Communal biomass conversion plants. From idea to reality

The first Danish biomass conversion plant for the production of methane was built in the nineteen seventies. It was just a little plant based on manure slurries from a local herd of farm animals. It was not until the nineteen eighties that larger plants were established so that enough methane could be produced as part fuels for decentral district heating and/or cogeneration plants. By November 1995 there were 15 communal biomass conversion plants producing methane in Denmark, three more plants were in the course of establishment and a number of similar projects were on the drawing board. The history of this development is narrated and plans for the future are indicated. The document also deals with the technological aspects, operational economics, environmental impacts, resources and re-use, wastes used as fertilizers, household organic wastes and sewage slam, standards of hygiene and reduction of infection risks, exports and commercial development and socio-economic evaluations in addition to areas within this field which need special attention in the very near future. It is concluded that the economics of Danish biomass conversion plants have improved significantly since 1987, and many older plants have been brought right up to date. Improvements in technology and an increase in the supply of industrial wastes have increased production. Details of the basis of many other betterments that have taken place in recent years are also given. (AB) 27 refs