Abstract: A method for separating and recovering compounds from biomass is provided. In the method, an aqueous extraction fluid in essentially gaseous phase, such as steam, is propagated through a reaction area containing biomass feedstock. When extraction fluid advances through the biomass feedstock, in predetermined reaction conditions, a target compound separates from the essentially solid feedstock matter and travels, with the extraction fluid, towards the end of the reaction area, in where the target compound is recovered in the form of an essentially liquid medium. The method is beneficial for extracting long-chain hemicelluloses from cellulose-containing feedstocks.

Abstract: A method and a system for continuous purification of wastewater and/or utility water, wherein peracetic acid is metered into the wastewater, the flow of the wastewater, redox potential and the concentration of peracetic acid are measured, and the metering of peracetic acid is adjusted relative to the variation in the flow and on the basis of the concentration of peracetic acid and redox potential.

Abstract: Waste water in an activated sludge waste treatment plant is treated with a quantity of peracetic acid which destroys harmful filamentous microorganisms while preserving the beneficial microorganisms used in the purification procedure.