PROJECT FINAL REPORT

Grant Agreement no.: 212180

Project acronym: SUPER METHANOL

Project title: Reforming of Crude Glycerine in Supercritical Water to ProduceMethanol for Re-Use in Biodiesel Plants

Funding Scheme: Collaborative Project

Project period: 1 January 2008 - 31 December 2011

Coordinator: BTG Biomass Technology Group BV (The Netherlands)

Project website: www.supermethanol.eu

Content:

I. Executive summary

II. Summary description of project context and objectives

III. Description of the main S&T results/foregrounds

IV. Potential impact

V. Website and contact details of project partners

I. Executive summary

The SuperMethanol project involved RTD in the following areas: (a) Production of syngas from glycerine byreforming in supercritical water; (b) Syngas conversion into methanol at high pressures; (c) Production ofmethanol from glycerine feedstock; (d) Process modelling; (e) Economic assessment and basic engineering ofa full-scale glycerine-to-methanol demo plant.

Reforming of crude glycerol and gas upgrading: In two continuous set-ups glycerol (pure and crude) wasreformed in supercritical water. The influence of the process conditions, feed concentration, and presence ofalkali on the conversion and gas yields was investigated. Clear trends in gas yields were observed as afunction of the carbon-to-gas efficiency. Overall, the carbon fed as glycerol ends up in carbon oxides andhydrocarbons with a product ratio of roughly COx:CyHz = 2:1. The ratios of CO:CO2:H2 can be steered by theoperating conditions. The influence of a range of catalysts on the upgrading of the syngas, to optimise it formethanol synthesis, was determined, together with theoretical and experimental analysis of the recycling oftail water and CO2.

Synthesis and end-uses of SuperMethanol: Using artificial gas and a commercial catalyst, methanol wassynthesised at high pressure (HP) and various temperatures. At high pressure and relatively low temperaturemethanol condensation was visually observed. This phenomenon promotes methanol synthesis enabling muchhigher conversions. Simultaneous chemical and phase equilibria were modelled. Complete conversion of thelimiting component was obtained, meeting the research target of 90% syngas conversion. Relations betweenoperating temperature, gas composition, and products were established. Biodiesel was successfully producedfrom SuperMethanol samples. Work was dedicated to understand and predict the phenomenon of liquidmethanol formation.

Process modelling: The available thermodynamic data in the literature were reviewed and completed with theresults obtained during the experimental research described above. Data were used to model the entireglycerol-to-methanol (GtM) process. Aspen Plus software using the Soave-Redlich-Kwong and Peng-Robinson equations of state was used for process simulation. The results indicate that methanol synthesis isfavoured by increasing pressure. The effect of syngas inlet temperature and inlet-stream pressure on processoutput was analysed. A flowchart of the entire process was made including mass and energy balances.

Pilot plant design, setting up and experimental testing: The GtM process was demonstrated in anintegrated process development unit (PDU), combining a small-scale test rig for reforming and a set-up for HPmethanol synthesis. Among the successes achieved was a series of continuous runs demonstrating the fullfunctionality of the system. Initially, due to the unfavourable composition of the gas derived from glycerol andthe incomplete conversion of glycerol the overall conversion of carbon in glycerol to carbon in methanol wasexpectedly low (10 %), but after minor modifications a final carbon conversion of 62 % (equal to 0.65 kgmethanol/kg glycerol) was achieved in a run of over 30 h.

Design of a demonstration unit: A major outcome of the project was the preparation of a blueprint (designpackage) for a full-scale GtM demo unit to be installed at and integrated with the biodiesel production plant ofACCIONA in Caparroso (Navarra, Spain), In a market study glycerine and methanol markets were analysed.The study provided data on glycerine availability and prices, its current uses, the R&D work being carried outand the actors important in this area. The economic feasibility of the proposed demo unit was determined.Under the market conditions experienced in recent years the installation of the GtM unit is not economicallyviable due to high investment costs leading to high specific production costs.

II. Summary description of project context and objectives

Ideas behind the projectBiodiesel is produced by trans-esterification of vegetable oils with methanol. Glycerine is a major co-productof this process and due to the rapid increase in biodiesel production in Europe since 2003 the amount of(crude) glycerine on the market has grown substantially. In 2004 the amount of glycerine produced exceededthe actual consumption, and the mismatch increasing in the years after resulting in an ever lower glycerineprice. In late 2006 the price was not much higher than its value as fuel. With the flattening of the growth inbiodiesel production, glycerine prices have recovered in recent years. Nevertheless, leading stakeholders in theEU biodiesel sector have confirmed that there remains a need to identify new applications to valorise (crude)glycerine. An interesting option is that the biodiesel plant produces methanol from its crude glycerine; theproducers will then be less dependent on the methanol spot price, as there is a (perhaps partial) security ofsupply of methanol, and their own co-product is turned into a green(er) feedstock. The SuperMethanol projectfocused at the development of an innovative glycerine-to-methanol process that could be operatedeconomically by biodiesel producers to convert 3,000 - 10,000 t glycerine per year into methanol.

The project expands on expertise of the project partners on the reforming of biomass in supercritical water,using a variety of feedstocks including glycerine. An initial scoping study, done in 2006, showed thatsupercritical reforming of (crude) glycerine integrated with methanol synthesis, also referred to as the GtM(Glycerine-to-Methanol) concept, can be promising. A simplified diagram of the proposed system integratedin a biodiesel plant is shown in Figure 1. With the GtM concept more than 60 wt% of the glycerine can beconverted into methanol, and some combustible gases can be used to generate process heat or electricity. Inthe GtM concept water and glycerol are required as a feed, while the ash in the crude glycerine and CO2 leavethe process.

Figure 0.1 Simplified diagram of the biodiesel production unit coupled with the GtM process

The integration of glycerine reforming and methanol synthesis in the GtM process has severaldistinct advantages:o Glycerine can be reformed to syngas with syngas composition steered by the process conditions;o The water used in the process will extract the contaminants from the gas and additional gas cleaning is not

required;o The water can be recycled in the reforming process minimising the use of resources;

o The syngas becomes available at high pressure (up to 250 bar), enabling once-through methanolsynthesis. There is no need for any recycling of gas, eliminating high gas compression costs;

o The quality of the methanol (and some higher alcohols) is good enough for use in the biodieselproduction. Expensive methanol purification may be limited or absent.

Figure 0.2 shows a process description for the GtM process.

Figure 0.2. The GtM concept: from (Crude) Glycerine to Methanol.RSCW = reforming in water at supercritical conditions.

ObjectivesThe key objectives of the SuperMethanol project are to obtain and then further improve the energy balance,carbon performance, the sustainability and the overall economics for biodiesel production, and to reduce thesensitivity of biodiesel plant economics to volatile methanol and glycerine prices.

To reach these objectives, the following secondary objectives were to be realised:1. The development of the GtM process on laboratory and pilot plant scale to demonstrate (crude) glycerine

conversions > 90% and to produce a syngas with H2/CO > 1, CO2 < 20 vol.%, (CH4+C2+) concentration <

10%, and subsequent conversion to methanol yielding over 90% on syngas. The target is to obtain anoverall yield of 50% methanol from (crude) glycerine;

2. Preparation of a blueprint for a full-scale methanol production facility integrated in a biodiesel productionplant, and establish production costs for the super methanol. The target is to produce methanol at a pricebelow € 250 per tonne (price 2007).

Relevant core processes of the whole GtM chain that need to be researched include:a) Production of syngas from glycerine by reforming in supercritical waterb) Syngas conversion into methanol at high pressuresc) Production of methanol from glycerine feedstock

Key research indicators of technical progress establishing the GtM process that will be monitoredcontinuously during project implementation of the process as presented in the project proposal include:

Performance / research indicator Target BaselineGas yield: RSW = Masstotal gas produced /Massfeed,in RSW > 90% RSW < 65 %Stoichiometric number – SN = (H2-CO2)/(CO+CO2 SN>1 SN ~ 0.5Remaining concentration hydrocarbons: HC = (CH4+C2

+)out HC < 10% HC ~ 20%Methanol yield: CH3OH=MassCH3OH+,out/Mass (H2+CO+CO2),in CH3OH>90% CH3OH < 60%

(low pressure)

Baseline and target values for each of these indicators are monitored during the project (see Figure 0.3):

Figure 0.3: Schematic representation of anticipated technical progress.

Overall strategy and work planInitially, the two core processes of the GtM chain (the reforming process and the methanol synthesis process)were analysed, developed and demonstrated on lab scale. Main research issues related to the reforming ofglycerine in supercritical water included:

o The dependence of the raw syngas composition versus operating parameters: A dedicated study on thereforming of (crude) glycerine is carried out, focussing on longer term effects (especially build up ofcontaminants), and recycling of tail water;

o The raw syngas is rich in CO2: experiments, supported by thermodynamic calculations, are to be carriedout to reduce the CO2 concentration, within the reforming process itself or in subsequent conditioningsteps, or, as was discovered later in the project, to use the CO2 as a feed for methanol synthesis;

o The reduction of (remaining) hydrocarbons (e.g. CH4 and C2+) in syngas as this significantly affects the

subsequent methanol synthesis in terms of syngas composition, yields, and efficiencies. The use ofcatalysts was extensively studied as well to reduce hydrocarbon concentrations

Main research items related to methanol synthesis included:

o Establishing the effects of such higher pressures using state-of-the-art but also newly developed catalystsfor methanol synthesis, its effects on the quality of the methanol produced and its by-products.

o Research on the methanol quality versus its suitability for trans-esterification to produce biodiesel.o The effect(s) of CO2 on methanol synthesis.o Analysing the purity of the methanol as produced under the more extreme conditions related to the

required purity for biodiesel production.

The two core processes are successfully integrated into a small pilot plant set-up. Extensive experimentationwas done in the pilot plant set-up to generate the data needed on the complete chain for the design of a demounit. Initially yields of glycerine to methanol over 54% were foreseen, based on the calculation carried out in2007, prior to starting the research. However, yields over 60% were obtained in modified systems. A design ofa full-scale GtM demo unit (on commercial scale) has been prepared on basis of information provided bythese experiments.

III. Description of the main S&T results/foregrounds

WP1: Reforming of crude glycerine and gas upgrading

IntroductionFor the conversion of glycerol into methanol glycerol needs to be reformed to produce a syngas. The syngascomposition is strongly related to the process conditions and the presence of a catalyst. The main reaction inglycerol reforming is:

C3H8O3 + a H2O CO + H2 + CO2 + H2O + CH4 + Cx’Hy’Oz’ (eq. 1.1)

By-products (Cx’Hy’Oz’) are low molecular weight organic compounds, polymerised products, higherhydrocarbons (x’≥2, z’=0), or elemental carbon (y’=z’=0). Some of the low molecular weight organics can react further to gas phase components. Subsequent reactions of the gas phase components may also occur. Thefollowing gas phase reactions may occur, depending on process conditions:

CO + H2O CO2 + H2 (water-gas shift reaction) (eq. 1.2)

CO + 3H2 CH4 + H2O (CO methanation) (eq. 1.3)

CO2 + 4H2 CH4 + 2 H2O (CO2 methanation) (eq. 1.4)

TargetsThe aim of this WP was to gain insight in the gas yields obtained from glycerine, the glycerol conversion,process reliability, and the optimal operating window. A specific task is to determine the effect of theoperating conditions (temperature/pressure) on the gas composition. Depending on e.g. gas compositions andyields, conditioning or upgrading of glycerol may be further investigated. Aspects such as the recycling of tailwater and CO2 recycling will also be dealt with. Dozens of catalysts would be screened, of which several weretested more extensively in the pilot plant (see WP4).

Task WP1.1 Supply of crude glycerine (Acciona, SPQL)Acciona supplied both crude and pure glycerine for testing, as needed. The main impurity relevant forreforming appears to be salt (NaCl).

Task WP 1.2 Reforming of crude glycerine (BTG, Maribor, Acciona, SPQL)Before starting the experimental programme thermodynamic calculations were performed. Equilibriumcompositions for glycerol reforming were calculated, wherein higher hydrocarbons are neglected. Equilibriumyields in case of considering methanation and water-gas shift strongly depend on temperature and feedconcentration. In case of only the water-gas shift, gas compositions are nearly independent of the temperatureand feedstock concentration (which corresponds to experimental data).

Reforming of methanol (with Na2CO3), glycerol, and crude glycerol in supercritical water (SCW) wasexperimentally investigated to gain insight in the overall mechanism of such reactions. Experiments weredone in two continuously operated set-ups, here referred to as ‘lab scale unit’ (Figure 1.1, 1 L/h feed) and‘pilot plant’ (up to 10 L/h feed, not depicted here).

The feed for the pilot plant (also referred to as process design unit, PDU) can be heat-exchanged with thereactor effluent in a counter current heat exchanger. The reactor was placed in a furnace and heated byburning propane or natural gas. The glycerol reforming experiments were carried out at temperatures between460-650ºC, feed concentrations of 5-20 wt%, and residence times of 6-43 s. Pressure was maintained at 255-270 bar.

Figure 1.1 Schematic flow sheet of the continuous lab-unit. Gas-liquid separation after pressure reduction(A). In situ gas-liquid separation (B).

Figure 1.2 Gas composition as function of the CGE for the different components. Experimental conditions: T =460 – 650 ºC, [feed] = 5 – 20 wt%, = 6 – 173 s. RME refers to crude glycerine.

The carbon-to gas efficiency (CGE) for glycerol and crude glycerine increases with temperature, reaching over90% for both feeds at a reactor temperature of around 600 ºC. The presence of alkali in the feed enhances theCGE at low temperatures, but the effect is hardly visible at higher temperatures. In the experiment with a feedconcentration of 15 wt% crude glycerine, salt deposition and loss of active wall surface area were observed.The gas composition appeared to be a function of the conversion within the conditions investigated (seeFigure 1.2). H2, CO, and CO2 increase as a function of the conversion for both types of glycerol and start todeviate at CGE > 50 %, mainly caused by the increased rate of the water-gas shift reaction due to the presenceof alkali.

Over the complete conversion range, the CO yield increases for pure glycerol, however, there is a maximumaround CGE = 60 % for crude glycerine. Comparing with the equilibrium calculations, the gas yield for pureglycerol remains far from equilibrium, while it approaches equilibrium at CGE > 80 % for crude glycerine.Pure and crude glycerine yield up to 0.6 mole CH4/mole feed. CH4 is a primary gas product and is producedinstantly. Overall, at CGE = 100 %, 2 of the 3 carbon molecules originally present in the glycerol becomeeither CO or CO2, while the other carbon molecule ended up as a hydrocarbon.

Task 1.3 Catalyst preparation/testing for the upgrading of RSCW gas (BIC, Maribor, BTG)Several catalysts were prepared and tested in methanol and glycerol reforming to research if the hydrocarboncontent of the gas can be reduced. The explorative screening study for glycerol was conducted for catalystsnamed SMC-1 to SMC-5 and PK-80. All catalysts significantly promote the conversion at low temperatures.At 690oC the conversion of glycerol without catalyst was near 40 %, while in the presence of catalysts(almost) complete conversion could be obtained. All catalysts promote the water-gas shift reaction, while theones based on Ni also affect the methanation. For three catalysts coke formation was very limited ornegligible. The specific surface area of all catalysts decreased except for PK-80. XRD analysis indicate onlyminor changes in crystal structure of the supports. In Table 1.1 a qualitative comparison of the catalysts isgiven.

Table 1.1 Qualitative summary of the functionality of the catalysts in glycerol reformingCatalyst C-C scission Methanation WGS Reforming of

C2/C3Coke

formation

SMC-1 +++ +++ +++ +++ +/-

SMC-2 +/++ - +++ - +++

SMC-3* ++ ++ +++ +++ +++

SMC-5 +++ ++/+++ +++ +++ -

PK-80 + +/- +/- - +/-

- No influence; * Smallest amount of catalyst; + = little promotion; ++ = moderate promotion+++ = strong promotion

The gas compositions obtained with the different catalysts were initially considered as not being attractive formethanol synthesis. However, as insights in methanol production increased (WP2), and it appeared possibly tohydrogenate CO2, especially catalysts SMC-1 showed to be a very interesting catalyst.

A list of catalysts investigated for gas upgrading after the reforming step is given in Table 1.2. A premixedmodel gas was led over a catalyst bed at several pressures and temperatures. At the higher temperatures(T>400oC) an increase of CH4 and CO2 concentrations accompanied with decreasing H2 and COconcentrations was observed. Overall, none of these catalysts is shown effective in decreasing the CH4 contentin the temperature and pressure interval of RSCW.

Table 1.2 Catalysts for gas upgrading

Catalyst code Particle size (mm) Target reactionCDC-1 (CAM) 0,5-1 CO2 reductionCDC-2 (CP) 0,5-1 CO2 reductionCDC-3 (IMP) 0,5-1 CO2 reduction

Task 1.5 Tail water and/or CO2 recycle (Sparqle, Maribor)Gas from RSCW consist of H2, CO2, CO, CH4 and minor quantities of C2/3 hydrocarbons. The gases formedare at high pressure, which allows in-situ treatment, for example to separate the CO2. The CO2-poor synthesisgas is fed to the methanol reactor and CO2 is exported. Later on in the project the removal of CO2 appeared tobe superfluous. Desktop studies for the removal of CO2 showed that reforming of crude glycerol can reach acalculated thermal yield of 93%. Options have been investigated using methanol, water or amines as CO2

extraction agents. Recycling of tail water to the reformer shows additional advantages as it prevents disposal

of waste water, it prevents loss of reformer gas as there is no expansion of tail water to atmospheric pressure,and it utilises the resource potential of glycerine to its maximum. Further insight in the methanol synthesis,however, also showed that (i) next to the hydrocarbons, CO2 is an important cause of the decrease in theoverall GtM (glycerol-to-methanol) carbon yield, but (ii) at these high pressures the largest part of CO2

(usually >70%) can be converted to methanol as well, in relatively high reaction rates. Tests have been carriedout where tail water is recycled back to the reformer in both systems, single reforming mode as well as in theintegrated reformer - methanol synthesis system. The recycling of tail gas is schematically shown in Figure1.3 below. Glycerol is injected in the recycle stream, but may in an optimised design be injected in the reactor.

Figure 1.3 Schematic flow sheet of the set-up including the recycling of tail water.

Though difficult as not sufficient data is available at exactly the same conditions, comparing the gascomposition from the recycle mode with the once-through mode shows that recycling does not influence theoverall gas composition significantly. CO2 has no effect on the reformer performance in terms of derived gascomposition, although a slight reduction in the hydrocarbons may be visible. Typical results are shown inTable 1.3. Experiment 1 is an experiment without recycling, and gases refer to the gas composition in the highpressure separator (HPS) and low pressure separator (LPS) respectively. It can be compared to experiment 2,where recycling is taken into account at a slightly lower temperature, and effectively similar CO and lowerCO2 are measured. In experiment 4 the feed concentration is higher than the other experiments, but the gascomposition is similar to the gas composition in experiment 3. The hydrocarbon concentrations, however,seem to be slightly lower. Interestingly, using recycling of water (with CO2) allows the CO2 to be used formethanol synthesis.

Table 1.3 Comparison of experiments with and without effluent water recycleOverall gas composition Gas composition of HPS and LPS

Exp. Feed H2 CO CO2 CH4 C2H6 v Cbal v H2 CO CO2 CH4 C2H6

wt% vol% vol% vol% vol% vol% L/h % L/h vol% vol% vol% vol% vol%

1 10.4 41.5 19.6 22.1 11.2 5.6 121 96 HPS 106 44.3 21.2 16.5 12.1 6.0

LPS 15 21.9 8.4 62.0 5.5 2.2

2 8.2 41.7 25.9 17.2 10.9 4.2 109 99

3 9.0 50.2 1.4 33.7 10.2 4.5 143 98 HPS 126 54.8 1.6 27.5 11.2 5.0

LPS 16 14.3 0.2 82.1 2.6 0.8

4 19.5 54.9 3.7 30.1 8.6 2.8 341 92

ConclusionGlycerol (pure and crude) was reformed in supercritical water, in two different continuous set-ups. Theinfluence of the process conditions, feed concentration, and alkali on the conversion and gas yields wasinvestigated. Methanol was used as a model component to provide insights in the reforming in supercriticalwater (RSCW) as well. Clear trends in gas yields were observed as a function of the carbon-to-gas efficiency.The carbon-to-gas efficiency increases with temperature and residence time, while increasing feedconcentration seems to have an slight adverse effect on the carbon-to-gas efficiency in case of methanol, butnot affecting glycerol conversion.

The main gas products for glycerol reforming are primary products H2, CO, CH4, C2H4, and C3H6, while CO2,C2H6 and C3H8 are most likely formed as secondary gas phase reaction products. Overall, the carbon fed asglycerol ends up in carbon oxides and hydrocarbons with a product ratio of roughly COx:CyHz = 2:1. Theratios of CO:CO2:H2 can be steered by the operating conditions. The overall mechanism of glyceroldecomposition seems to be through the dehydration of 1 water molecule and is independent of the presence ofNa+ in the glycerol.

The influence of five different catalysts was also determined. All catalysts not only promote the carbon-to-gasefficiency but also the water-gas shift reaction. The methanation reaction reaches equilibrium only for the Ni-containing catalysts at the higher temperatures, and appears limited for the other. The gas composition is astrong function of temperature. For some catalysts coke formation was observed and these catalysts steadilylost activity over time. In experiments using other catalysts coke formation was negligible, however, one ofthese latter disintegrated and lost its solid structure, while it retained its activity. Except for one catalyst thecatalyst structure remained largely intact in supercritical water and only minor changes in the support structurewere observed. The surface area of all porous catalysts decreased. The stoichiometric number (SN) of the gascompositions for the different catalyst is below 1 and therefore not attractive for methanol synthesis.However, two of those catalysts have very good potential for the production of ‘green’ natural gas.

WP2: SuperMethanol: synthesis and end-uses

IntroductionMethanol is mostly produced from synthesis gas. Synthesis gas consists of predominantly H2 and CO (plussome CO2 and CH4), that can be derived from steam reforming of natural gas or coal gasification. Threereactions can be used to define the equilibrium composition of gas mixtures used for the synthesis ofmethanol: Hydrogenation of CO (eq. 2.1), hydrogenation of CO2 (eq. 2.2), and the water-gas shift reaction(eq. 2.3):

CO + 2 H2 CH3OH H298 = -90.64 kJ/mol (eq. 2.1)

CO2 + 3 H2 CH3OH + H2O H298 = -49.47 kJ/mol (eq. 2.2)

CO + H2O CO2 + H2 H298 = -41.17 kJ/mol (eq. 2.3)

Both methanol synthesis reactions (eq. 2.1 and 2.2) are exothermic and proceed under volume contraction.The reactions are equilibrium reactions and reversible. The progress of the reactions is restricted bythermodynamic equilibrium. Most favourable conditions for methanol synthesis concerning reaction rate andposition of the equilibrium are high pressures and relatively low temperatures (P > 150 bar and T < 250oC) ascan be seen in Figure 2.1. Methanol synthesis at these conditions had not been explored yet and was the focusof WP2.

Figure 2.1 CO + CO2 equilibrium conversion for methanol synthesis as function of temperatures and at 4pressures. Feed gas composition: H2/CO/CO2/CH4 = 65/25/5/5 vol%).

TargetsWP2 focussed on the production of SuperMethanol from artificial gas at high pressure and relatively lowtemperature. The work included the development and screening of catalysts suited for methanol synthesis.Methanol synthesis experiments were conducted in packed bed reactors and other reactors if required. Thetargeted syngas conversion is over 90% and the influence of the process conditions and gas compositions wereinvestigated. Finally the SuperMethanol was used to synthesise biodiesel and compare the properties of this‘SuperBiodiesel’ with conventional Acciona biodiesel and the European standard EN 14241 for biodiesel(FAME)..

Task 2.1 Catalyst screening and selection (BIC, RuG)Extensive catalyst screening was performed. Finally three catalysts were selected for further testing of whichthe HTK catalyst showed the best results. The activity of the HTK catalyst was compared to a commercialcatalyst (BBG-2). The commercial catalyst turned out to be a little more active than the HTK catalyst (seeFigure 2.2) and it was decided to continue research on the BBG-2 catalyst.

Figure 2.2 Screening of the catalyst activity of BBG-2 (green, blue, and red line) and HTK. P = 8 MPa, feedgas composition: H2/CO/CO2/N2 = 66/24/6/4 vol%.

Task 2.2 The in situ formation of a liquid phase (RuG, BTG)Experiments with the BBG-2 catalyst were conducted at high pressure and relatively low temperature. Someunexpected results from this high pressure methanol synthesis will be elucidated. These results were obtainedin a so-called view cell, as shown in Figure 2.3A.

Figure 2.3 View cell (A), stirrer with catalytic chain (B)

A transparent sapphire window allows the observationView cell reactors have been used for investigating phaand the visual observation of precipitation. Its potentialalso recognised. The fresh catalyst wound around a stirrethe view cell after activation in Figure 2.3c. The catalyphase.

Most strikingly and the most relevant observation herephase is produced. Liquid formation started at the bobserved at the catalyst surface or the stirrer. Probabsurroundings preventing condensation on its surface. Thand part of the catalyst became immersed in the liquid ph

A

, activated catalyst (C).

of the phenomena taking place inside these behaviour, the determination of phase efor chemical reactions and in situ spectror is shown in Figure 2.3b and the activated

st became red which is the colour of the ac

at these conditions, is that in situ a liquidottom of the reactor and no droplet formly the catalyst surface is slightly warmee liquid level rose steadily during methanoase.

B

view cell.quilibriumscopy wascatalyst intive metal

methanolation wasr than thel synthesis

C

High pressure methanol synthesis with in situ formation of a liquid phase is beneficial for methanol synthesis,because: Higher conversion than predicted by gas phase thermodynamics can be obtained, resulting in almost

complete conversion of the limiting component. As the reaction rate is heavily influenced by the gas phase equilibrium higher reaction rates can be

obtained than in gas phase methanol synthesis. Reaction rates are a function of the partial pressure. Due to high partial pressures higher reaction rates

than in conventional methanol synthesis are obtained. Recycle streams can be omitted due to the high conversion of the feed gas. As a consequence of all the points mentioned above the reactor volume can be reduced. Due to the absence of recycle streams no build up of inert components occurs.

Development of an equilibrium model (Maribor, RuG)When condensation takes place during methanol synthesis, conventional gas phase equilibrium calculations donot suffice. A model was developed to calculate the equilibrium including phase and chemical equilibrium.Both the phase and chemical equilibrium in methanol synthesis are presented is a single diagram in whichclearly a vapour-liquid area can be distinguished. The shape of the diagram appears to be a strong function ofthe composition of the syngas feed. A modification of the Soave-Redlich-Kwong equations was used tocorrect for non-ideality.

The equilibrium conversion of CO+CO2 for a syngas with the following composition H2/CO/CO2/CH4 =70/5/20/5vol% is given in Figure 2.4. The figure contains four lines. Line 1, the solid line, is the gas phaseequilibrium. Line 2, the dashed line, is the conversion at which a dew point is reached. Line 3, the dotted line,is the equilibrium if both chemical and phase equilibria are met, and line 4, the dashed-dotted line is anextrapolation of the gas phase equilibrium line (line 1) to lower temperatures.

The extrapolation of the gas phase curve is the equilibrium conversion that will be obtained if dew points areabsent. The equilibrium conversion is much higher when a liquid phase of methanol and water with dissolvedgases is formed and thus chemical and phase equilibrium are met. The difference between chemicalequilibrium, and the combination of chemical and phase equilibrium is indicated by the arrow marked ‘B’ inFigure 2.5. The value of ‘B’ is the difference in conversion that is gained due to condensation.

Figure 2.4 Example of an equilibrium conversion diagram including chemical and phase equilibrium. P =20.3 MPa, feed gas: H2/CO/CO2/CH4 = 70/5/20/5 vol%.

High pressure methanol synthesis (RuG, BTG)A thorough study of once-through high pressure methanol synthesis was performed in a packed bed. Thetemperature and pressure were varied for 4 different feed gas compositions. Methanol was successfully

synthesised from all feed gases. Liquid product and gas products were analysed and quantified to establishmass balances.

The syngas conversion increased with increasing pressure and decreasing temperature as thermodynamicsdictate. In high pressure methanol synthesis (15 - 20 MPa) a liquid phase is formed in situ and this leads tohigh equilibrium conversions (see Fig. 2.5).

Figure 2.5 Equilibrium diagram for methanol synthesis including a dew point curve for CO+CO2 (A) and H2

(B). Feed gas: H2/CO/CO2/CH4 = 68/24/3/5 vol%. Symbols: experimental data; lines: model results.

The high conversions measured at these conditions can be accurately predicted with the equilibrium model.The equilibrium conversion at high pressure and low temperature were high and the limiting components areas good as completely converted. Conversions up to 99 % of the limiting components were reached, which ishigher than the target set at the start of the project. The formation of higher alcohols in methanol synthesis wasa function of the temperature and the feed gas composition. Higher temperatures and increasing CO partialpressures led to more higher alcohols. No clear relation between the formation of higher alcohols and pressurecould be established. When methanol was mainly synthesised from CO2 the purity of the organic phase was atleast 99.9 wt%.

Production of biodiesel from SuperMethanol (BTG, RuG)Biodiesel was produced from several SuperMethanol batches produced at high pressure. A biodiesel synthesisprocedure was taken from literature. For these experiments sunflower oil was taken as vegetable oil. Fourdifferent methanol samples were used; pure methanol, SuperMethanol with approximately 30 % of water,distilled SuperMethanol, SuperMethanol with the highest higher alcohol content (approximately 10 wt%). Thedensity, viscosity, water content, carbon residue, acid number, and metal content were analysed and comparedto the European standard (EN 14241), biodiesel from pure methanol, and Acciona biodiesel. Some results areshown in Figure 2.6.

When pure methanol was used all properties analysed were within the norm confirming the adequacy of thesynthesis method. Only for samples with a high water content (>10wt%) viscosities exceeding the limit anddensities close to the higher limit were measured. All other properties of the other experiments were wellwithin the norm and close to the values for Acciona biodiesel even for higher alcohol percentages up to10wt%.

Figure 2.6 Density, water content, and viscosity of the biodiesel produced with different (super)methanolsamples. SuMe = SuperMethanol, HA refers to a higher alcohol concentration of 10 wt%, H2O refers to awater concentration of 30 wt%.

ConclusionA commercial methanol synthesis catalyst was used for high pressure methanol synthesis from artificial gas.Methanol was successfully synthesised over a range of temperatures in a view cell and a packed bed reactor.At the combination of high pressure and relatively low temperature condensing methanol was observed in theview cell. Methanol condensation has a huge impact on methanol synthesis as much higher conversions can beobtained than in a gas phase reaction without the formation of a liquid. The equilibria including condensationwere modelled and the model predictions correspond nicely with experimental data.

Almost complete conversion of the limiting components in methanol synthesis were obtained fulfilling theresearch target of 90% conversion set in the WP description. Relations between the operating temperature, gascomposition, and SuperMethanol product were established. Biodiesel could be successfully produced fromSuperMethanol samples with a low water content. The presence of higher alcohols did not influence thequality of the biodiesel negatively of positively.

As a consequence of the observation of liquid methanol a lot of work was dedicated to understand and predictthis phenomenon, rather than testing additional catalyst in the view cell and packed bed reactors. Theformation of liquid methanol is investigated in a view cell and an extensive model was developed to predictthe simultaneous chemical and phase equilibrium. The work conducted in this WP will eventually lead to 3publications in peer-reviewed journals.

WP3: Process modelling

IntroductionWP3 concerned the modelling and simulation of main process steps i.e. glycerine reforming and methanolsynthesis. The intention of these models is to generate additional know-how on the pilot plant design (e.g. heattransfer, CO2 liquefaction, reactor design), to assist in the design of the demonstration unit (see WP5), and toprovide a learning tool. The modelling work also helped the project consortium to justify processconfigurations, reactor choices (both for RSW and methanol synthesis - packed bed, trickle flow reactors,mixing tank, etc.), and to establish (im)possibilities for water and / or CO2 recycle streams.

TargetsThe aim of this WP was to provide data regarding the optimal syngas composition for methanol synthesis andthe thermodynamic models that can be used for process design. This information was intended to support theexperimental research (WP1 and WP2) and the design of the pilot plant (WP4) and the demo unit (WP5).

Task 3.1 Analysis biomass reforming in water at supercritical conditions (MARIBOR, BTG)A literature survey was performed to assess biomass reforming in supercritical water. The research studiespublished by different groups were reviewed and summarised. For each study, the review focused on type ofcatalyst, reaction conditions, type and set-up of the reactor and products. When available, the thermodynamicsand kinetics of the reactions were also reviewed. The data were compared to the experimental results obtainedon glycerol reforming with supercritical water (WP1) and further used for process modelling.

Task 3.2 Analysis / modelling methanol synthesis (RUG, BTG)An adiabatic model was developed to describe the methanol synthesis from syngas in a packed bed reactor.The average composition considered for the syngas was H2 (50 vol%), CO (20 vol%), CO2 (10 vol%), CH4 (5vol%) and C2+ (5 vol%). Main reactions included in the model are the hydrogenation of CO and CO2 tomethanol and the water-gas shift reaction. Hydrocarbons are considered as inert components. A one-dimensional heterogeneous system (the reactions take place at a solid catalyst surface) and a numericalapproach were selected to reduce model complexity. Thus, it was assumed that radial gradients in the reactorare negligible. The various mass and energy transport mechanisms were taken explicitly into accountincluding possible mass transfer limitations (at inter- and intraparticle level). The model output can be used tooptimise reactor performance (concentration profile of the components in the gas bulk, temperature profileacross the reactor, catalyst performance). The adiabatic model was then extended with heat withdrawal by acooling medium, the described process becoming similar to methanol synthesis in practice.

Another aim of the study was to establish the influence of operating conditions (pressure, inlet temperature ofsyngas, temperature of coolant) on the performance of methanol synthesis reactor. To simulate the reactorbehaviour at steady-state conditions under various conditions a sensitivity analysis was performed usingAspen Plus software and Soave-Redlich-Kwong and Peng-Robinson equations of state. The monitoredvariables were molar conversion of CO, pressure drop across the reactor length, mass fraction of methanol inthe reactor outlet stream, and maximal temperature of the bulk gas reached along the reactor length. Theresults indicate that the system favours high pressures (Figures 3.1 and 3.2), however, at pressures higher than210 bar the conversion of CO increases only slightly with the increasing pressure. At 210 bar a 95%conversion of CO is predicted. An expected mass fraction of methanol in the product stream is approximately30% given the presumed composition of syngas. Pressure drop at the studied conditions is negligible and isestimated to be in the range of 0.05 bar to 0.1 bar given the studied reactor configuration. The results alsoindicate that the coolant temperature should be above 195°C to assure significant conversion of CO and below225°C to prevent the bulk gas reaching temperatures over 300°C.

Figure 3.1 Effect of pressure (-■-) and temperature (‒♦‒) on methanol yield (SRK-EOS).

Figure 3.2 Effect of pressure (-■-) and temperature (‒♦‒) on methanol yield (PR-EOS).

Additional simulation was performed using Aspen Plus software and Peng-Robinson’s equation of state (PREOS) to estimate thermo-physical properties of the reaction mixture. The kinetics was taken from theliterature. The results presented in Figures 3.3-3.7 correspond to those obtained by varying the syngas inlettemperature (TIN) and inlet-stream pressure (pIN).

Figure 3.3 Conversion of CO as a function of inletconditions (T, p).

Figure 3.4 Methanol mass fractions in the reactoroutlet-stream as a function of inlet conditions (T, p).

Figure 3.5 Pressure drop across the reactor as afunction of inlet conditions (T, p).

Figure 3.6 Conversion of CO a function of syngasinlet and coolant temperature.

Figure 3.7 Maximal bulk gas temperature as a function of syngas inlet and coolant temperature.

Task 3.3: Flow sheeting: process M&E balances (BTG, RUG, MARIBOR)The goal of this research was to perform a computer simulation of a methanol production process throughwhich preliminary energy and mass balances were established. The simulation was performed using AspenPlus software (AspenTech, USA). Thermodynamic properties were calculated using Predictive Soave-Redlich-Kwong (SRK) equation of state. The process, as simulated (Figure 3.8), comprised three sections:reforming of glycerol to syngas with supercritical water, synthesis of methanol from syngas and processing ofcrude methanol. The obtained results indicate that a plant operating 8000 h/a and reforming 3000 t/a ofglycerol is capable of producing approximately 1000 t/a of methanol (w > 99.5 %). Some of the physicalproperties of streams are given in Table 3.1.

GomGaas

Legend: C - compressor; DC1–DC2 - distillation columns; GLYSCW – glycerol super critical water reformer; HX1–HX4 - heat exchangers, M -mixer; R - reactor; S1–S2 - splitters; T - turbine; X - flash.

Figure 3.8 Methanol production process flowchart.

lycerol (1) is fed to a glycerol reforming unit (GLYCSW) where it is converted to syngas. For the purposesf this research it was assumed that the gas produced (2) in the GLYSCW is composed of hydrogen, carbononoxide, carbon dioxide, methane, impurities (higher alcohols, acids, etc.) and water. The syngas exiting theLYSCW needs to be cooled from approximately 750 °C to 230 °C before being fed to the reactor (R). In

ddition, the pressure must be adjusted to reactor operating pressure of approximately 60 bar. The latter can bechieved by cooling and pressure relief (route (3)–(4)) or by feeding the hot gaseous mixture to a turbine andubsequent cooling (route (3a)–(3c)). The latter is, however, due to low mass flow rate (qm < 500 kg/h)

technologically and economically questionable. The syngas is converted to methanol in a tubular reactoroperating at 59 bar and 230 °C, where the following reactions take place:

2 3CO + 2H CH OH ΔH300K = –90.77 kJ/mol (1)

32 2 2CO + 3H CH OH + H O ΔH300K = –49.16 kJ/mol (2)

2 2 2CO + H O CO + H ΔH300K = 41.21 kJ/mol (3)

Table 3.1: Stream data.

*impurities (IMP)

The mixture leaving the reactor (6) is cooled in a heat exchanger (HX3) and flashed in flash (X). The gaseousstream (8) is recycled. To prevent a build-up of mass in a recycle a fraction of stream (8) is purged. Aftercompression (C), the recycle stream is mixed with fresh syngas (M). Crude methanol (13) leaving the flashunit (X) is processed in a two-column sequence. The first column (DC1) is a stripping column, where low-boiling gases (CO2, methane, etc.) (14) are separated from methanol, water and higher-boiling impurities (15).The second column (DC2) is a rectification column where methanol (w > 99.5 %) is obtained as a distillate(16). The bottom product (17) is composed mainly of water and higher-boiling impurities.A more general flowchart model was also developed to establish the complete mass and energy balances forthe entire integrated concept, to provide data for the design of a demo unit. This model, incorporating the datagenerated in WP1 and WP2, was adjusted to include recycle streams, improvement in conversion – gascomposition data, to steer operating temperatures towards optimal gas conversion (methanol synthesis) as wellas to analyse / use solubility data.

ConclusionThe available thermodynamic data in the literature were reviewed and completed with the results obtainedduring the experimental research (WP1 and WP2). The data were used to model the entire process and,separately, methanol synthesis. Aspen Plus software and Soave-Redlich-Kwong and Peng-Robinson equationsof state were used for process simulation. The results suggest that up to 210 bar methanol synthesis isfavoured by increasing pressure, increasing only slightly afterwards. The effect of syngas inlet temperatureand inlet-stream pressure on process output was also analysed.A flowchart of the entire process was also generated and the data for each stream in the process werecalculated. The flowchart model was further completed with mass and energy balances to provide data for thedesign of a demo unit.

Stream°C

T

bar

p

kg/hmq

%

w

CH4 H2 CO CO2 CH3OH H2O C3H5(OH)3 IMP*1 20 1 375 / / / / / / 100 /2 750 100 413 7.7 4.8 26.9 42.3 / 9.1 / 9.13 750 100 413 7.7 4.8 26.9 42.3 / 9.1 / 9.14 230 59 413 7.7 4.8 26.9 42.3 / 9.1 / 9.15 230 59 3829 16.2 2.0 6.6 72.6 0.5 1.0 / 1.06 230 55 3829 16.2 1.6 3.9 72.2 3.9 1.2 / 1.07 30 50 3829 16.2 1.6 3.9 72.2 3.9 1.2 / 1.08 27 40 3597 17.3 1.7 4.2 76.3 0.6 / / /9 27 40 180 17.3 1.7 4.2 76.3 0.6 / / /10 27 40 3417 17.3 1.7 4.2 76.3 0.6 / / /11 57 60 3417 17.3 1.7 4.2 76.3 0.6 / / /12 230 59 3417 17.3 1.7 4.2 76.3 0.6 / / /13 27 40 233 0.3 / / 9.7 55.1 18.7 / 16.114 25 1.5 25 3.0 0.1 0.4 90.3 5.8 0.4 / /15 93 2.1 208 / / / / 61.0 20.9 / 18.116 75 1.5 126 / / / / 99.6 0.4 / /17 126 2.1 82 / / / / 1.5 52.6 / 45.9

WP4: Pilot plant design, setting up and experimental testing

IntroductionTo synthesise methanol from glycerol-derived syngas the two processes described in WP1 and WP2 need to

be integrated. The stoichiometric ratio (SN) of a syngas is defined by , and ideally SN = 2 as at

this ratio all carbon oxides can be converted to methanol. Theoretically, for glycerol it is not possible to obtaina syngas with an SN of 2 and assuming glycerol decomposes only in H2, CO, and CO2 the SN becomes 1.33.The SN can be improved by the addition of H2 or the removal of CO2. The largest amount of methanol can beobtained if only the following reaction takes place:

3 C3H8O3 + 2 H2O 7 CO + 14 H2 + 2 CO2 7 CH3OH + 2 CO2

Theoretically 2.3 carbon molecules/mole glycerol end up in methanol, which corresponds to a carbon yield of78%. On a mass bass it is theoretically possible to produce a maximum of slightly more than 0.8 kgmethanol/kg glycerol. In the RSCW experiments the gas composition and yield that can be obtained fromglycerol was investigated as function of the process conditions. In these experiments a clear and rather uniquerelation between the carbon-to-gas efficiency (CGE) and the gas yield could be found. The CGE appears to berelated to the process conditions and from this relation the gas composition can be calculated. The gascompositions derived from glycerol/RME glycerine are not very attractive for methanol synthesis and have anSN far below the highest possible value of 1.33. This is mainly due to the high quantity of hydrocarbonsproduced, more specific CH4. Nevertheless, it is possible to produce methanol out of such a syngas andtherefore the functionality of the PDU can be demonstrated.

WP4 TargetThe overall objective of this work package is to demonstrate the GtM process. Specific measurabledeliverables are to demonstrate glycerol conversions > 90% to produce a syngas with H2/CO > 1, CO2 < 20vol.%, (CH4+C2+) concentration < 10%, and subsequent conversion to methanol yielding over 90% on syngas.Later the restrictions H2/CO > 1, CO2 < 20 vol.% were abandoned because methanol could also besuccessfully synthesised from CO2-rich gas. The target is to obtain a overall yield of 50% methanol fromglycerol.

Task 4.1 Overall design of the pilot plant (UHPT, BTG, Maribor, RUG, Sparqle) &Task 4.3 Construction of the pilot plant (BTG, UHPT, Maribor, RUG)Based on separate reforming and methanol synthesis experiments, first mass and energy balances weregenerated for a pilot plant set-up. The unit is a combination of two processes. The first process is a small-scaletest rig for the reforming of biomass in SCW, the other a set-up in which the methanol synthesis reaction canbe carried out at high pressures. Combination of these two rigs allows integration, to demonstrate the overallconcept of reforming and methanol synthesis. A short summary of results obtained in laboratory units can belisted as follows:

Experimental work on the reforming of glycerol shows that at limited conversions relatively high COproduction rates are observed, whereas at high conversions mainly CO2 is produced. For methanolsynthesis, high CO concentrations (>25%) and rather low CO2 concentration (<10%) are initiallypreferred. Later on the focus shifted to methanol from CO2;

No carbon deposition is observed in glycerol reforming: recycling of unconverted glycerol is thuspossible;

Ash in the glycerol (crude) yields higher CO2 concentrations at high glycerol conversions only (mostprobably due to the shift reaction). At the lower glycerol conversions, there is no significant difference inCO2 yields between ash containing and pure glycerol;

Ash present in the glycerol at a concentrations > 1000 ppm at 500oC (and lower at higher temperatures)will deposit inside the reforming reactors.

A consistent set of data on yields (H2, CO, CO2, CxHy) as a function of the glycerol conversion has beenprepared;

A relationship between temperature and residence time (the ‘‘T-- relation’) in the RSCW reactor for 30%and 50% conversion of glycerol has been prepared and the ‘best’ operating temperature / reactor volumesare yet to be established;

In the methanol synthesis CH4 and other CxHy are inert; Methanol synthesis can be carried out at 200oC inlet temperature. A cooled packed bed reactor can be

taken as basis for design.

Figure 4.1 Process demonstration unit (PDU) integrating all processes

An extensive data set has been obtained from the laboratory units and this allowed a proper first design of theconcept, which is depicted in Figure 4.1. The unit can be operated with or without tail water recycle. It wasfound that the gas upgrading process can be omitted because it requires a lot of energy to improve the gascomposition for the subsequent methanol synthesis. The scale of the set-up chosen has been carefullyconsidered in terms of practical reasons (ease of modifications, costs of equipment and so on) and relevancefor further scale up (interpretation in terms of a design for a demo unit). As the system merely deals with gas-liquid reactions over catalysts packed bed systems, a rather small scale unit (1 L/h liquid flow rate) appearedmore than sufficient.

Task 4.3 Experimental programme pilot plant (BTG, UHPT, RUG, Maribor, Sparqle, BIC, Acciona)The pilot plant was used to proof the GtM concept on small scale. In this test programme, all relevant findingsdiscovered in all previous work packages were included. The final results of this test programme enable thebasis of the design for the demo unit.

In a first proof-of-principle experiments (no recycle of tail water) of 30 h, the methanol yield was rather low(0.1 kg MeOH/kg glycerol) due to the incomplete conversion of glycerol, the lack of H2 in the gas, and thehigh quantity of hydrocarbons. This was improved by increasing the temperature/residence time of the system(similar as by recycling unconverted glycerol) and adding additional H2 to the system respectively (see Table4.1 for the results). Due to the addition of H2 several aspects of the process change. The feed gas compositionchanges to a gas with an excess of H2 and an SN of 2.66 but also the gas flow through the methanol synthesisreactor changes. Comparing the experimental gas composition with the equilibrium gas composition it can beseen that the equilibrium is not reached at these conditions. The residence time in the catalyst bed is probablytoo short at these conditions (low temperature).

Table 4.1 Results of methanol synthesis from glycerol-derived syngas

Exp v,out H2 CO CO2 CxHy L. yielda Yield CH3OH H2O CO+CO2 H2 CGtMb Cbal

(L/h) (vol%) (vol%) (vol%) (vol%) (g/h)(kg MeOH/kg gly)

(wt%) (wt%) (%) (%) (%) (%)

1 37.1 3.3 2.2 43.6 50.9 28.9 0.27 100.0 0.0 57.5 97.4 26.1 95.0

Equi 38.5 4.4 1.9 43.8 49.9 30.1 0.28 97.4 2.6 56.0 96.4 26.5 100

2c 136.6 67.3 2.9 13.3 16.4 31.9 0.27 94.3 5.7 49.7 34.4 25.7 100.3

Equi 60.4 59.7 0.0 0.2 40.1 70.9 0.49 78.3 21.7 99.7 74.3 49.1 100

3c 88.9 65.8 0.3 6.9 26.9 56.1 0.40 79.4 20.6 81.0 58.3 38.2 97.7

Equi 80.0 63.4 0.5 6.1 30.0 59.9 0.43 80.4 19.6 88.0 63.8 43.6 100

a: Yield of liquid productsb: Conversion of carbon in glycerol to carbon in methanol

In experiment 3 the operating temperature of the reactor was increased. Approximately 88 % of the carbonoxides present in the high pressure gas were converted to methanol. 38.2 % of the carbon originally present inglycerol ends up in het methanol, which is equal to 0.40 kg MeOH/kg glycerol. The highest methanol yieldfrom glycerol was obtained when H2 is added to the HPS gas. From an thermodynamic point of view lowertemperatures are favourable, but from a kinetic point of view these temperatures are required.

Surprisingly, it was found that CO2 can be hydrogenated to methanol at reasonable reaction rates. The strategyto demonstrate higher carbon conversion from glycerol to methanol was adapted from adding extra hydrogento modifying the GTM-PDU, adding the SMC-1 catalyst in the reforming section and changing the reformingreaction conditions, to produce methanol from a gas mixture containing mainly H2, CO2, and CH4.

The modifications included:1. Tail water recycle; Part of the syngas is lost via the tail water leaving the system (see Figure 4.1). Gas loss

can be prevented by recycling the tail water instead of depressurizing and removing the water and thedissolved components from the system. A high pressure recycle was incorporated into the systemincluding a recycle pump. Glycerol is in this system not premixed with water but injected in the waterstream before the first reforming reactor.

2. Use of the SMC-1 reforming catalyst combined with a higher reforming temperature; One of therestrictions on the methanol yields is the gas composition. A significant amount of hydrocarbons ends upin the gas and these components are inert. By using a methane reforming catalyst in combination withsomewhat higher temperatures all hydrocarbons except for CH4 can be reformed yielding a morefavourable gas composition. The CH4 concentration will be at its equilibrium composition.

3. Addition of an extra methanol synthesis packed bed; The methanol section consists of 3 packed bedreactors. Methanol synthesis from CO2 is slower than from CO. An extra bed is added to compensate forthe slower reaction rate.

4. The system is operated with different temperatures of the packed bed reactors; The heating oil is suppliedto the first reactor and allowed to cool slightly between the reactors. The reaction rate in methanol

synthesis depends strongly on temperature. Higher temperatures lead to higher reaction rates. In the firstreactor the reaction rate will be relatively high while the second and third are used to achieve highconversions.

Table 4.2 Reforming results (before methanol synthesis)

Exp P v,gly v,out H2 CO CO2 CxHy SN glya Cbal

(bar) (g/h) (L/h) (vol%) (vol%) (vol%) (vol%) (-) (%) (%)

4 240 97 151.4 54.9 1.6 32.5 11.0 0.66 99.9 97.1

5 240 97 151.4 54.9 1.6 32.5 11.0 0.66 99.9 97.1

6 240 38 69.5 61.4 1.1 32.1 5.3 0.88 99.9 98.9

7 240 35 64.8 59.4 1.1 33.5 6.0 0.75 99.9 103.7

8-1 260 33 58.6 59.7 1.0 32.2 7.1 0.83 99.9 98.5

8-2 260 35 70.7 66.4 1.3 30.0 2.4 1.17 99.9 95.0a: Cannot be measured, because the set-up is operated in recycle mode. The conditions are such that 99.9% isexpected.

Before methanol synthesis was conducted, glycerol reforming was conducted. The results are shown in Table4.2. The composition of the gas after reforming contained mainly H2, CO2, and CH4. The CO and C2H6 (max0.5 vol%) content was very low and no other hydrocarbons were detected. The lowest hydrocarbon contentwas measured for experiment 8-2.

The results of experiment 4-8 are given in Table 4.3. The methanol yield went up from exp. 4 to exp. 5 from0.29 to 0.39 kg MeOH/kg glycerol (28 to 37 % carbon conversion) due to an increase of the packed bedtemperature and the final gas composition of the latter experiment was close to equilibrium.

To produce more than 0.5 kg MeOH/kg glycerol the temperature of the packed bed should be reduced, but inexperiment 4 that the equilibrium was not reached. The glycerol feed quantity was reduced with a factor of2.6-3. Another advantage of lowering the feed quantity is the more favourable gas composition (less CH4) formethanol synthesis (see Table 4.2). At lower temperatures, the gas composition and the yields remained farfrom equilibrium and no yield increase was observed compared to experiment 4 and 5. A 10 oC higher(experiment 7) resulted in an increase of the methanol yield to 0.48 kg MeOH/kg glycerol (carbon conversion= 46 %), but still below the equilibrium yield. The system remained kinetically limited, although the feed flowto the packed bed was reduced. The gas preheater was turned into a reactor for experiment 8. In thisexperiment 3 packed bed reactors in series were used. The methanol yield for this experiment was 0.55 kgMeOH/kg glycerol (carbon conversion = 53 %), which is even higher than the equilibrium yield. Experiment8-2 is a duplicate experiment and was conducted for 20 h. The amount of hydrocarbons in the gas is lowerresulting in methanol yields of 0.65 kg/kg glycerol which is equal to a carbon conversion of 62 %.

Converting more than half of the weight of glycerol to methanol is thus possible, but requires high reformingtemperatures and low feed concentrations. Interestingly, if limited amounts of hydrogen are added (20 NL/h)yields up to 0.7 kg methanol/kg glycerol are expected.

Table 4.3 Results of methanol synthesis from glycerol-derived syngas

Exp Glyin v,out H2 CO CO2 CxHy L. yielda Yield CH3OH H2O CO+CO2 H2 CGtMb Cbal

(g/h) (L/h) (vol%) (vol%) (vol%) (vol%) (g/h)(kg MeOH/kg gly)

(wt%) (wt%) (%) (%) (%) (%)

4 97 82.5 41.6 0.4 40.0 18.1 41.3 0.287 67.1 32.9 35.4 58.8 27.5 96.3

Equi - 60.4 25.5 0.7 46.1 27.6 50.3 0.344 66.1 33.9 45.1 81.5 32.9 100

5 97 67.3 34.4 0.4 42.6 22.5 56.8 0.389 66.0 34.0 43.8 72.2 37.2 100.1

Equi - 71.6 33.1 1.3 42.4 23.3 44.2 0.301 65.8 34.2 39.4 71.5 28.9 100

6 35 33.9 48.9 0.6 39.9 10.7 14.4 0.260 63.9 36.1 39.0 57.0 25.0 92.6

Equi - 16.6 15.1 0.6 61.1 23.2 26.7 0.493 65.2 34.8 54.3 93.5 47.3 100

7 38 22.5 37.9 0.4 44.9 16.8 27.1 0.476 66.2 33.8 56.0 80.0 45.6 97.4

Equi - 16.9 20.4 0.8 57.7 21.1 29.2 0.505 65.2 34.8 57.3 91.9 48.4 100

8-1 34 12.5 15.7 0.3 53.4 30.6 28.3 0.55 66.1 33.9 66.4 94.5 52.8 94.6

Equi - 15.0 13.2 0.5 57.1 29.1 25.9 0.50 65.1 34.9 56.5 94.5 47.6 100

8-2 35 10.9 20.0 0.3 59.5 20.2 33.4 0.62 65.1 34.9 70.5 95.4 59.6 94.0

Equi - 9.5 10.8 0.6 69.6 19.0 34.7 0.65 65.3 34.7 70.0 97.8 62.1 100

a: Yield of liquid productsb: Conversion of carbon in glycerol to carbon in methanol

ConclusionThe integrated GTM-PDU is investigated to demonstrate the glycerol-to-methanol concept. In a continuousrun of over 30 h glycerol is successfully converted into methanol, demonstrating the functionality of thesystem. The overall conversion of carbon in glycerol to carbon in methanol (10 %) is rather low. This is due tothe unfavourable composition of the gas derived from glycerol and the incomplete conversion of glycerol.

The methanol yield was increased in a modified GTM-PDU aimed at producing only H2, CO2, and CH4 in thesyngas. When an extra methanol synthesis bed was added to the GTM-PDU and the packed bed were operatedat different temperatures a carbon conversion of 62 % which is equal to 0.65 kg methanol/kg glycerol. Thelatter yield was obtained in an experiment with a run time of 20 h.

WP5: Design of a demonstration unit

IntroductionThe objective of WP5 is to come to a GO - NO GO decision to start building a full-scale demo unit at thepremises of ACCIONA’s biodiesel plant in Caparroso (Navarra, Spain), see Figure 5.1.

Figure 5.1: ACCIONA’s biodiesel plant in Navarre.Envisaged location for a full-scale demo plant for SuperMethanol

WP targetsA blueprint will be prepared for such GtM demo unit, and the possibilities and requirements for its integrationin ACCIONA’s biodiesel production plant will be analysed. A further outcome is an economic evaluation ofthe GtM process to assess the methanol production price.

Task 5.1 Basis of design (ACCIONA, UHPT)The main purpose of task 5.1 was to define and establish basic constraints and requirements of the GtM demounit, to serve as initial and preliminary step for the subsequent development of the GtM design/engineeringpackage. These constraints reflect that the GtM demo unit would be integrated with ACCIONA’s biodieselplant in Caparroso. First the system and its boundaries were defined, then the relevant input/output materialsand processes involved were identified, and finally the individual process steps were linked.

Task 5.2 Glycerine market studyThree versions of a glycerine market study were produced. A preliminary study was prepared in 2008,expanded in 2009 and updated in 2011. This approach was adopted to reflect that both the glycerine and themethanol market are very versatile, rendering market information outdated very quickly.

The 2009 edition focused primarily on technical matters. It aimed to establish “traditional” glycerine productsand production processes, and described both existing and innovative applications of glycerine. The reportpresented an outline of the production process, composition and main applications of the differenttypes/qualities of glycerine; described traditional and innovative uses of glycerine; discussed the glycerine(feedstock) and methanol (end product) markets as well as some opportunities for the production ofSuperMethanol and for product differentiation. The study provided the consortium with data on glycerineavailability and prices, its current uses, the R&D work being carried out and the actors important in this area.

In the 2011 version the market study was expanded, and also discussed (in more detail) the latest biodiesel andglycerine market developments and GtM process economics and financial implications. In 2011 the prices of(crude and pharma) glycerine were slightly higher than in 2009 (see Figure 5.2).

Figure 5.1: Glycerine price evolution (source: ACCIONA)

Task 5.3/5.4 Preliminary and final design (UHPT, ACCIONA, BTG, Sparqle)

Block diagram and process flow diagramA block diagram of the GtM process is presented in Figure 5.3 (next page). It shows the operation stepsinvolved in the process, and the inlet and outlet streams. The process includes a unit to remove salt fromglycerol prior to SCW-reforming.

Glycerol feed is heated up to conditions were it vaporises. In a separation step the vapour phase, whichcontains a significantly reduced content of salts, is separated from the liquid phase, which contains asignificantly high amount of salts. Glycerol vapour is mixed with recycle water, which contains 70 % of theoriginal glycerol feed, before entering the SCW-reformer. In the reformer, which is designed as a tube reactor,30% of the glycerol is converted into syngas. The syngas-mixture, which is leaving the SCW-reformer, iscooled down in counter current to the mixture, which is entering the SCW-reformer. In a separator syngas,after cooling, is separated from the water, which contains unconverted glycerol. This water is recycled. Theseparated syngas is heated up to the temperature for methanol synthesis and enters the methanol reactor,which is of shell-and tube-type.

In the methanol reactor syngas is converted into methanol. The methanol, which is leaving the methanolreactor contains unconverted gases, which will separated downstream from the methanol.

Together with the block diagram and the flow sheeting the process flow diagram was evaluated (seeDeliverable 5.23). It shows the main equipment and the connecting streams with their main properties.

Demonstration unitThe demo unit is operated in a continuous automatic operation. The equipment of the demo unit is designedto fulfil the requirements of the GtM-process in terms of pressure, temperature, flow rates, residence times.For the fabrication of the SCW-equipment high temperature and corrosion resistant alloy materials wereselected. Other equipment will be made of stainless steel.

As a result of the basic design of the equipment an arrangement of equipment and pipes was evaluated in a3D-model. An example of the 3D-model is shown in Figure 5.4.

Glycerine market evolution

0

100

200

300

400

500

600

2008 2009 2010 2011 2012

Years

€

crude glycerine pharma glycerine

Figure 5.3 Block Diagram of the GtM process

Glycerol Water

Feeding1 bar, 40°C

Feeding1 bar, 40°C

Ash Removal300 bar 500°C

Purge

Brine SCW-Reforming300 bar 600 °C

SyngasSeparation

300 bar 30°C

Tail WaterRecycle

Methan-Synthesis300 bar 200 °C

HP- Separation300 bar 30°C

LP- Separation1 bar -3°C

Waste Water

Methan-rich Gas

CO2-Rich Gas

Methanol

RSW Water

Reactor Feed

RSW-Gas

Recycle Water

Recycle Water

Vent

Syngas

EP 1

Heat 1 Heat 2

Heat 3

Heat 4

Heat 5

Heat 7

EP 2

EP 3

Heat 6

Figure 5.4 3D-view of GtM Demo Unit

Task 5.4. Final design and cost estimate (UHPT, ACCIONA, BTG, SPARQLE)The economic feasibility of the proposed demo unit has been determined by ACCIONA assuming that thefull-scale GtM process demo unit be integrated with an existing, operational biodiesel production plant. Twodifferent production capacities in a total of 5 scenarios, with associated investment and operational costs havebeen assessed, using input data provided by UHPT and BTG on investment capital, energy consumption andmass flow balances for each one of these scenarios (see Table 5.1). The main premises of each scenario are:

Scenario A1: Demo unit (1,000 t/hr glycerol) with 30 % conversion per pass including ash removal, crudeglycerol as raw material, Inconel 718 as material for the SCW-part. This is the base case for the design ofthe demo unit.

Scenario A2: Demo unit (1,000 t/hr glycerol) with 30 % conversion per pass including ash removal, crudeglycerol as raw material, Inconel 617 as material for the SCW-part.

Scenario B: Demo unit (1,000 t/hr glycerol) with 30 % conversion per pass including ash removal, crudeglycerol as raw material, Inconel 617 as material for the SCW-part, and including addition of H2 forimproved methanol yield.

Scenario C: Demo unit (1000 t/hr glycerol) with 100 % conversion (in single pass), without ash removal,cleaned glycerol as raw material, Inconel 617 as material for the SCW-part.

Scenario D: Production unit (3000 t/hr glycerol) with 100 % conversion (in single pass), without ashremoval, cleaned glycerol as raw material, Inconel 617 as material for the SCW-part.

Based on these data, the annual and specific production costs (in (€/year and €/t respectively) for methanolwere determined for each scenario. The results obtained are shown in Table 5.2 and Table 5.3.

These unitary production costs do not include the ones related to the crude glycerol used as raw material of theGtM process, due to the fact that the glycerine is obtained as a by-product of the running biodiesel productionplant to which the GtM process is intended to be attached.

Table 5.1: Investment costs, energy consumption and mass flow balances for scenarios A1, A2, C and D.

Table 5.2: Annual glycerine consumption, methanol production and cost savings

Based on the glycerine conversion rates for each scenario and the methanol and glycerine market prices forthe years 2006-2011, as listed in Table 5.2, unitary cost savings can be calculated as follows:

(Eur/Tn)PriceGlycerineFactorConversionGtM-(Eur/Tn)PriceMethanol(Eur/Tn)SavingCostUnitary

where

(Kg/hour)ProductionMethanolGtM

(Kg/hour)nConsumptioGlycerineGtMFactorConversionGtM

The resulting specific production costs are listed in Table 5.3. Figure 5.5 plots the specific production costs foreach of the four scenarios considered. All value lays below the break-evenline, indicating that under themarket conditions experienced in recent years the unit cost of producing methanol is higher than the savingsgenerated.

The relatively high cost obtained for the GtM process from this economic feasibility study is mainly due to thefollowing reasons: (i) the high value of CAPEX required for the implementation of the process, whichincludes very demanding and challenging equipments operating at very high pressures and temperatures and(ii) the huge energy consumption and associated cost involved to obtain the high operating pressures andtemperatures required for the GtM process.

Table 5.3 Unitary production cost and savings (€/t) for methanol production from the GtM process for eachscenario (plant scale and glycerine conversion rate) considered.

Figure 5.5 Specific savings versus specific costs for each of the fours scenarios

ConclusionsA major project outcome was the preparation of a blueprint (design package) for a full-scale GtM demo unit tobe installed at and integrated with the biodiesel production plant of ACCIONA in Caparroso (Navarra, Spain),In a market study glycerine and methanol markets were analysed. The study provided data on glycerineavailability and prices, its current uses, the R&D work being carried out and the actors important in this area.The economic feasibility of the proposed demo unit was determined. Under the market conditions experiencedin recent year the installation of the GtM unit at the scale considered (3,000 t/y glycerine input) is noteconomically viable due to high investment costs (associated with equipment operating at severe pressuresand temperatures) leading to high specific production costs. To be economic, a minimum scale of operation ofaround 10,000 t/y glycerine input would be needed.

IV. Potential Impact

According to the final obtained results, the project achieved the demonstration of the complete glycerine-to-methanol process on laboratory and pilot plant scale, obtaining conversion over 90%, and producing a syngaswith H2/CO over 1, below 20 vol.% CO2 and below 10 vol.% (CH4+C2

+). The overall achieved target is ayield of 50 wt% methanol from glycerine (energy efficiency over 70%).

In addition a detailed design for a full-scale methanol production facility integrated for a hypotheticimplementation in a commercial biodiesel production plant was completed. However the target to producemethanol at a price below 250 EUR per tonne was not achieved.

Academic impactThanks to the outstanding technical results of the project, several publications in peer-reviewed scientificjournals and a PhD thesis were published or planned.

In addition, thanks to these relevant technical results a patent titled “Application on the synthesis of methanolusing the syngas derived from the reforming in supercritical water” was applied by RUG and BTG on 4April 2011 with application number 2006535. The patent application text will remain confidential until 4October 2012.

These facts highlight the significant impact at academic level of the project research results and mean thebasis for the launching of forefront new research lines in the field of bio-energy chemical processing andrelated technologies for RUG and BIC. Thus, more specifically, RUG will open a new research line pursuingthe development of new synthesis methods of methanol using the syngas obtained from different biomass afterreforming in supercritical conditions (RSC) and BIC will continue working on the initiated investigations onnew and optimised catalysts for RSC syngas upgrading.

Industrial impactOn the other hand, although the developed GtM process, targeted to be integrated in an existing and operatingbiodiesel plant, has been proved to be technically feasible, it appeared not to be economically viable at themarket conditions experienced in recent years. At the current scale it may turn profitable when the prices ofglycerine and methanol change such that the unitary cost saving of the GtM process, as defined in previousChapter, becomes higher than 500 Eur/t.

This situation arises from the high investment costs, which includes equipment that operates at severepressures and temperatures, hence high provision materials, insulations, painting and so on are required. Theenergy consumption is also another critical issue because of the heating and cooling utilities needed toobtained the high operating pressures and temperatures required.

As a consequence, at least in the short-term, a market uptake by the biodiesel industry of the global andoverall GtM process developed in the SuperMethanol project cannot be expected. However, some of theconstituent sub-processes of the GtM unit, could be quickly adapted and used at large scale in another sectorsand fields of the chemical industry as it could be the case for: i) Reforming of Biomass on SupercriticalWater; ii) Syngas Upgrading Process; iii) Methanol Synthesis from High-Pressure Syngas. On top of that,with the technological achievements and acquired knowledge in the field of biomass reforming in supercriticalcondition, the consortium partners in general and coordinator BTG in particular strengthened their existingand well-recognised know-how on chemical processing of bio-energetic biomasses. In the case of BTG thiswill enable them to apply in a competitive way their core business activity: research and consultancy targetedat biomass-related chemical processes.

V. Website and contact details of project partners

PROJECT WEBSITE

www.supermethanol.eu

PROJECT CONSORTIUM

Coordinator: BTG Biomass Technology Group (Netherlands), www.btgworld.com

Technical coordination:Dr. Robbie VenderboschTel. ++31 53 4862281Email: venderbosch@btgworld.com

Project manager:Ir. John VosTel. ++31 53 4861191Email: vos@btgworld.com

Project partners

Acciona Servicios Urbanos(Spain)Dr. Miguel Angel Paris TorresR+D+I DepartmentTel ++34 91 791 2020 ext. 3987Email: miguelangel.paris.torres@acciona.esWeb: www.acciona.es

University of Maribor(Slovenia)Prof. Dr. Željko KnezLaboratory for Separation ProcessesTel. ++386 2 2294 461Email: zeljko.knez@uni-mb.siWeb: atom.uni-mb.si/labs/lab_sep/engindex.htm

Boreskov Institute of Catalysis(Siberia, Russia)Prof. Valery A. KirilovTel: +7 383 330 6187Email: vak@catalysis.ruWeb: www.catalysis.ru

UHDE High Pressure Technologies (Germany)

Dipl-Ing. Michael BorkTel. ++49.2331 967 288Email: michael.bork@thyssenkrupp.comWeb: www.uhde-hpt.com

Rijksuniversiteit Groningen(Netherlands)Prof. Dr. Ir. Erik HeeresTel. ++31 50 363 4174Email: h.j.heeres@rug.nlWeb: www.rug.nl/staff/h.j.heeres/index

SPARQLE International(Netherlands)Prof. Dr. J.M.L. (Jo) PenningerTel. ++31.74.291 6621Email: spql@introweb.nlWeb: http://www.sparqle.com