Cogeneration plant for the continuous production of electrical and thermal energy from solid woody biomass, the latter being selected from among wood in the form of woodchips, vine branches, shrubs and underbrush, grain, hay, animal litter, suitably-treated muds, shells and kernels, suitably-treated husks, fibrous cultures and compositions thereof, the plant including at least one first container and at least one second container connected by at least one interconnection duct, the first container including the components suitable for inducing the transformation of the biomass into syngas including H.sub.2 and CO; the plant providing for a particular step of screening, drying and briquette-making on board the machine of the solid woody starting biomass.

An apparatus for thermal processing of waste having organic and inorganic components comprises at least a treatment station, a cooling station and a treated material-removal station, and at least three crucibles. The treatment station is adapted to thermally treat the organic components and/or inorganic components located in a given one of the crucibles located at the treatment station. The so-treated components in this given crucible are adapted to then be cooled at the cooling station, before the treated components located in the given crucible are removed therefrom at the treated material-removal station. The three crucibles are mounted on a turntable so that the three crucibles are each at one of the stations, before synchronously all moving to each crucible's next station.

In apparatus and method for waste treatment by pyrolysis, treated waste is flushed through a grid (18) to trap recyclable material in the pyrolysis chamber (24). Pyrolysis is carried out at a temperature of from 400-700 C. and off gases are dissolved in a solution in scrubber (13) for disposal in a water course. Water is introduced into the chamber as superheated steam via pipes (5) so as both to flush away treated material and clean the chamber. Recyclable waste is separated from non-recyclable by treating non-recyclable waste by pyrolysis, and flushing treated non-recyclable waste away through liquid exhaust (8). Apparatus is made as a modular, free-standing unit and comprises plugs for connection to an electricity supply, to a water supply, and to a sewage system (16) and has a chamber with a volume in the range 0.01-0.5 m.sup.3.

In a boiler, a space is reserved to expand the boiler by increasing the front and rear walls. To expand the boiler, wall additions are added to increase the width of the front and rear walls. After the expansion, the distance between the front and rear walls is substantially the same distance between the front and rear walls before the expansion.