Abstract: The invention relates to a process for treating wastewater or sludge, in which a wastewater or sludge stream (2) is conveyed through a first mixing unit (15), wherein a base/alkaline solution (17) or a phosphate-fixing compound/liquid containing a phosphate-fixing compound (17) is metered or mixed into the first mixing unit (15). The invention further relates to a device (100) for treating a wastewater or sludge stream (2), especially for carrying out the aforementioned process.

Abstract: In a method for disintegrating organic substrates, an alkaline solution is added as pH-altering solution to the substrate and said substrate is then treated with steam, or steam is added, for heating to a temperature below 100° C. Under pressureless conditions, the heated substrate admixed with alkaline solution is subjected to a residence time. Preferably, the organic substrates are sludges from wastewater treatment plants.

Abstract: The invention relates to a process for separating off and/or recovering nitrogen compounds, in particular for separating off ammonia and/or recovering or producing nitrogen fertilizer, from a liquid or sludge substrate, in which a liquid or sludge substrate is introduced into a degassing vessel to which subatmospheric pressure is applied and ammonia gas formed is introduced by means of a vacuum pump into at least one scrubber which is located downstream of the degassing vessel and to which subatmospheric pressure is applied and into which acid is introduced, wherein the acid or an ammonium salt-containing liquid obtained in the at least one scrubber is taken off from the at least one scrubber, cooled and subsequently sprayed back into the at least one scrubber. The invention further relates to a plant for carrying out such a process.

Abstract: In a method for the hydrolysis of liquid, organic substrates (1), the substrate to be hydrolysed is introduced into a circulation loop for heating, where an equal amount of hydrolysed substrate (1) is displaced from the circulation loop (6, 7, 8, 9). An appropriate system can have a circulation loop, a feed device, a circulation pump for generating a circulation flow in the circulation loop, and a heater for heating and reheating the circulation flow.

Abstract: The invention relates to a process for separating off and/or recovering nitrogen compounds, in particular for separating off ammonia and/or recovering or producing nitrogen fertilizer, from a liquid or sludge substrate, in which a liquid or sludge substrate is introduced into a degassing vessel to which subatmospheric pressure is applied and ammonia gas formed is introduced by means of a vacuum pump into at least one scrubber which is located downstream of the degassing vessel and to which subatmospheric pressure is applied and into which acid is introduced, wherein the acid or an ammonium salt-containing liquid obtained in the at least one scrubber is taken off from the at least one scrubber, cooled and subsequently sprayed back into the at least one scrubber. The invention further relates to a plant for carrying out such a process.