Combustion of low-calorie fuelled boiler by sprayed addition of sewage and chalk

摘要

In a process to heat a water boiler or fluidised bed boiler, the boiler is fired with fuel consisting of coal dust, municipal refuse or other low-calorie fuel such as wet sewage sludge. The novelty is that: (a) a mixture is prepared containing a suspension of sewage sludge and lime; (b) the suspension (a) is discharged by jets onto the low-calorie e.g. coal dust fuels, or into effluent smoke recovered through an exhaustion system, or into the flow of effluent smoke prior to discharge; (c) the suspension (a) is in a fluid state in which it may be conveyed by hydraulic or pneumatic means, and consists of sludge and milk of lime, and is prepared in a buffer tank by the addition of chalk into the sludge.