Industrial Fixed-Bed Coal Gasification: An Economic Alternative to Deregulated Natural Gas

1981 ◽  
Author(s):  
Rolf E. Maurer
Author(s):  
Radwa A. El-Salamony ◽  
Sara A. El-Sharaky ◽  
Seham A. Al-Temtamy ◽  
Ahmed M. Al-Sabagh ◽  
Hamada M. Killa

Abstract Recently, because of the increasing demand for natural gas and the reduction of greenhouse gases, interests have focused on producing synthetic natural gas (SNG), which is suggested as an important future energy carrier. Hydrogenation of CO2, the so-called methanation reaction, is a suitable technique for the fixation of CO2. Nickel supported on yttrium oxide and promoted with cobalt were prepared by the wet-impregnation method respectively and characterized using SBET, XRD, FTIR, XPS, TPR, and HRTEM/EDX. CO2 hydrogenation over the Ni/Y2O3 catalyst was examined and compared with Co–Ni/Y2O3 catalysts, Co% = 10 and 15 wt/wt. The catalytic test was conducted with the use of a fixed-bed reactor under atmospheric pressure. The catalytic performance temperature was 350 °C with a supply of H2:CO2 molar ratio of 4 and a total flow rate of 200 mL/min. The CH4 yield was reached 67%, and CO2 conversion extended 48.5% with CO traces over 10Co–Ni/Y2O3 catalyst. This encourages the direct methanation reaction mechanism. However, the reaction mechanism over Ni/Y2O3 catalyst shows different behaviors rather than that over bi-metal catalysts, whereas the steam reforming of methane reaction was arisen associated with methane consumption besides increase in H2 and CO formation; at the same temperature reaction.


2000 ◽  
Author(s):  
Hongguang Jin ◽  
Masaru Ishida

Abstract A new type of integrated gasification combined cycle (IGCC) with chemical-looping combustion and saturation for air is proposed and investigated. Chemical-looping combustion may be carried out in two successive reactions between two reactors, a reduction reactor (coal gas with metal oxides) and an oxidation reactor (the reduced metal with oxygen in air). The study on the new system has revealed that the thermal efficiency of this new-generation power plant will be increased by approximately 10–15 percentage points compared to the conventional IGCC with CO2 recovery. Furthermore, to develop the chemical-looping combustor, we have experimentally examined the kinetic behavior between solid looping materials and coal gas in a high-pressure fixed bed reactor. We have identified that the coal gas chemical-looping combustor has much better reactivity, compared to the natural gas one. This finding is completely different from the direct combustion in which combustion with natural gas is much easier than that with other fuels. Hence, this new type of coal gas combustion will make breakthrough in clean coal technology by simultaneously resolving energy and environment problems.


2021 ◽  
Vol 61 (2) ◽  
pp. 325
Author(s):  
Barry E. Bradshaw ◽  
Meredith L. Orr ◽  
Tom Bernecker

Australia is endowed with abundant, high-quality energy commodity resources, which provide reliable energy for domestic use and underpin our status as a major global energy provider. Australia has the world’s largest economic uranium resources, the third largest coal resources and substantial conventional and unconventional natural gas resources. Since 2015, Australia’s gas production has grown rapidly. This growth has been driven by a series of new liquefied natural gas (LNG) projects on the North West Shelf, together with established coal seam gas projects in Queensland. Results from Geoscience Australia’s 2021 edition of Australia’s energy commodity resources assessment highlight Australia’s endowment with abundant and widely distributed energy commodity resources. Knowledge of Australia’s existing and untapped energy resource potential provides industry and policy makers with a trusted source of data to compare and understand the value of these key energy commodities to domestic and world markets. A key component of Australia’s low emissions future will be the development of a hydrogen industry, with hydrogen being produced either through electrolysis of water using renewable energy resources (‘green’ hydrogen), or manufactured from natural gas or coal gasification, with carbon capture and storage of the co-produced carbon dioxide (‘blue’ hydrogen). Australia’s endowment with abundant natural gas resources will be a key enabler for our transition to a low emissions future through providing economically competitive feedstock for ‘blue’ hydrogen.


Energies ◽  
2020 ◽  
Vol 13 (11) ◽  
pp. 2844 ◽  
Author(s):  
Panagiota Garbis ◽  
Andreas Jess

Polymer electrolyte membrane fuel cells (PEMFCs) are often used for household applications, utilizing hydrogen produced from natural gas from the gas grid. The hydrogen is thereby produced by steam reforming of natural gas followed by a water gas shift (WGS) unit. The H2-rich gas contains besides CO2 small amounts of CO, which deactivates the catalyst used in the PEMFCs. Preferential oxidation has so far been a reliable process to reduce this concentration but valuable H2 is also partly converted. Selective CO methanation considered as an attractive alternative. However, CO2 methanation consuming the valuable H2 has to be minimized. The modelling of selective CO methanation in a household fuel cell system is presented. The simulation was conducted for single and two-stage adiabatic fixed bed reactors (in the latter case with intermediate cooling), and the best operating conditions to achieve the required residual CO content (100 ppm) were calculated. This was done by varying the gas inlet temperature as well as the mass of the catalyst. The feed gas represented a reformate gas downstream of a typical WGS reaction unit (0.5%–1% CO, 10%–25% CO2, and 5%–20% H2O (rest H2)).


2020 ◽  
Vol 7 (3) ◽  
pp. 516-535
Author(s):  
Tamer M. Ismail ◽  
Mingliang Shi ◽  
Jianliang Xu ◽  
Xueli Chen ◽  
Fuchen Wang ◽  
...  

Abstract With the help of Aspen Plus, a two-dimensional unsteady CFD model is developed to simulate the coal gasification process in a fixed bed gasifier. A developed and validated two dimensional CFD model for coal gasification has been used to predict and assess the viability of the syngas generation from coal gasification employing the updraft fixed bed gasifier. The process rate model and the sub-model of gas generation are determined. The particle size variation and char burning during gasification are also taken into account. In order to verify the model and increase the understanding of gasification characteristics, a set of experiments and numerical comparisons have been carried out. The simulated results in the bed are used to predict the composition of syngas and the conversion of carbon. The model proposed in this paper is a promising tool for simulating the coal gasification process in a fixed bed gasifier.


1986 ◽  
Vol 108 (2) ◽  
pp. 131-139 ◽  
Author(s):  
K. Vafai

A theoretical solution of the channeling effect is presented. The details of the channeling production are investigated in detail and an approximate method for obtaining the temperature distribution is presented. These results complete a theoretical solution of the channeling effect which has a number of different applications in energy-related problems, such as fixed-bed catalytic reactors, metal processing, underground coal gasification, oil shale, chemical-reaction engineering, drying and packed-bed heat exchangers. These differential permeability problems are also encountered in several energy resource extraction applications related to underground coal conversion, vertical modified in-situ (VSIS) oil shale retortion, steam flooding and oil recovery from tar sands. The method of matched asymptotic expansions is used to obtain the theoretical solution. The effects of using the singular perturbation solution in obtaining the temperature distribution are discussed. The existence and the concept of the triple momentum boundary layer in variable porosity media is analyzed in detail. The theoretical results are found to be in good agreement with the numerical and the available experimental results.


Sign in / Sign up

Export Citation Format

Share Document