Abstract: At peat mining peat is suspended in water to a slurry or suspension which is led to a dewatering plant. From the dewatering plant (13) return water is returned and used to heat the raw peat in connection with the mining area. The return water can be spread onto the moss over an area (11) at a suitable distance from the mining pit (2), thereby at least partially displacing the moss water and providing water for making a slurry, the moss water preferably being drained to the mining pit. The return water contains also a separated fine parts fraction of the peat as well as peat ash and/or other chemicals which break down the colloidal bonds of the peat and which preferably also raise the pH-value of the water which is drained into the mining pit together with said fine parts fraction.

Abstract: In a method of in situ recovering and rendering harmless material detrimental to environment, for example asbestos and the like, the material is transported together with ambient air by means of vacuum from the place in situ to a space, in which the material is separated from the air, which is led off upward, filtered and removed. The material is moved from the space and sprayed and/or injected with a substance permanently binding the material, and the material thus bound in the form of manageable units is removed intermittently or continuously from the space.

Abstract: A cake of biomass, preferably a peat cake, is dewatered by being pressed at a temperature above 90.degree. C., whereby the water in the cake is displaced by warmer water under successively increased pressure. An apparatus designed as a closed wash press is then used, in which the cake is subjected to dewatering, washing or displacement by warmer water and consequently heating as well as roller pressing.

Abstract: The invention is connected with an installation or plant for storing oil and similar petrol products in several underground storing rooms each communicating with a common oil-filled pump chamber housing submersed pumps for pumping out oil from any of the rooms. Selective pumping requires valves for selective connection of room outlet pipes with a pump inlet pipe. Submersed location of those valves in the pump chamber, according to the prior art, involves several disadvantages such as the need of draining the complete system for repair and maintenance work on the valves, and, difficulty to remote-control the valves. These advantages are, according to the invention, eliminated by the use of a dry valve chamber sealed-off from an oil-containing pump chamber housing submersed pumps.