Mixed solid wastes, gasification

Prior to the erection of the pilot plant at Velsen, a small test reactor consuming up to 60 kg/h of solid waste was installed at Neunkirchen next to an incinerator, which was to prove feasibility of solid waste gasification. During 2 1/2 years of test runs amounting to about 10 000 hours, all kinds of materials were charged to this reactor. For instance rubber, plastics, wood, used lubricating oil mixed with household waste. A reasonable gas composition could be maintained for any length of time ... 

One of the major advantages of gasification for the conversion of wastes is that it requires little pretreatment or sorting of the starting materials. Consequently, in many gasification processes plastic and rubber wastes are converted simultaneously with other solid wastes. This section describes some of the processes currently used for the gasification of mixed solid wastes. 

Arcus gasification combuster is described and the principles upon which it works are explained. This combuster combines solid fuel gasification with the burning of the lean gases produced on a small capacity scale. The types of solid fuels which can be used are listed and these include segregated municipal waste and industrial waste such as rigid PU foam and plastics mixed with other materials. Uses of the gas produced are included. 

The ChemChar process is a patented, ex situ method for the treatment of hazardous and mixed wastes using reverse-burn gasification. Organic components of the treated waste are converted to a combustible gas and a dry, inert solid. The solid can be mixed with cement to prevent leaching of radioactive or heavy-metal constituents retained in the char residue after gasification, or the solid can be further reduced by forward-bum gasification. 

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