Abstract: The present invention relates to regulation of the p H of a liquefaction process. Presented is a method for treatment of a biomass feedstock wherein the biomass feedstock is subjected to liquefaction, at a p H of at most 4, by treatment with hot compressed liquid water (HCW) at subcritical and/or supercritical conditions to improve the conversion efficiency. The present invention is also directed to quenching of a liquefaction process according to above, preventing, minimizing or eliminating clogging and/or fouling of sticky biomass components in process equipment during processing as according to above, and to the use of additives in a biomass liquefaction process.

Abstract: The present invention describes a process for quenching a hydrothermal, dilute acid hydrolysis reaction of a biomass feedstock, wherein degradation of an aqueous monomer and/or oligomer sugar mixture is slowed down or stopped by flash cooling of the aqueous monomer and/or oligomer sugar mixture, and wherein the flash cooling ensures that a fraction of dissolved and volatile degradation byproducts are removed by a forming vapor stream, and wherein a lignin component, if present, is solidified into a structure with good de-watering characteristics, allowing for subsequent removal of the lignin component by separation, said process resulting in a hydrolyzed solution of sugar monomers and/or oligomers.

Abstract: The present invention describes a process involving liquefaction of a biomass slurry by treatment in hot compressed water (HCW), said process comprising: —a first decomposition step being performed at an average pH level of at most 4.5, wherein a hemicellulose fraction in the biomass slurry is decomposed to water soluble mono- and/or oligomers, and wherein a cellulose fraction undergoes a pre-treatment for decrystallization of the cellulose polymer; —a separation step; and —a second decomposition step, wherein the cellulose fraction in the biomass slurry is decomposed to water soluble mono- and/or oligomers; wherein both of the first and second decomposition steps are performed at sub-critical temperatures implying relatively moderate conditions.

Abstract: The present invention relates to regulation of the p H of a liquefaction process. Presented is a method for treatment of a biomass feedstock wherein the biomass feedstock is subjected to liquefaction, at a p H of at most 4, by treatment with hot compressed liquid water (HCW) at subcritical and/or supercritical conditions to improve the conversion efficiency. The present invention is also directed to quenching of a liquefaction process according to above, preventing, minimizing or eliminating clogging and/or fouling of sticky biomass components in process equipment during processing as according to above, and to the use of additives in a biomass liquefaction process.

Abstract: The present invention relates to a method of treating organic materials to produce methane gas, comprising the steps of: a) subjecting an organic feedstock comprising organic materials to a liquefaction process at subcritical conditions in at least one reaction stage, to obtain a mixture containing low molecular weight materials and optionally lignins; b) subjecting the obtained mixture containing low molecular weight materials and optionally lignins, to a methane fermentation process; wherein said organic feedstock comprises liquid water and/or is combined with liquid water before and/or during said liquefaction, and the subcritical conditions for said at least one or more reaction stage(s) in a) is a temperature of 280-374° C.