Provided are compositions and processes concerning efficient downstream processing of products derived from organic acids pretreatment of plant materials.

A method for transforming a black liquor, comprising the following steps: a) supplying a black liquor, b) gasifying the black liquor by means of supercritical water gasification in the presence of a hydrogenated carbon-free fuel, by means of which reaction products are formed, c) cooling the reaction products, by means of which a gaseous mixture is obtained which comprises at least methane and a green liquor comprising at least sulphur in the form of NaHS, Na.sub.2S and H.sub.2S.

The invention is directed to compositions and processes concerning efficient downstream processing of products derived from organic acids pretreatment of plant materials.

The invention relates to a process for isolation of hemicelluloses from biomass pulping process waters or spent liquors with removal of suspended solids, concentration of the product and purification of the product by removal of inorganic salts and low molecular weight substances. It is characterized in that the hemicellulose isolation process conditions at several separation/purification stages are adjusted separately by e.g. pH adjustment. The invention further relates to a plant for carrying out the process. With such process and plant it is possible to recover most of the suspended solids, especially xylan and other hemicelluloses.

The disclosed technology includes a membrane-based device configured to concentrate black liquor, which results from papermaking. Certain embodiments may comprise a nanofiltration membrane configured to remove lignin from black liquor, and the nanofiltration membrane may include a first macroporous polymer substrate and a first graphene oxide membrane covering the first macroporous polymer substrate. Some embodiments may comprise a reverse osmosis membrane, which may include a second macroporous polymer substrate and a second graphene oxide membrane covering the second macroporous polymer substrate.

A deicer composition is disclosed. The deicer composition may comprise water, a metal chloride salt, and a biopolymer composition derived from wheat straw, alfalfa, or other cereal grain straws. The biopolymer composition may include inorganic material and a copolymer comprised of lignin and polysaccharides. The biopolymer composition may have an average molecular weight of between 3500 and 5500 Daltons. The metal chloride salt may be selected from magnesium chloride, calcium chloride, and sodium chloride.

The invention concerns an apparatus (10) for separation of components with different volatility in a mixed fluid, said apparatus (10) comprising: a first heat exchanging unit (100) provided with first and second flow path structures (131, 132) forming separate flow paths for a first and a second fluid flow through the first heat-exchanging unit (100); an inlet (118) for feeding the mixed fluid to the apparatus (10); an inlet (119) for feeding steam to the apparatus (10); an arrangement for feeding a cooling medium through the apparatus (10), wherein said arrangement comprises at least one cooling medium inlet (105, 106, 107, 108). The invention is characterized in that the apparatus (10) comprises a second heat-exchanging unit (200) provided with third and fourth flow path structures (233, 234) forming separate flow paths for a first and a second fluid flow through the second heat-exchanging unit (200), wherein the cooling medium arrangement comprises at least one cooling medium inlet (205, 206, 207, 208) arranged in fluid communication with the fourth flow path structure (234) and wherein the first and third flow path structures (131, 233) are arranged in fluid communication with each other.

A process for depolymerization of lignin, the process including using at least one catalyst internal to a pulp mill for performing catalytic treatment and separation of biomass components into cellulose and lignin rich material is provided.

A process for the isolation of lignin from black liquor and modification of lignin for use in many plastic applications is disclosed. The isolation of lignin consists of removing all of the non-lignin components from black liquor solution. The non-lignin components including but not limited to organic acids, sugars, and inorganic materials can be removed using either solvent extraction or ion-exchange resin or a combination of both methods. The isolated lignin is water soluble. The non-lignin components can be further isolated and sold or reused in the pulping or lignin isolation processes. The isolated lignin can be further modified in order to meet the needs of the desired plastic application.

The invention is characterised in the steps of a) performing a first separation of the mixture in a first centrifugal separator, resulting in a first heavy fraction comprised of the heavy phase with only small amounts of impurities in the form of the light phase and a first light fraction comprising of the light phase with impurities in form of the heavy phase; and b) performing a second separation of the first light fraction in a second hermetic centrifugal separator of purificator type, resulting in a second heavy fraction comprised of the heavy phase with impurities in the form of the light phase and a second light fraction comprised of the light phase with only small amounts of impurities in the form of the heavy phase. The invention also relates to a device.