Energy from Waste (EfW) in the UK has usually meant Incineration. This is an unpopular technique for 'treating' wastes prior to landfill. Incineration can vary from nearly complete destruction of hazardous wastes to 70% volume reduction in a municipal waste incinerator. This leaves 30% of concentrated, toxic ash for which a disposal route has to be found. So far, most has been land filled. .
Other satisfactory and generally acceptable alternatives for this ash have yet to be devised, and some attempts have ended in spectacular failure, such as the 2000 tonnes (Environment Agency figures) of ash containing dioxins measuring thousands of times the required safety limits. All ash deposits known to the Environment Agency in and around Newcastle have been removed by Newcastle City Council and disposed of to an appropriately licensed landfill site. This incinerator is no longer allowed to operate. .
Most incineration is either covered by European Directives (hazardous waste and municipal waste) or will be covered by a proposed Directive as and when it is passed and implemented into UK law. Most incinerators must be authorized under an Environmental Protection Act. The Directives must specify the conditions under which an incinerator must be operated, emission limits and monitoring. But Directives cannot always protect against human failure (accidental or willful). Safe emission limits have frequently been exceeded at all UK incinerators, and serious mistakes including a number of unintentional fires have occurred in recent years.
In waste incineration plants one very interesting problem arises compared to other energy producing plants. Namely, that the operators do not know the burning value and moisture content of the waste. This leads to a burning process that cannot be controlled solely by the automatic control system, but must also be based on the operator's visual inspection of the burning process and his correcting actions.