| 摘要 |
A process for disposing of sanitary sewage sludge by producing a pumpable slurry of sewage sludge and low grade solid carbonaceous fuel and burning said slurry as fuel in a partial oxidation gas generator, furnace, or boiler. The aqueous slurry of sewage sludge is concentrated by removing water by means of a conventional belt filter press or presses. Prior to and/or immediately after said concentrating step particles of low grade solid carbonaceous fuel e.g. lignitic coal, peat, wood and cellulose-containing materials are mixed with the slurry of sewage sludge. The dewatered slurry of sewage sludge and low grade solid carbonaceous fuel is hydrothermally treated in three stages and excess water is separated by flash evaporization and/or centrifuging. The viscosity of the slurry of sewage sludge and low grade solid carbonaceous fuel is reduced to less than about 2000 centipoise by shearing to produce a pumpable slurry which is burned with a free-oxygen containing gas in a partial oxidation gasifier, furnace, boiler, or incinerator to produce a hot raw effluent gas stream. In a preferred embodiment, the effluent gas stream is cleaned and purified and non-contaminating ash and slag are separated. By this process, noxious sewage sludge may be disposed of without contaminating the environment. By-product synthesis gas, reducing gas, or fuel gas may be produced.
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