A system for silica removal in a process for prehydrolysis kraft pulp production, the system comprising at least: a vessel having a top section and a bottom section; a chip inlet arranged in the top section for introduction of wood chips into the vessel; a steam inlet arranged in the top section for introduction of steam into the vessel; a first fluid inlet arranged in the vessel for introduction of fluid into the vessel, to provide a chip slurry having a chip slurry temperature in a soaking zone disposed below the top section, the chip soaking zone being a zone in which wood chips are submerged in fluid for a specified soaking time; a chip slurry outlet arranged in the bottom section and connected to a chip slurry transportation pipe for transport of the chip slurry; a second fluid inlet arranged in the bottom section and/or in the chip slurry transportation pipe for dilution of the chip slurry in the chip slurry transportation pipe to a liquid-to-wood ratio of at least 10:1 with a dilution fluid having a temperature higher than the chip slurry temperature; a dewatering device connected to the chip slurry transportation pipe for dewatering the chip slurry and creating a first flow of chip slurry having a liquid-to-wood ratio of less than 3:1 and a second flow of silica-containing fluid; and a return pipe connected to the dewatering device for transport of the second flow of silica-containing fluid and connected to the first fluid inlet and/or to the second fluid inlet, wherein at least one silica separator is arranged in the return pipe, and that the soaking time is between 30 minutes to 120 minutes, that the chip slurry temperature is 95-105 °C, and that the dilution fluid temperature is 110-130 °C. a vessel having a top section and a bottom section; a chip inlet arranged in the top section for introduction of wood chips into the vessel; a steam inlet arranged in the top section for introduction of steam into the vessel; a first fluid inlet arranged in the vessel for introduction of fluid into the vessel, to provide a chip slurry having a chip slurry temperature in a soaking zone disposed below the top section, the chip soaking zone being a zone in which wood chips are submerged in fluid for a specified soaking time; a chip slurry outlet arranged in the bottom section and connected to a chip slurry transportation pipe for transport of the chip slurry; a second fluid inlet arranged in the bottom section and/or in the chip slurry transportation pipe for dilution of the chip slurry in the chip slurry transportation pipe to a liquid-to-wood ratio of at least 10:1 with a dilution fluid having a temperature higher than the chip slurry temperature; a dewatering device connected to the chip slurry transportation pipe for dewatering the chip slurry and creating a first flow of chip slurry having a liquid-to-wood ratio of less than 3:1 and a second flow of silica-containing fluid; and a return pipe connected to the dewatering device for transport of the second flow of silica-containing fluid and connected to the first fluid inlet and/or to the second fluid inlet, wherein at least one silica separator is arranged in the return pipe, and that the soaking time is between 30 minutes to 120 minutes, that the chip slurry temperature is 95-105 °C, and that the dilution fluid temperature is 110-130 °C.