Enhanced sorption biomass gasification for hydrogen and biomethane production

Žalec, Domen (author), Golobič, Iztok (mentor)

This work deals with development of a conceptual process system for enhanced sorption biomass (BM) gasification. Aspen Plus® process simulation tool was used to develop an adjustable process model for production of either hydrogen or biomethane. This was achieved by integration of calcium looping process with gasification process into a single system for in-situ CO2 removal. The process is based on steam blown dual fluidised bed reactor, operating at low pressures and low-medium temperatures. By control of process’ operating parameters the produced syngas was optimised for maximum H2 content or for stoichiometric H2/CO2 ratio for downstream Sabatier methanation process. Simulations were performed and a parametric study was conducted to assess the system’s performance. H2 production yielded syngas with up to 96,8 mol. % H2 content and overall process efficiency of 67,3 %LHV. Biomethane production achieved up to 95,3 mol. % CH4 content with 79,0 %LHV process efficiency. 0,112 kg H2/kg BM and 0,23 kg CH4/kg BM product yields were recorded for hydrogen and biomethane production, respectively. The proposed process designs were found to be on par or superior to experimental and pilot plant results available from the literature. Moreover, a few extra percent points in efficiency increase were found to be possible during the sensitivity analysis. The proposed sorption enhanced concept for biomass gasification provides gaseous fuels with low-sulphur content and negative carbon footprint. The main advantage of the proposed system, compared to alternative process designs, is ability to operate in two modes for different product gases.

• Language: English
• Keywords: sorption enhanced gasification, calcium looping, process efficiency, renewable energy, hydrogen, biomethane, biomass, Aspen Plus®
• Work type: Master's thesis/paper
• Typology: 2.09 - Master's Thesis
• Organization: FS - Faculty of Mechanical Engineering
• Place of publishing: Ljubljana
• Publisher: [D. Žalec]
• Year: 2019
• Number of pages: XXI, 82 str.
• PID: 20.500.12556/RUL-109264
• UDC: 662.63:620.92(043.2)
• COBISS.SI-ID: 16866075
• Publication date in RUL: 29.08.2019

ŽALEC, Domen, 2019, Enhanced sorption biomass gasification for hydrogen and biomethane production [online]. Master’s thesis. Ljubljana : D. Žalec. [Accessed 31 May 2025]. Retrieved from: https://repozitorij.uni-lj.si/IzpisGradiva.php?lang=eng&id=109264

Secondary language

• Language: Slovenian
• Title: Izboljšano sorpcijsko uplinjanje biomase za proizvodnjo vodika in biometana

Abstract

To delo obravnava razvoj konceptnega procesnega sistema za izboljšano sorpcijsko uplinjanje biomase. S simulacijskim orodjem Aspen Plus® je bil razvit prilagodljiv model procesa uplinjanja za proizvodnjo vodika in biometana. To je bilo doseženo z integracijo procesa kalcijeve zanke in procesa uplinjanja v enotnen sistem za sprotni zajem CO2. Proces je osnovan na dvojnem reaktorju s fluidiziranim slojem in se vrši pri nizih tlakih in nizkih do srednjih temperaturah. S kontrolo procesnih parametrov je bila sestava sinteznega plina optimizirana za maksimalni delež H2 ali za stohiometrično razmerje H2/CO2, potrebno za Sabatierjev proces metanizacije. Zmogljivost obravnavanih procesov je bila ovrednotena na osnovi simulacij in analize občutljivosti. Pri nastavitvi procesa za proizvodnjo vodika je bil pridelan sintezni plin z 96,8 mol. % H2 in učinkovitostjo procesa 67,3 %LHV. Pri proizvodnji biometana je bil pridelan sintezni plin z 95,3 mol. % CH4 in učinkovitostjo 79,0 %LHV. Iz enega kilograma biomase je bilo pridobljenega 0,012 kg vodika oz. 0,23 kg biometana. Zmogljivost predlaganih procesov se je izkazala za primerljivo ali višjo v primerjavi z rezultati eksperimentalnih in pilotnih projektov iz literature. Prav tako je bilo med analizo občutljivosti odkritih nekaj možnih izboljšav za povišanje učinkovitosti procesov. Predlagani koncept za sorpcijsko izboljšano uplinjanje biomase omogoča pridelavo plinastih goriv z nizko vsebnostjo žvepla in negativnim ogljičnim odtisom. Glavna prednost pred alternativni procesi je zmožnost obratovanja v dveh načinih za proizvodnjo različnih plinov.

• Keywords: sorpcijsko izboljšano uplinjanje, kalcijeva zanka, učinkovitost procesa, obnovljivi viri energije, vodik, biometan, biomasa, Aspen Plus®