Hydrogen Production From Ethanol: A Thermodynamic Analysis of a Novel Sorbent Enhanced Gasification Process

2005 ◽  
Author(s):  
Madhukar R. Mahishi ◽  
Mojtaba S. Sadrameli ◽  
Sanjay Vijayaraghavan ◽  
Dharendra Y. Goswami
Keyword(s):  
Hydrogen Production ◽  
Product Yield ◽  
Hydrogen Yield ◽  
Gas Composition ◽  
Equilibrium Modeling ◽  
Gasification Process ◽  
Product Gas ◽  
Co2 Sorbent ◽  
Effects Of Temperature ◽  
Minimization Approach

A novel biomass hydrogen production technique by integrating gasification and absorption reactions has been suggested. The method involves gasification of biomass in presence of a CO2 sorbent. Ethanol was used as the model biomass compound and CaO was the representative sorbent. Equilibrium modeling was used to determine the product gas composition and hydrogen yield. The analysis was done using ASPEN PLUS software (version 12.1) and Gibbs energy minimization approach was followed. The effects of temperature, pressure, steam/ethanol ratio and CaO/ethanol ratio on product yield were investigated. Three case studies were conducted to understand the effect of sorbent addition on hydrogen yield. Finally a simple energy analysis was carried out to determine the energy consumption and efficiency of sorbent enhanced ethanol gasification.

A Novel Approach to Enhance the Hydrogen Yield of Biomass Gasification Using CO2 Sorbent

2007 ◽  
Vol 130 (1) ◽  
Author(s):  
Madhukar R. Mahishi ◽  
M. S. Sadrameli ◽  
Sanjay Vijayaraghavan ◽  
D. Y. Goswami
Keyword(s):  
Product Yield ◽  
Biomass Gasification ◽  
Thermodynamic Efficiency ◽  
Hydrogen Yield ◽  
Equilibrium Constraints ◽  
Novel Approach ◽  
Product Gas ◽  
Co2 Sorbent ◽  
Effects Of Temperature ◽  
The Cost

Hydrogen yield of conventional biomass gasification is limited by chemical equilibrium constraints. A novel technique that has the potential to enhance the hydrogen yield by integrating the gasification and absorption reactions has been suggested. The method involves gasification of biomass in presence of a CO2 sorbent. Ethanol was used as the model biomass compound and CaO was the representative sorbent. Equilibrium modeling was used to determine the product gas composition and hydrogen yield. The analysis was done using ASPEN PLUS software (version 12.1) and the Gibbs energy minimization approach was followed. The effects of temperature, pressure, steam/ethanol ratio, and CaO/ethanol ratio on product yield were investigated. Three case studies were conducted to understand the effect of sorbent addition on the hydrogen yield. Thermodynamic studies showed that the use of sorbents has the potential to enhance the equilibrium hydrogen yield of conventional gasification by ∼19% and reduce the equilibrium CO2 content of product gas by 50.2%. It was also found that the thermodynamic efficiency of sorbent-enhanced gasification (72.1%) was higher than conventional gasification (62.9%). Sorbent-enhanced gasification is a promising technology with a potential to improve the yield and lower the cost of hydrogen production.

scholarly journals Catalytic gasification of oil palm empty fruit bunch by using Indonesian bentonite as the catalyst

2021 ◽  
pp. 1-10
Author(s):  
Nabila Aprianti ◽  
Muhammad Faizal ◽  
Muhammad Said ◽  
Subriyer Nasir
Keyword(s):  
Oil Palm ◽  
Empty Fruit Bunch ◽  
Gas Composition ◽  
Catalytic Gasification ◽  
Heating Value ◽  
Gasification Process ◽  
Cold Gas Efficiency ◽  
Product Gas ◽  
Effects Of Temperature ◽  
Gas Efficiency

Oil palm empty fruit bunch (OPEFB is one of the enormous waste expected to become a renewable energy source. This study aimed to convert OPEFB into syngas through a gasification process using bentonite as a catalyst. The effects of temperature and product gas catalysts were investigated, and the efficiency of the gasification process was summarized. The process has used an updraft gasifier at 350-550 °C and air as the gasification medium (ER 0.2). The results indicate that syngas can be produced by updraft gasifier. When the temperature increase, the H2 and CO rising. The highest H2 and CO content of 27.74% and 20.43% are obtained at 550°C when bentonite applied. HHV and LHV range of 3.38~12.79 MJ/Nm3 and 3.03~11.58 MJ/Nm3, respectively. The maximum carbon conversion efficiency (CCE) and cold gas efficiency (CGE) reach 85.49% and 82.34%. Bentonite has been able to increase the concentration of the gas composition especially H2 and CO and the heating value of syngas.

Characteristics of "Three Zones" during Underground Coal Gasification

2012 ◽  
Vol 524-527 ◽  
pp. 56-62 ◽  
Author(s):  
Hong Tao Liu ◽  
Hong Yao ◽  
Kai Yao ◽  
Feng Chen ◽  
Guang Qian Luo
Keyword(s):  
Large Scale ◽  
Coal Gasification ◽  
Basic Knowledge ◽  
Gas Composition ◽  
Underground Coal Gasification ◽  
Reduction Zone ◽  
Gasification Process ◽  
Product Gas ◽  
Dry Distillation ◽  
Major Chemical

According to the temperature, major chemical reactions and gas compositions, the gasification process along the tunnel of underground coal gasification is divided into three zones, i.e. oxidation zone, reduction zone and dry distillation zone. A model test in the laboratory was carried out by using large-scale coal blocks to simulate the coal seam. The characteristics of the “three zones”, and the relation between the temperature and gas composition were also quantitative studied. It provided the necessary basic knowledge for further studying the process of underground coal gasification, including predicting compositions of product gas, life-cycle analyzing, selecting optimistic control parameters and determining suitable gasification craft.

Hydrogen production from wastewater by acidogenic granular sludge

2003 ◽  
Vol 47 (1) ◽  
pp. 153-158 ◽  
Author(s):  
H. Liu ◽  
H.H.P. Fang
Keyword(s):  
Hydrogen Production ◽  
Carbon Balance ◽  
Volatile Fatty Acids ◽  
Sucrose Concentration ◽  
Maximum Yield ◽  
Granular Sludge ◽  
Hydrogen Yield ◽  
Gas Composition ◽  
Acidogenic Reactor ◽  
Constant Loading Rate

Sludge was granulated in a hydrogen-producing acidogenic reactor when operated at 26°C, pH 5.5 treating a sucrose-rich wastewater. The influence of hydraulic retention time (HRT) and sucrose concentration on hydrogen production by the acidogenic granular sludge was investigated at a constant loading rate of 25 g-sucrose/(láday). Results show that the gas composition was not greatly influenced by HRT or sucrose concentration. The hydrogen accounted for 57% to 68% of the biogas at HRT ranging 4.6-28.6 h and sucrose concentration ranging 4,800-29,800 mg/l. However, the hydrogen yield was more dependent on HRT and sucrose concentration. It ranged from 0.19 to 0.27 l/g-sucrose with the maximum yield occurring at HRT 13.7 h and sucrose concentration 14,300 mg/l in the wastewater. The acidified effluent was composed of volatile fatty acids and alcohols. The predominant products were butyrate (59-68%) and acetate (10-25%), plus smaller amounts of i-butyrate, valerate, i-valerate, caproate, methanol, ethanol, propanol, and butanol. The sludge yield averaged 0.2 g-VSS/g-sucrose. The carbon balance was 98-107% throughout the study.

Steam Reforming of Acetic Acid for Hydrogen Production: Thermodynamic Calculations

2012 ◽  
Vol 534 ◽  
pp. 141-145 ◽  
Author(s):  
Long Guo ◽  
Xin Bao Li ◽  
Qi Wang ◽  
Shu Rong Wang
Keyword(s):  
Acetic Acid ◽  
Hydrogen Production ◽  
Steam Reforming ◽  
Thermodynamic Calculation ◽  
Model Compound ◽  
Thermodynamic Calculations ◽  
Product Gas ◽  
Bio Oil ◽  
Effects Of Temperature ◽  
H2 Yield

In our work, acetic acid was used as a bio-oil model compound. Thermodynamic calculation of hydrogen production via steam reforming of acetic acid was attempted to investigate the effects of temperature (200-1100 °C), pressure（1-19 atm ）and steam to carbon ratio (1.5-10.5) on the concentration of equilibrium product gas and H2 yield. The results show that temperature has a profound effect on the steam reforming of acetic acid. Lower pressure and higher steam to carbon ratio are in favor of higher hydrogen production.

AN OVERVIEW OF HYDROGEN FUEL FROM BIOMASS GASIFICATION - COST EFFECTIVE ENERGY FOR DEVELOPING ECONOMY

2021 ◽  
Vol 36 (1) ◽  
pp. 42-52
Author(s):  
F. N Osuolale ◽  
K. A. Babatunde ◽  
O.O Agbede ◽  
A. F Olawuni ◽  
A.J Fatukasi ◽  
...  
Keyword(s):  
Hydrogen Production ◽  
Cost Effective ◽  
Biomass Gasification ◽  
Operating Conditions ◽  
Thermochemical Conversion ◽  
Gasification Process ◽  
Product Gas ◽  
Economic Process ◽  
Percentage Yield ◽  
Different Sources

Hydrogen has the potential to be a clean and sustainable alternative to fossil fuel especially if it is produced from renewable sources such as biomass. Gasification is the thermochemical conversion of biomass to a mixture of gases including hydrogen. The percentage yield of each constituent of the mixture is a function of some factors. This article highlights various parameters such as operating conditions; gasifier type; biomass type and composition; and gasification agents that influence the yield of hydrogen in the product gas. Economic evaluation of hydrogen from different sources was also presented. The hydrogen production from gasification process appears to be the most economic process amongst other hydrogen production processes considered. The process has the potential to be developed as an alternative to the conventional hydrogen production process.

Steam Reforming of Model Compounds from Bio-Oil for Hydrogen Production over Pd/HZSM-5 Catalyst

2012 ◽  
Vol 550-553 ◽  
pp. 558-562
Author(s):  
Qi Wang ◽  
Long Guo ◽  
Xin Bao Li
Keyword(s):  
Hydrogen Production ◽  
Steam Reforming ◽  
Fixed Bed ◽  
Fixed Bed Reactor ◽  
Hydrogen Yield ◽  
Impregnation Method ◽  
Wet Impregnation ◽  
Product Gas ◽  
Bio Oil ◽  
H2 Yield

Ethanol was selected as a model compound of bio-oil. Pd/HZSM-5 catalyst with 5%wt Pd was prepared by wet impregnation method. The steam reforming experiment for hydrogen production was carried out on a fixed bed reactor. The carbon conversion, carbon selectivity of product gas and H2 yield was calculated according the experimental resultsl. It has been found that the best performance was obtained at T=700°C, S/C=9.2 and GC1HSV=346h-1. At this condition, the hydrogen yield and potential hydrogen yield can be as high as 58.1% and 84.3%. The results show that the addition of Pd to HZSM-5 can improve the reforming performance and increase the hydrogen yield.

Simulation of Chemical Looping Hydrogen Production Using Solid Fuel

2013 ◽  
Vol 724-725 ◽  
pp. 1254-1257 ◽  
Author(s):  
Long Fei Wang ◽  
Shu Zhong Wang ◽  
Ming Luo
Keyword(s):  
Hydrogen Production ◽  
Solid Fuel ◽  
Flue Gas ◽  
Carbon Capture ◽  
Oxygen Carrier ◽  
Chemical Looping ◽  
Gas Composition ◽  
Reactor Performance ◽  
Simulation Results ◽  
Effects Of Temperature

Chemical looping hydrogen production (CLH) has become a promising technology for hydrogen production with inherent separation of carbon dioxide. This paper simulated the three reactors of CLH process of coal as solid fuel using Aspen Plus. The effects of temperature, oxygen carrier/coal ratio, steam/coal ratio, and the air/coal ratio on the gas composition in specific reactor were discussed. Simulation results showed that the temperature had a great effect on the reactor performance. The optimized OC/coal ratio in the OC/coal ratio in this paper was 19.1. The CO2 fraction in the flue gas of FR reached 87.5% when the vapor was condensed at the temperature of 950 °C. The fraction of dry-based H2 in the SR was almost 100% when the SR temperature was 815 °C and the steam/coal ratio was 18.8. The simulation confirmed that the CLH process showed high potential in hydrogen production and the carbon capture.

Technical and Economic Evaluation of Hydrogen Production by Biomass Gasification in Supercritical Water and in Air-Steam Media

2014 ◽  
Vol 953-954 ◽  
pp. 267-270
Author(s):  
Sheng Wen ◽  
Shu Zhong Wang ◽  
Yan Hui Li ◽  
Yu Zhen Wang
Keyword(s):  
Hydrogen Production ◽  
Supercritical Water ◽  
Biomass Gasification ◽  
Gas Composition ◽  
Operation Costs ◽  
Operation Process ◽  
Product Gas ◽  
Gasification Efficiency ◽  
The Cost ◽  
Process Product

Technical and economic conditions of hydrogen production by biomass gasification in supercritical water and in air-steam media have been evaluated. Reaction mechanism, technological process, product gas composition and operation costs of two processes were compared. Results indicate that biomass gasification in supercritical water has much more advantages than in air-steam medium, such as easier operation process, smaller machine area, high gasification efficiency, and less pollution, etc. There are no needs of biomass pretreatment and post-processing for product gas in supercritical water. Moreover, the proportions of hydrogen, carbon dioxide, methane are high, so these kinds of product gas all can be utilized. However, the cost of producing 1Nm3hydrogen in supercritical water is $0.6537, which is a little higher than $0.4228 in air-steam media. With the construction of more supercritical water unit and accumulation of more experience, hydrogen production by biomass gasification in supercritical water will have a more bright future.

Environmental and thermodynamic performance assessment of biomass gasification process for hydrogen production in a downdraft gasifier

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Tayebeh Marzoughi ◽  
Fereshteh Samimi ◽  
Mohammad Reza Rahimpour
Keyword(s):  
Hydrogen Production ◽  
Steam Gasification ◽  
Molar Ratio ◽  
Inlet Temperature ◽  
Hydrogen Yield ◽  
Comparative Performance ◽  
Gasification Process ◽  
Thermodynamic Performance ◽  
Biomass Materials ◽  
Gasification Temperature

Abstract Gasification is one of the most efficient techniques for sustainable hydrogen production from biomass. In this study, a comparative performance analysis of the gasification process using various types of biomass materials was undertaken via thermodynamic approach. Air, steam, and air/steam as the traditional gasifying agents were applied to provide an opportunity to choose the most proper agent in the process. This paper also evaluates the environmental impacts of the process in terms of CO2 emission by using Aspen Energy Analyzer. The effects of agent to biomass molar ratio, agent inlet temperature, moisture content of biomass material, and gasification temperature were estimated based on the producer gas compositions, hydrogen yield and heating values. The results indicate that the highest hydrogen yield (0.074 g H2/g biomass) was obtained in the steam gasification of plastic, while air gasification of paper generates the lowest one. It was also observed that manure is the most beneficial from environmental perspectives, while tire and plastic have the highest contribution to CO2 emission and consequently global warming. The higher values of hydrogen production and LHV of produced gas are associated respectively with using steam, air/steam, and air as the gasification agents. The lowest value of CO2 emission is obtained for air, air/steam, and steam as the gasifying agents, respectively.

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