1. Introduction - Firenze University Press

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ineffectiveness of the catalyst, in which steam at 535 and 120bar is generated and sent to combined cycle subsystem for power. After the three reactors, the products is cooled down to 25 to remove water and then sent to a flash drum to separate a spot of methanol which is mixed in the SNG. SNG of over 93% CH4 (mole basis) is produced and the separated mixed methanol is sent for combustion in the combined cycle subsystem for power. As shown in Figure 4, the new system applies the serial connection between the chemical production process and power generation system: all of the syngas produced by gasifier enters the chemical production process at first, and after methanol production and SNG production, the unreacted gas is then sent to power generation subsystem. Compared with the single methanol and SNG synthesis production process, the new system has the following key features: (1) Adopting partial adjustment of composition of the fresh gas instead of full adjustment to satisfy the H2/CO for both methanol synthesis and SNG synthesis, and thus avoiding greater exergy destruction for individual adjustment of composition of fresh gas in single production systems; (2) Instead of total recycle of the unreacted gas in methanol synthesis unit, partial-recycle scheme is adopted in the polygeneration system, avoiding the sharp increase of energy consumption for methanol synthesis, and at the same time realizing the SNG synthesis with no adjustment of the composition and efficient power generation; (3) recovery of the sensible heat of the syngas and recovery of gases released in chemical synthesis process for power. 2.3. Description of the reference systems For performance comparison, a system of integrated gasification combined cycle (IGCC) for power generation is selected as a reference for the application of power generation. A coal-based methanol production process which adopts the low-pressure Lurgi methanol synthesis technology is selected as the reference for single methanol production system. And a coal-based SNG synthesis process, in which High <strong>Press</strong>ure SNG synthesis technology is applied, is selected as the reference system for SNG production. Figure 5(a) shows the flowsheet of IGCC system, including the air separation unit (ASU), a Texaco slurry-feed and O2-blown gasification unit, clean up unit adopting Selexol process to remove sulfids, and a combined cycle unit. Figure 5(b) shows the flow sheet of single methanol product process, which can be identified into fresh gas preparation subsystem and methanol synthesis subsystem. An ASU unit, a Texaco gasifier, and a cleanup unit are included in fresh gas preparation unit. The composition adjustment unit for producing fresh gas with proper CO/H2, which can meet the synthesis of methanol, is also included in fresh gas preparation subsystem. The methanol synthesis subsystem includes the synthesis unit and distillation unit. In methanol synthesis unit, nearly all of the unreacted gas is sent back to the reactor to pursue highest conversion of materials. In the distillation unit, the crude methanol will be refined as the final product. The steam and work requirements in single methanol product process are supplied by a captive power plant with coal-fired boiler, and by recovering the surplus heat of the chemical reaction. The single SNG product process is shown in Figure 5(c), which can also be divided into fresh gas preparation subsystem and SNG synthesis subsystem. Different from the single methanol process, in the cleanup unit CO2 and sulfids will be removed by low-temperature methanol wash method. In SNG synthesis unit, three sequential reactors adopting TREMP process designed by Haldor Topsoe are placed, in which synthesis reaction occurs at about 80bar, above 300. Between reactors, steam with high parameters, usually 120bar, 535, will be generated to recover heat from the products in case the catalyst was burnt. The superheated steam will supply the work requirement of the single SNG product process, the insufficient of which will be provided by a captive power plant with coalfired boiler if necessary. 5
(a) (b) (c) Fig. 5. Flow diagrams of single product systems: (a) IGCC system (b) single methanol product process (c) single SNG product process 3. PERMORMANCE ANALYSIS OF THE NEW SYSTEM For evaluating the performance improvement of the polygeneration system, a criterion of Energy Saving Ratio (ESR) is defined as follows: [ P/ CGmthCmth GSNG CSNG ] F ESR P/ G C G C C mth mth SNG SNG where P represents the net power output of the polygeneration system, kW; C represents the thermal efficiency of the power reference system (IGCC); G represents the mass flow rate (kg/s); C represents the energy consumption for unit methanol production in a single methanol mth production process, kJ/kg; C mth is the energy consumption for unit SNG production in a single SNG production process, kJ/kg; F represents the lower heating value (LHV) of total fuel input for the polygeneration system, kW. The ESR denotes that how much fossil fuel will be saved if the same products are produced in the polygeneration system as that in the reference systems. The thermal efficiency and exergy efficiency are defined in formula (2) and (3). [ PEmth ESNG ] ESR F where Emth and ESNG represents the energy output of methanol and SNG respectively, kW. 6 (1) (2)
Page 1: Proceedings e report 90
Page 4 and 5: ECOS 2012 : the 25 th International
Page 7 and 8: Advisory Committee (Track Organizer
Page 10 and 11: The 25 th ECOS Conference 1987-2012
Page 12 and 13: VOLUME VI CONTENT VI. 1 CARBON CAPT
Page 14 and 15: -----------------------------------
Page 16 and 17: » Personal transportation energy c
Page 18 and 19: » Excess enthalpies of second gene
Page 20 and 21: VOLUME IV IV . 1 - FLUID DYNAMICS A
Page 22 and 23: » Exergy analysis and genetic algo
Page 24 and 25: » Optimal lighting control strateg
Page 26 and 27: » Stability and limit cycles in an
Page 28 and 29: PROCEEDINGS OF ECOS 2012 - THE 25 T
Page 30 and 31: Fig. 2. The exergy destruction of M
Page 34 and 35: [ P EXmth EX SNG] ESR F where EXm
Page 36 and 37: Fuel inputkW 728221 203771 237719 3
Page 38 and 39: Not only at desined Rc (the ratio o
Page 40 and 41: 4. DISCUSSION The graphic exergy an
Page 42 and 43: Figure 9(a) illustrates the energy
Page 44 and 45: Engineering Technical Conferences &
Page 46 and 47: generally there are four kinds of m
Page 48 and 49: However, even under the off-design
Page 50 and 51: Fig. 3. 600MW supercritical coal-fi
Page 52 and 53: CO2 rich loading(molCO2/molMEA) 0.4
Page 54 and 55: Net efficiency (%) 40.28 30.29 26.4
Page 56 and 57: Fig. 11. Schematic diagram of heat
Page 58 and 59: 28.67%. In addition, through heat i
Page 60 and 61: Applied Thermal Engineering 2010;30
Page 62 and 63: Abstract: PROCEEDINGS OF ECOS 2012
Page 64 and 65: Fig. 1. Solution diagram of „four
Page 66 and 67: K ~ K 1 eK 1a p K 1a iK mK
Page 68 and 69: Oxygen recovery rate, % 105 95 85 7
Page 70 and 71: Calculated optimal compressor press
Page 72 and 73: PROCEEDINGS OF ECOS 2012 - THE 25 T
Page 74 and 75: The net amount of the flue gas leav
Page 76 and 77: Figure 3. Idea for lignite drying b
Page 78 and 79: Energy efficiency, % 34,00 33,00 32
Page 80 and 81: points efficiency increase related
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Figure A1b. Thermoflex flow sheet o
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Figure A3a. Thermoflex flow sheet o
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Figure A4. Thermoflex flow sheet of
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Abstract: PROCEEDINGS OF ECOS 2012
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2.1. Life Cycle Assessment 2.1.1. G
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these factors. A sensitivity analys
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methane slip contributes to 13% of
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As can be seen in Fig. 5 the impact
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References [1] Eurobserv’er, The
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PROCEEDINGS OF ECOS 2012 - THE 25 T
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in which CO2 is separated from H2,
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dimensions of water droplets and wa
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Temperature (°C) 8 7 6 5 4 3 2 1 0
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4. Conclusions In the present paper
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penalty, but without separate captu
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0.5 - 0.7 kg/kg, resulting typicall
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3.3 - Utilising waste heat All exis
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4.5 - Suomusjärvi olivine deposits
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material will change from a few % t
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Fig. 5 Schematic diagram of the PFB
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8. Combined SO2 capture and CO2 min
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Fig. 10 Carbonate- (left) and sulph
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[13] Ekdahl, E., Idman, H. Statemen
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HEAT Fig. 1. Scheme and main reacti
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(raw) materials pre-heating and AS
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Fig 3- Aspen Plus® model 110
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Table 4. Elemental and XRD analysis
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the ÅA CSM route. The content of M
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moisture - 0,2237 ash - 0,0876 LHV
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2.2 CFB plant For the current momen
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The CO2 emission factor which indic
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The CO2 emission factor calculated
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Appendix A Fig A.1. Simulation mode
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(b) Fig. A.2. Simulation model of C
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Table A.1. Calculated parameters at
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References [1] Pfaff I., Oexmann J.
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with a CC installation could be avo
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2.3. Basic CHP plant indices. The b
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3. Off-design calculations The main
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Fig. 6. CHP plant efficiency Fig. 7
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amount of steam delivered to the he
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[5] Lukowicz H., Mroncz M.: Analysi
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water removal is feasible by coolin
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Figure 2. Sketch of the suggested P
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a b Figure 5. a) Exergy balance of
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The basis of comparison of each met
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Figure 7a. Impact of S/CATR on PCU
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However, more energy duty is requir
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3.1. JACOBIAN-ASPEN Interface ASPEN
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Fig. 3. Triple Pressure Bottoming S
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As seen from Table 1, the mass flow
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4. Conclusion Fig. 5. Partial Emiss
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[19] Yantovski E., Shokotov M., Sho
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investigation and the developing of
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University of L’Aquila and German
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hydrogen combustion technology at d
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eversibility of a pre-treated synth
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Fig. 1. TG curves collected for spe
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(see Fig 5). Carbon dioxide uptake
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period is reduced to the first 15 c
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CO2 capture capacity up to 150 th c
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the way for biogas utilisation is t
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projectand is described in the foll
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4. Pilot plant tests In order to de
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Concerning the absorption reaction,
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with Regeneration (AwR), consists i
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[25] Aspen Plus 2004.1. Cambridge,
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systems for fuel drying waste strea
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heated in a heat exchanger placed i
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Fig. 2. Lower heating value of fuel
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Acknowledgements The results presen
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large amount of CO2 [1,5-7]. APCr a
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N 1 i ( x x i n 1 m ) 2.3. Carbon
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DTA analysis of the untreated APCrs
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Table 4. Relative Error (%) of the
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CaO HCl CaCl H O 193kJ / mol (
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[1] M. Fernández Bertos, S.J.R. Si
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2. Process development 2.1. Backgro
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to dissolve the chloride salts prec
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The remaining 25% (5 ml/min) of the
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Table 6. Experimental conversions o
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p p 1 1. 5 p H 1 1. 5 2O p mi
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Calculating from the Aspen Plus mod
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[11] Mattila, H.-P., Experimental s
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Mg2SiO4(s) + 2CO2(g) →2MgCO3(s) +
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(Mg/Fe) of the mineral rock, Mg-sil
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Figure 2. Effect of Mg/Fe ratio of
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Figure 4 shows that an increase in
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Figure 5. Process flow diagram of M
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2. Only cold utility is needed belo
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extraction process at 400 °C (~ 62
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Table A2. Extraction equations and
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[13] Teir S, Kuusik R, Fogelholm CJ
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In the area of coal technologies al
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Tabel 1. Characteristics quantities
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N m eT 4a ~ T cp T4a 1 ( K
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Auxiliary power rate of ASU, % 40 4
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[8] Buhre B.J.P., Elliott L.K., She
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1.1 - Cement Manufacturing The ceme
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2. Numerical model The purpose of t
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-0.309x15.77x2 2.085x3 240x4 12.53x
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Table 4 - Results of the optimizati
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1. Define the studied system (in th
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cycle) or a lignin extraction plant
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limiting factor for the maximum siz
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Table 5. Key data for the four ener
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Global CO 2 emissions [ktonnes/yr]
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for biofuels and the investment cos
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The possibility to capture CO2 from
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[17] Berglin N, Andersson L. Proces
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Therefore NL Agency (an agency of t
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2.2.2. Pinch analysis Pinch analysi
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3. Case study 3.1. Plant and proces
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Te 1000 mp era 900 tur 800 e [°C 7
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Application of the approach led to
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The advantage of dynamic models is
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e equal at both time intervals and
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2.5. Selecting the number of TSs Se
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A) Time Slices for solar thermal en
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The first step of procedure is to p
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cTSs demand TS solar TSs 0 2 4 6 8
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In the presented paper a framework
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[5] Erdil E, Ilkan M, Egelioglu F.
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district energy network simulation
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were decreased by 10°C.All scenari
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Site 3 Heat sources Heat load Site
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3.2.2. Input data and assumptions A
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Fig.7 shows the operation forecast
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[13] TERMIS Operation User Guide, 7
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Polygeneration is a term used to de
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The increase in energy utilization
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are available for an entire year, 8
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6. Extensions to core methodology 6
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thermal storage and possible suppor
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laterites. Ore Geology Reviews, v.
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gasification [15], hybrid biomass g
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the second reactor. In this unit, s
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The variables effect was evaluated
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atio, as well as the shift-syngas f
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Fig. 4. Effect of operating tempera
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SDG has slight effect on the syngas
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[26.] Castle WF. Air separation and
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1. Introduction - Firenze University Press

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