Published September 2013
In regions with limited access to low-cost natural gas, coal gasification is becoming an important route to the manufacture of synthesis gas. Coal gasification technologies have advanced significantly in recent years, in terms of feed handling capacity and efficiency, particularly with the development of entrained-flow gasifiers. Coal gasification has been based, for the most part, on bituminous coals. Gasification of lower rank coals has been limited. However, the nature of the coal market and the abundance of lower grade coals naturally foster an interest in the use of lower grade coals such as subbituminous coal and lignite. In addition, refineries around the world are producing a large stockpile of petroleum coke that can be gasified to produce synthesis gas. Petroleum coke, limited by proximity to refineries, is an opportunity feedstock, which can sometimes be a lower cost fuel.
This report will present syngas processes and economics modules for the utilization of the following solid feedstocks:
- Bituminous coal
- Subbituminous coal
- Lignite
- Petroleum coke
The solid feedstocks are converted to synthesis gas via oxygen-blown entrained-flow gasifiers. The gasification technologies covered in this report include the following:
- GE Energy quench gasifier
- GE Energy radiant gasifier
- Shell Coal Gasification Process (SCGP) gasifier
- E-Gas™ gasifier (CB&I, formerly ConocoPhillips)
- Siemens Fuel Gasifier (SFG)
The report is accompanied by a Microsoft Excel workbook (PEPSyngas™) containing syngas modules from gasification of coal and petroleum coke (PEP Report 148C) and natural gas reforming (PEP Report 148B) available to PEP clients. The workbook module contains a user interface (written by the author in Visual Basic for Applications 7.0). The output in each module will consist of stream flow, mass, energy balance, production costs, and capital costs for any combination of feedstock and gasification technology to produce synthesis gas of essentially any H2/CO molar ratio at the capacity and operating conditions specified. This modular approach allows for immediate implementation of the syngas economics output of any module for downstream product needs, which can be used for assessing the competitiveness of new projects. The report also includes background technical information on the various feedstocks, gasifier technologies, and end-use applications of synthesis gas.