Patent ID: 8088249

Claim:
A method for a continuous steam pre-treatment of chips during a production of cellulose pulp, comprising: feeding untreated chips, that are at a temperature that corresponds to an ambient temperature, to a steam pre-treatment vessel, pre-treating the untreated chips with steam to pre-heat the chips and expel air that is contained in the chips, where the steam pre-treatment vessel has a chips inlet defined therein at a top and an outlet defined therein at a bottom, adding steam (ST) to a bed of chips that has been established in the steam pre-treatment vessel through a steam generation device, establishing a temperature gradient in the bed of chips, establishing a high temperature low down in the bed of chips, establishing a low temperature at an upper surface of the bed of chips, the low temperature being a temperature lower than the high temperature, detecting an operational parameter that exceeds a threshold value indicating a blow-through of steam up through the bed of chips, arranging a regulator valve in a connecting line between the source (CS) of cooling liquid and the pre-treatment vessel, and the operational parameter exceeding the threshold value triggering an opening of the regulator valve through an activation device to permit a cooling liquid from a source (CS) to flow therethrough, and injecting the cooling liquid into the top of the pre-treatment vessel.