Anaerobic Processes

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<p>FACULTY OF COMPUTING, ENGINEERING and SCIENCEFinal mark awarded:_____</p> <p>Assessment Cover Sheet and Feedback Form 2014/15</p> <p>Module Code:RE4S008Module Title:Anaerobic Treatment ProcessesModule Lecturer:Dr. Iain Michie</p> <p>Assessment Title and Tasks: Mini project and poster presentationAssessment No. 3e.g. 1 of 3</p> <p>No. of pages submitted in total including this page: Completed by studentWord Count of submission(if applicable): Completed by student</p> <p>Date Set:9/10/2014Submission Date: 26/03/2015Return Date:23/04/2015</p> <p>Part A: Record of Submission (to be completed by Student)</p> <p>Extenuating CircumstancesIf there are any exceptional circumstances that may have affected your ability to undertake or submit this assignment, make sure you contact the Advice Centre on your campus prior to your submission deadline.</p> <p>Fit to sit policy: The University operates a fit to sit policy whereby you, in submitting or presenting yourself for an assessment, are declaring that you are fit to sit the assessment. You cannot subsequently claim that your performance in this assessment was affected by extenuating factors. </p> <p>Plagiarism and Unfair Practice Declaration: By submitting this assessment, you declare that it is your own work and that the sources of information and material you have used (including the internet) have been fully identified and properly acknowledged as required[footnoteRef:1]. Additionally, the work presented has not been submitted for any other assessment. You also understand that the Faculty reserves the right to investigate allegations of plagiarism or unfair practice which, if proven, could result in a fail in this assessment and may affect your progress. [1: University Academic Integrity Regulations] </p> <p>Details of Submission: Note that all work handed in after the submission date and within 5 working days will be capped at 40%[footnoteRef:2]. No marks will be awarded if the assessment is submitted after the late submission date unless extenuating circumstances are applied for and accepted (Advice Centre to be consulted). [2: Information on exclusions to this rule is available from Campus Advice Shops] </p> <p>Work should be submitted as detailed in your student handbook. You are responsible for checking the method of submission.</p> <p>You are required to acknowledge that you have read the above statements by writing your student number (s) in the box:</p> <p>Student Number(s):</p> <p>IT IS YOUR RESPONSIBILITY TO KEEP A RECORD OF ALL WORK SUBMITTED</p> <p>Part B: Marking and Assessment(to be completed by Module Lecturer)</p> <p>This assignment will be marked out of 100%</p> <p>This assignment contributes to 50% of the total module marks.</p> <p>This assignment is non- bonded. Details :</p> <p>Assignment Title and Tasks: : Individual Mini-Project and Presentation Challenges in the implementation of integrated anaerobic processes for waste treatment</p> <p>Format for the report1. Summary2. Introduction to the anaerobic treatment processesa. Critically review present status of technical development b. Field applications (if existent): characteristics and status c. Literature related to environmental and economic benefits of each process3. Selection of one main combination for the integration of these processes for waste and wastewater treatment and bioenergy recoverya. Present a case for the integration and the respective system flow diagramb. Evaluate the potential for the integrated process related to technical, economic and environmental performancesc. Evaluate the challenges that may occur in delivering such integrated anaerobic treatment systemd. Discuss possible improvements for the integrated anaerobic treatment systeme. Discuss the needs to integrate with other complimentary processes in order to maximise efficiencies and quality outputs 4. Conclusions5. References</p> <p>Important note: If biogas is produced from your selected process, it is compulsory to include biogas upgrading as a technique for biomethane production for gas grid injection or for transport fuel.</p> <p>It is anticipated that in addition to the materials provided in the lectures, you will be required to research much more widely available literature. Reviewing a number of journal publications is certainly be a requirement.</p> <p>The report should not have more than 4500 words (and accounts for 30% of the mark). Please submit the report on the 26th March 2015. You will also be required to do a presentation for 20 mins using a powerpoint slide with the main information that you have included in your report. Questions from the lecturers assessing the presentation will follow at the end of your presentation. The presentation will take place on 26th March 2015 during the normal scheduled class and accounts for 20% of the mark.</p> <p>This individual mini project report and poster presentation contributes 50% to the overall mark for this module.</p> <p>ContactPlease contact Dr. Iain Michie if you need further assistance and advice related to this individual mini projectEmail: </p> <p>Learning Outcomes to be assessed (as specified in the validated module descriptor This assignment addresses the following learning outcome(s) of the module:</p> <p>1. Demonstrate a sound knowledge of scientific and technical principles of the anaerobic treatment processes 2. Critically review the factors that influence process selection, reactor design and operation for each anaerobic treatment process 3. Ability to specify and conduct an effective process monitoring regime 4. Evaluate the needs to integrate an anaerobic treatment process with other complimentary ones in order to maximise efficiencies and quality outputs 5. Critically evaluate the environmental and economic benefits and impacts of utilising each anaerobic treatment process in terms of treatment efficiency, energy savings or net bioenergy yield as well as production of other products from process intermediates or from digestate </p> <p>Grading Criteria:Marks AvailableMarks Awarded</p> <p>Report:</p> <p>1. Quality of summary and conclusions15</p> <p>2. Structure and presentation of the report15</p> <p>2. Quality of referencing10</p> <p>4. Critically review individual process technologies (applications, status, benefits and challenges)30</p> <p>5. Evaluation of the system integration30</p> <p>Poster presentation:</p> <p>1. Quality of the structure and presentation of the poster25</p> <p>2. Relevance of contents of the poster25</p> <p>3. Clarity in the presentation and ability of convey the message within thetime allocated25</p> <p>4. Ability to answer questions25</p> <p>Feedback/feed-forward (linked to assessment criteria): Areas where you have done well:</p> <p> Feedback from this assessment to help you to improve future assessments:</p> <p> Other comments</p> <p>Mark:</p> <p>Markers Signature:</p> <p>Date:</p> <p> Work on this module has been marked, double marked/moderated in line with USW procedures.</p> <p>Provisional mark only: subject to change and/or confirmation by the Assessment Board</p> <p>Part C: Reflections on Assessment(to be completed by student optional)</p> <p>Use of previous feedback:</p> <p>In this assessment, I have taken/took note of the following points in feedback on previous work:</p> <p>Please indicate which of the following you feel/felt applies/applied to your submitted work A reasonable attempt. I could have developed some of the</p> <p>sections further. A good attempt, displaying my understanding and learning, with </p> <p>analysis in some parts. A very good attempt. The work demonstrates my clear </p> <p>understanding of the learning supported by relevant literature and scholarly work with good analysis and evaluation. An excellent attempt, with clear application of literature and</p> <p>scholarly work, demonstrating significant analysis and evaluation. </p> <p>What I found most difficult about this assessment:</p> <p>The areas where I would value/would have valued feedback:</p> <p>Challenges in the implementation of integrated anaerobic processes for waste treatment</p> <p>Radu Ivanescu (14089637)Anaerobic treatment processRenewable energy and Resource management</p> <p>Table of content</p> <p>1. Summary2. Introduction to the anaerobic treatment processesa. Critically review present status of technical development b. Field applications: characteristics and status c. Environmental and economic benefits of each process3. Integration of the previous processes for waste and wastewater treatment and bioenergy recoverya. Integration and the respective system flow diagramb. Evaluation of the potential integrated process related to technical, economic and environmental performancesc. Evaluation of the challenges that may occur in delivering such integrated anaerobic treatment systemd. Discussion on possible improvements for the integrated anaerobic treatment systeme. Discussion of the needs to integrate with other complimentary processes in order to maximise efficiencies and quality outputs 4. Conclusions5. References4. Conclusions5. References</p> <p>1. Summary</p> <p>The following report focuses on the waste treatment of a dairy farm taking in consideration current technical development and future anaerobic trend technology. Mainstream anaerobic treatment processes are based on the conversion of organic matter in the absence of oxygen, by microorganisms, into biogas. This kind of process is energy-efficient and is mainly used to treat warm industrial wastewaters with a high concentration of biodegradable organic matter (measured as BOD, COD and/or TSS). Anaerobic biological decomposition of waste use substantially less energy, require a low amount of chemicals and have low sludge handling costs compared to other aerobic treatment processes. Also, the biogas resulted from the process is a renewable source of energy that can be a good replacement for natural gas or can be used to generate electricity.</p> <p>2. Introduction to the anaerobic treatment processes</p> <p>a. Critically review present status of technical development </p> <p>For the following report a dairy farm was taken in consideration. The actual development of the waste treatment consists of an Anaerobic Digester where the feedstock is treated. The reactor type is ADI-BVF Anaerobic Reactor [1]. Due to its low-rate anaerobic process and the high hydraulic retention time the system provides stability and efficiency of the process. The waste of the sludge is thus minimized and can be used as landfill once or twice per year.</p> <p>The design of the reactor enables the biological solids to settle into the sludge bed. The reactor also contains a gas-liquid-solid separator that produce a low effluent TSS. The current configuration of the reactor is Type L, a partially in-ground concrete earthen basin. Waste pre-treatment is not required as the reactor has a coarse screening and a wide operating temperature rate (20-400C).</p> <p>The feedstock is inserted beneath the sludge bed via an influent distribution system. An adjustable pumping schedule dictates the way that the feed mixes with the recycled sludge, thus, by the uprising of the wastewater through the sludge bed results an enhanced contact between the two of them. Thereby under the microbial decomposition of the biomass, BOD, COD, TSS and FOG are converted into biogas.</p> <p>The biogas is collected by a membrane system after it rises through the liquid. The collected gas is extracted with the help of the negative pressure created by external blowers, stopping the escape of the gas or odours in the environment. The membrane system collects and stores the biogas, minimizes heat loss and has the potential for rainwater collection. The membrane has a higher resistance to corrosion than concrete or steel, is UV resistant and provides easy maintenance without the need of pausing the process.</p> <p>The biogas, currently is used to power a CHP system in order to generate electricity for the blowers used at the digester and also to provide heat for the digester. The waste sludge that results from the reactor goes into a separator. Here, after presses are used, the solid content is used for animal bedding or for soil amendment or peat moss replacing. The remaining liquid is decanted in a lagoon. The actual configuration of the waste treatment facility is shown in Figure 1.</p> <p>Figure 1. Current configuration of dairy waste treatment</p> <p>b. Field applications: characteristics and status </p> <p>Additional technologies can be employed in order to make the feedstock treatment more effective. Besides the currently used processes that offer animal bedding and soil amendment as final products, other benefits can arise from using a gas scrubber, basins for nutrient recovery and a pyrolysis system.</p> <p>GAS SCRUBBER</p> <p>A cost-effective method of upgrading the biogas could provide dairy farmers the means to complement or replace the electrical power used from the grid. Also, because of the similar proprieties between biogas and natural gas, biogas driven cars and buses can refuel from it.</p> <p>The methods that can be used for gas scrubbing and are commercial available are as follows:</p> <p> Water and Polyethylene Glycol Scrubbing process used to remove CO2 and H2S from biogas. The process is purely physical as CO2 and H2S are more soluble than methane. The flow chart for this technology is presented in Figure 2.</p> <p>Figure 2. Flow chart of Water and Polyethylene Glycol scrubbing process</p> <p> Chemical Absorption this process needs a relatively high energy input in order to break the bonds created between the solute and the solvent in order to regenerate the solvent. The H2S is completely removed from the biogas using this technique. A flow chart of the process is represented in Figure 3.</p> <p>Figure 3. Flow chart of chemical absorption process.</p> <p> Pressure swing adsorption with the use of different adsorbent materials, a specific gas can be separated from a mixture of gases. The process takes place by changing the pressure of the gas mix, first high pressure in order to have an adsorption of the desired gas, then low pressure to desorb the adsorbent material.(Cavenati et al., 2005) [2]. The flow chart diagram is represented in Figure 4.</p> <p>Figure 4. Flow chart of Pressure-swing adsorption</p> <p> Membrane separation a thin membrane allows some components of the raw gas to pass while others are retained. Typical operating pressures are between 25-40 bars. The purity of the methane yield can be enhanced by adding more membrane modules, but a drawback will be felt in the quantity of methane produced. The flow chart in Figure 5 represents the membrane purification process.</p> <p>Figure 5. Flow chart of membrane biogas purification process.</p> <p> Cryogenic separation this process is based on the fact that CO2, H2S and all of the other components can be separated from the CH4 because of different liquefaction point. The process takes place at low temperature (-100oC) and high pressures (40 bars). The schematics of the cryogenic separation is represented in Figure 6.</p> <p>Figure 6. Schematic of cryogenic separation</p> <p>PYROLYSIS</p> <p>Pyrolysis is a...</p>