynamics in response to

complex operational changes are still lack of insights. A balanced bacterial-archaeal community is undoubtedly a

key to successful AD. In this study, we comprehensively investigate bacterial and archaeal communities in 21 lab-

scale AD reactors using real-time qPCR and next generation sequencing. Our purpose is to link community

differences to reactor configurations, and eventually supply with some metagenomic insights into the bio-

functionality of AD reactors.

The working volume of all 21 reactors are in a range of 3.8 - 9.0 L. All reactors were inoculated with mature

sludge from pilot or full-scale AD reactors. Different substrates were fed to reactors, including enzymatically

hydrolysed brewers spent grain, pig manure, fine sieve fraction, brackish recirculation wastes and syntheticorganic medium. A total of 149 biomass samples were harvested for DNA extraction. A pair of new universal

primers (U515F and U1071R) were applied for 454 pyrosequencing (Roche 454 GS-FLX system). Another two

pairs primers, ARC787f ARC1059r; BAC516f BAC805r, were used for real-time qPCR of archaea andbacteria.

The universal primers for pyrosequencing cover most bacterial species (92.0%) and methanogens (95.2%). A

total of 652,975 sequences were retrieved for downstream analysis. Some key discoveries are:

Top seven phyla (Firmicutes, Bacteroidetes, Proteobacteria, Synergistetes, Chloroflexi, OP9 and

Euryarchaeota) account for 92.6% among total 50 phyla.

Bacteroides and Clostridium are most dominant genera (average abundance 28% and 14% of 149 samples) in

all reactors despite of different inocula and substrates, indicating AD reactors share similar

saccharolytic/fermenting members.

Organic substrate availability (in kg-COD/(kg-VSSd)) can impact both methanogen abundance and real quantity. Ahigh availability led to a high abundance and vice versa. This indicates that substrate availability determines the

ecological position of methanogens in AD reactors.

EGSB communities have the most diverse microbial diversity (calculated in Shannon index, Chao1, observed

species number and phylogenetic distance). EGSBs also have the highest methanogen abundance (Ave. 6.4%) and

amount (~ 1011 gene copies per gram dry biomass), which are about 10 times higher than the other reactors.

Accordingly, EGSB can bare the highest organic loading rate (Approx. 21 kg-COD/m3.d), which is 7-10 times higher

than the others.

It is intriguing to find that endospore-forming bacteria prevail in digester systems while biofilm-based reactors

are dominated by non-endospore-forming bacteria. This indicates different proliferous strategies in response to

various environmental stresses inside AD reactors.

By applying next generation sequencing and real-time qPCR on 149 samples out of 21 reactors, we captured some

prevalent phyla and genera who are dominant in almost every anaerobic biogas system. Meanwhile, it is critically

necessary to link AD systems functionality to its microbial community, both of which response to keyoperational/environmental factors such as organic loading (and its increasing rate), F/M ratio, salinity, temperature

and aggregation forms.


Increased production of hydrogen from glycerol by biokinetic control ofanaerobic sludge

PhD by Estela Tapia Venegas, Biochemical engineer, Master of science and PhD onBiotechnology, Pontificia Universidad Catlica de Valparaso, mail: [email protected]: Dr. Gonzalo Ruiz-Filippi. Escuela de Ingeniera Bioqumica, Pontificia Universidad Catlica deValparaso, Chile, mail: [email protected]

Glycerol from the production of biodiesel, is a promising alternative substrate for the production ofhydrogen by anaerobic digestion in the biorefinery context. The studies reported in literature show thatfacultative anaerobic microorganisms produce higher yields of hydrogen from glycerol. Therefore, thedevelopment of treatment with oxygen may isolate a larger quantity of facultative anaerobes and in turn removehydrogen-consuming microorganisms such as hydrogenotrophic methanogenic archaea which are strictlyanaerobic. The aim of this work was to develop a high yielding hydrogen production process using glycerol withan anaerobic sludge subjected to treatment with oxygen in a continuous system. To carry out the generalobjective were studied different inoculum treatment strategies; an un-pretreated sludge subject to a biokineticcontrol (TRH of 12 h), a sludge with glycerol acclimation, a sludge treated with heat shock (2 h, 105C) andother with oxygen treatment (24 h 8.2 ppm) in a continuous system (HRT 12 h) and the changes in microbialdiversity after each treatment were evaluated with the 16S rRNA gene and a functional gene for clostridialpopulations (hydA).

The best results in hydrogen production from glycerol were, acclimated sludge and sludge treated withoxygen, obtaining a yield of 0.35 molH2 mol-1glycerol and 0.46 molH2 molglycerol-1, respectively. The yieldsobtained were as high as reported in literature for anaerobic sludge from glycerol and also highlights that theprincipal metabolite produced was ethanol. Total microbial diversity (16S rRNA) and clostridial population(hydA) showed a dominance of clostridial populations, especially after the heat shock treatment unlike thecultivations submitted to treatment with oxygen, which may involve the participation of no clostriales(Enterobacteriaceae populations family) in hydrogen production.

In this doctoral thesis was developed a new treatment with oxygen that increased the hydrogen yield of ananaerobic sludge in a continuous system from glycerol. Hydrogen production with this treatment (in regards toobtained ethanol yields, as in the functional gene of the Clostridium gender analysis) would be associated toclostridial and non clostridial communities (generally microorganisms from the Enterobacteriaceae family).


Startup and Stability of Thermophilic Anaerobic Digesters Treating OrganicWaste in the Absence of an Acclimated Seed.Sophia Abboud Ghanimeh for Doctor of Philosophy

Department of Civil and Environmental Engineering, Notre Dame University, Lebanon

Successful startup and durable stability are key determinants for dissemination and longevity of thermophilicanaerobic digesters treating the source-sorted organic fraction of municipal solid waste (SS-OFMSW). However,startup is often long and problematic because of lack of acclimated inocula, and system stability is challenged byoperational disturbances, such as organic shock loading. In this context, the present work attempts to improvestartup and system stability by investigating the impact of mixing and addition of hydrogenotroph-rich seeds,namely compost and leachate.

In this context, continuous slow stirring induced a stable startup by reducing the average VFA accumulationfrom 2,890 mg HAc/l to 825 mg HAc/l, propionate content from 2073 mg/l to 488 mg/l, and VFA-to-alkalinityratio from 0.32 to 0.07. As a result, the startup with slow mixing was faster and smoother accomplishing ahigher loading capacity of 2.5 gVS/l/d in comparison to 1.9 gVS/l/d for non-mixing. Mixing equally improvedmicrobial abundance from 6.6 gVSS/l to 10 gVSS/l and enhanced solids and soluble COD removal.

In addition, mixing reduced the formation of micro-environments; thus, eliminating the occurrence of nicheswith high concentrations of inhibiting metabolic intermediates/wastes. As a result, the Archaea in the mixeddigester were dominated by hydrogenotrophic Methanobateriaceae (61%), with 35% acetoclasticMethanosarcinales, and most of the methane was produced via syntrophic pathways. In contrast, Archeaea in thenon-mixed digester were predominated by Halobacteria (65%), resulting in higher acids levels and lowerallowable loading rate. Accordingly, mixing was found beneficial in dissipating potential inhibitors and inimproving stability and loading capacity, particularly when a non-aclimated seed, often lacking balancedthermophilic microflora, is used.

On the other hand, the addition of compost and leachate induced a surge in the number of hydrogenotrophic(3 times) and acetotrophic (1000 times) methanogens in the initial seed mix. However, this impact wasattenuated with time, resulting in 35% increase in acetotrophs and 31% reduction in hydrogenotrophs at steady-state. During the startup phase, the addition of compost and leachate induced a faster acclimation of themicrobial flora with lower soluble COD and intermediate-to-partial alkalinity ratio, implying better degradationof soluble compounds and improved stability. At steady state, the system with added compost and leachateexhibited lower propionate levels, resulting in lower VFA concentrations and increased buffering capacity. Thelatter is necessary to (1) resist progressive shocks due to incremental loading during startup, and (2) withstandpotential disturbances during steady-state operation

Furthermore, the addition of compost and leachate to the initial seed improved the systems resistance andresilience under a sustained organic shock-load (equal to double the regular load). While the control digesterfailed after shock loading, the digester with added compost and leachate was able to restore its functionality with90% recovery of pre-shock methane generation rate at stable pH in ~3 months.


Interspecies Electron Transfer in environmental and engineered syntrophicsystems

Marie Stephanie Natacha Juste-Poinapen for Doctor of Philosophy

Advanced Wat

iwa anaerobic digestion sg newsletter_2014-09

Documents