Skip navigation

Category Archives: Gasification

Gasifier to Methanol Plant

 

Wong Ha Ing

 

Bachelor of Engineering Thesis

 

THE UNIVERSITY OF QUEENSLAND

Division of Chemical Engineering

 

Abstract
This project relates to the production of methanol from a gasification coal process at Tarong Power Plant. The gasification process produces syngas (CO + H2) which can be further processed for methanol production. Crude methanol is the initial product which requires further distillation in order to meet the final product specifications as Chemical Grade AA methanol, Fuel Grade Methanol and MTBE Grade Methanol.
Coal is a combustible mineral that contains more than 50% w/w of carbonaceous material. Coal gasification technology is the latest “clean coal technology” whose resulting product gases such as CO2, CO, H2, CH4 and others can be used to produce methanol, low sulphur diesel or hydrogen for fuel cell applications. The technology will also reduce gaseous emissions to the environment, which results in reduction of environmental pollution impact such as the greenhouse effect, acid rain, and photochemical smog.
Gasification is defined as conversion of coal to produce gases such as CO, H2, CH4 and others. The syngas mainly (CO + H2) is fed to a liquid fuel plant to produce low sulphur diesel, methanol or perhaps hydrogen. There are many types of gasifier design such as the entrained flow gasifier, moving bed gasifier, fluidized bed gasifier and fixed bed gasifier. Typically there are two stages of gasification before syngas is produced- pyrolysis and gasification/ combustion. The descriptions of various gasifiers are given in the literature review section. The syngas is fed to cleaning technology units such as particulate matter removal units, water removal units, sulphur removal units and carbon dioxide removal units before being fed to the methanol synthesis unit. 2 main processes take place in the methanol synthesis plant- water gas shift reaction and Low Pressure Methanol process to produce crude methanol before is delivered to purification units for further purification. By- products, especially steam, can be used for power generation application to produce additional electricity.
In addition to the literature review this thesis also consists of a PFD of a methanol synthesis plant and ASPEN simulation model analysis. This is important to ensure the liquid fuel plant operates under a safe and effective regime.

 

Download this paper at :

http://www.cheque.uq.edu.au/ugrad/theses/2004/pdf/CHEE4006/40228994/40228994.pdf

Advertisements

STATUS OF BIOMASS GASIFICATION FOR POWER PRODUCTION

SPLIETHOFF, Hartmut

IFRF – Combustion Journal – 1999 – 2001

ABSTRACT
The most commonly used gasification technologies are fixed bed and fluidized bed gasifiers. Fixed bed gasifiers are employed in the low-capacity range of some MWth, fluidized bed installations, typically in the range above 5 MWth.

The gas produced in the gasifier can be used in various ways for electricity production or for the production of process heat. The systems differ with respect to efficiency, costs, and demand on the gas quality. Engines are suited for electric capacities between ca. 50 kWe and 10 MWe in connection with atmospheric fixed-bed gasifiers. From a capacity of about 5 MWe gas turbines, often in combination with a fluidised bed gasifier, are an alternative. In order to avoid fouling and deposits in the engine, the gas should be to a large degree tar- and dust-free. The requirements for fuel cells are more stringent, however a clear concept about allowed concentrations in the product gas is not yet available.

The gasifiers available on the market today exceed the indicated values by far when operated without gas cleaning. The removal of both tar and particles is therefore a requisite. The use of the product gases for thermal purposes does not make such high demands on the quality regarding tar and dust content. So for those applications it is not necessary to provide for a special gas cleaning.

Link to this paper at : http://www.journal.ifrf.net/library/november2001/200109spliethoff.pdf

OPET Report 4

TECHNICAL RESEARCH CENTRE OF FINLAND. ESPOO 2002.

Link to this paper at : http://www.gastechnology.org/webroot/downloads/en/IEA/OPETReport4gasification.pdf

Gridley Ethanol Demonstration Project Utilizing Biomass Gasification Technology: Pilot Plant Gasifier and Syngas Conversion Testing

August 2002—June 2004

TSS Consultants For the City of Gridley, California Gridley, California

 

PURPOSE OF THE REPORT

This report is in response to Task 3 of the National Renewable Energy Laboratory (NREL) Subcontract No. ZCO-2-32065-01, that describes the Pearson Technologies Pilot Plant Gasifier and Syngas Conversion Testing for converting California rice straw into syngas and then the syngas into ethanol. The report on this task of the NREL Subcontract is part of an overall evaluation of using a modified Pearson Pilot Plant for processing rice straw into syngas and ethanol and the application of the Pearson technology for building a Demonstration Plant at Gridley. The Demonstration Plant would be located in the recently developed City of Gridley Industrial Park in Gridley, California (“Gridley”). This report also includes information on the feedstock preparation, feedstock handling, feedstock performance, catalyst performance, ethanol yields and potential problems identified from the pilot scale experiments.

 

Download this paper at : www.nrel.gov/docs/fy05osti/37581.pdf

Energyplexes for the 21st century: Coal gasification for co-producing hydrogen, electricity and liquid fuels

Kei Yamashita, Leonardo Barretob

Energy 30 (2005) 2453–2473

 

Abstract

This paper illustrates the role that integrated energy systems, also known as ‘energyplexes’, could play in supplying energy demands in the long term. These systems could enable a multi-fuel, multi-product strategy with both economic and environmental benefits. They could increase the adaptability and robustness of energy-services companies in the marketplace, providing them with flexibility in meeting demands in different market segments while achieving lower production costs and, reducing the risks of reliance on a single feedstock. In addition, with the possibility of achieving high conversion efficiencies and low polluting emissions and facilitating carbon capture, they could deliver high-quality energy services in a cost-effective way while meeting stringent
environmental requirements. Their potential is highlighted here using the case of coal-fired, synthesis-gas-based gasification systems that allow co-producing hydrogen, electricity and liquid fuels, i.e. Fischer–Tropsch liquids and methanol, and could be a key building block in a clean-coal technology strategy. Co-production, also known as poly-generation, strategies may contribute to improve the economics of the system and exploit potential synergies between the constituent processes. However, the technical feasibility and economic viability of poly-generation schemes have to be examined carefully on a case-by-case basis.

Download this paper at :

http://www.iiasa.ac.at/Publications/Documents/RP-05-005.pdf