Fixed bed slagging gasifier (BGL)
The principle of a slagging fixed-bed gasifier basing upon the British Gas/Lurgi (BGL) technology is predominantly applied for the generation of high-quality syngas which is free of any attendant substances and can be processed to various products.
The gasifier is operated under a pressure of 30 – 40 bar. Technical oxygen and steam are used as the gasifying medium. Apart from carbon monoxide and hydrogen, the generated syngas contains methane which amounts to 6 - 10 %. With BGL technology, ash turns up as non-leachable slag and, thus, will be at disposal for further utilization (road construction).
The capacity of a standard module (inner diameter of 3.6 m) comes to app. 50 tons per hour.
Proceeding from this input appr. 70,000 SCM of syngas will be generated which corresponds to a possible electrical power of 140 - 150 MWel.
The first plant started its operations in the year 2000 in Eastern Germany at Schwarze Pumpe Industrial Park. A mixture of various secondary fuel materials and coal were used as feedstock.
At present, 14 BGL gasifiers have been contracted within the scope of several projects in China and India out of which three have already been put into operation. The other ones are in different stages of project implementation. As an example, a more detailed description is given for the plant situated in Hulunbeier, Inner Mongolia in the References section.
The envisaged input materials range from dried briquetted lignite to low-agglomerating hard coal. These materials are used to produce basic materials for the fertilizer industry or to produce gas as a substitute for natural gas.