Abstract: Method and apparatus for producing fibre pulp and fuel out of municipal waste or for producing fibre pulp out of waste paper. To control the microbe content, the retention time of the process is kept shorter than 12 hours, advantageously shorter than 6 hours. This is achieved by minimizing the total liquid volume of the process and by increasing the amount of water being passed to water treatment from the process, which water, having been purified, is possibly returned to the process. The method may also include a phase in which the pulp is treated thermally in order to destroy the microbes present in it.

Abstract: Water is recovered from sludge, such as from sewage treatment plants, or wood processing or food processing industries, by either electrically ionizing the sludge or treating the sludge with ultrasound, and then adding coagulant to the sludge to effect coagulation. Prior to or substantially simultaneously with coagulation, the sludge is vigorously mixed, and then the sludge is flocculated and water is mechanically removed from the flocculated sludge. Water removal can be optimized by adding news print pulp, or a tenside, to the sludge just prior to mechanical removal. Free water may also be removed by filtering just prior to mechanical removal, and mechanical removal can take place in two consecutive stages, first a low pressure (1-5 bar) stage to produce a cake, and then the cake is broken up and subjected to a high pressure (5-60 bar) stage.