TECHNOLOGY FOCUS - ENVIRONMENT - Preferred Method: In processing manure and/or biomass, n the manure is from farm animals, in particular pigs or cows. The manure is pig manure. The acidified manure obtained by step (a) is separated in step (b) without an intermediate processing step. Liquid fraction obtained by step (b) is filtered prior to addition to the second reactor used in step (c), which filtering preferably comprises microfiltration. Liquid fraction obtained by step (b) or the filtered liquid fraction is fed into the second reactor of step (c) so that the pH of the contents of the second reactor does not become less than pH 6.5, preferably not less than pH 7. The second reactor comprises a fluidized bed reactor or a continuous-stirred tank reactor including a settler. Liquid fraction obtained by step (c) is added to a third reactor, which preferably comprises a fluidized bed reactor, which third reactor comprises liquid fraction having a pH of more than pH 8.5, preferably more than pH 9, to allow dissolved phosphates to precipitate. Formation of phosphate-comprising crystals, preferably struvite crystals, in the second and/or third reactor is facilitated by addition thereto of seed crystals and/or a solution comprising a magnesium salt and/or a solution comprising a calcium salt. Solid fraction obtained by step (b) is washed with water and separated again in a solid and liquid fraction. The first reactor used in step (a) is added material obtained from a premixing container, which premixing container comprises a solid fraction of separated manure and/or biomass in combination with: the liquid fraction obtained by step (b) and/or the liquid fraction obtained from the washing/separating step, and/or the liquid fraction from the second reactor and/or the liquid fraction from the third reactor. The material obtained from the premixing container comprises a dry matter content of 15 to 20 percentage by weight. Liquid fraction obtained by step (b) and/or the liquid fraction obtained from the washing/separating step and/or the liquid fraction from the second reactor, and/or the liquid fraction from the third reactor, is added to the premixing container in dependency of the pH of the contents of the premixing container. Preferred Installation: In the installation, one outlet of the first reactor is directly connected to an inlet of the separator via a suitable conduit. Installation further comprises a third reactor, preferably a fluidized bed reactor, having at least one inlet and at least two outlets, which inlet is connected to an outlet of the second reactor via a suitable conduit. Installation also comprises a premixing container for premixing unfermented manure, preferably the solid fraction, which premixing container comprises at least one outlet which is connected via a suitable conduit to an inlet of the first reactor, which premixing container comprises a first inlet connected via a suitable conduit with an outlet of the separator for receiving liquid fraction from the separator, which premixing container preferably comprises a second inlet connected via a suitable conduit with an outlet of a washer/separator to receive liquid fraction from the washer/separator, which washer/separator is intended to wash and again separate the solid fraction obtained from the separator, and/or which premixing container preferably comprises a third inlet connected via a suitable conduit with an outlet of the second reactor and/or third reactor, where preferably the rate of inflow through the first inlet of the premixing container can be regulated by the pH of the contents of the premixing container. An inlet of the first reactor is equipped with a level-indicator controller (LIC), where this inlet is preferably connected to an outlet of the premixing container to allow controlled inflow in the first reactor of material from the premixing container. The first and/or second and/or third reactor and/or premixing container comprise means for mixing the contents and/or a heat exchanger to allow the contents to be kept at a desired temperature. Separator for separating fermented manure and/or biomass into a liquid and a solid fraction comprises a filtration or centrifugation means, preferably selected from a particle filter, a vibrating sieve, a curved screen, a screw press, a press auger, and a belt filter. A filtrating device, preferably a microfiltrating device, is connected to an outlet of the separator for receiving liquid fraction and to an inlet of the second reactor, preferably a pH-regulable inlet. Installation further comprises a washer/separator intended to wash and again separate the solid fraction obtained from the separator, where one inlet of the washer/separator is connected via a suitable conduit to an outlet of the separator for receiving solid fraction from the separator, and where one inlet of the washer/separator is connected via a suitable conduit to a water-source for receiving water and/or connected via a suitable conduit to the outlet of the second and/or third reactor to receive liquid fraction, where one outlet of the washer/separator is connected via a suitable conduit to a premixing container, preferably the premixing container, and where the washer/separator comprises an outlet for transport of solid fraction out of the installation. Installation also comprises at least one buffering container comprising at least one inlet and at least one outlet, where one inlet is connected to one outlet of the filtrating device and one outlet which is connected to one inlet of the second reactor, and/or one buffering container of which one inlet is connected to one outlet of the separator for receiving liquid fraction and one outlet which is connected to one inlet of the second reactor, and/or one buffering container of which one inlet is connected to one outlet of the second and/or third reactor for receiving liquid fraction and one outlet which is connected to one inlet of the premixing container, and/or one buffering container of which one inlet is connected to one outlet of the washer/separator and one outlet which is connected to one inlet of the premixing container, and/or a buffering container of which an inlet is connected to an outlet of the first reactor for receiving acidified manure and/or biomass and an outlet which is connected to an inlet of the separator. It further comprises a flow-indicator controller (FIC) for measuring the outflow of liquid out of the installation. The installation is equipped with a master/slave to allow the outflow of liquid out of the installation to be compensated by the inflow of water. EXAMPLE - No suitable example given.