摘要:
A method for reducing the mechanical strength of solid biomass material, in particular lignocellulosic biomass, comprises mixing the solid biomass material with an inorganic material and heating the solid biomass material mixture to a toasting temperature in the range of 105° C. to 140° C. during an exposure time of from 1 minute to 12 hours. Before or after the heat treatment, which is referred to as “toasting”, the biomass material mixture is subject to flash heating. The treatment significantly reduces the mechanical energy required for reducing the particle size of the solid biomass material and is suitable as a pretreatment prior to a conversion reaction of the solid biomass material.
摘要:
Biomass (e.g., plant biomass, animal biomass, and municipal waste biomass) is processed to produce useful products, such as fuels. For example, systems can use feedstock materials, such as cellulosic and/or lignocellulosic materials and/or starchy or sugary materials, to produce ethanol and/or butanol, e.g., by fermentation.
摘要:
Methods of producing mechanical pulps from lignocellulosic material including partial defibration of lignocellulosic material in a chip press followed by liquid impregnation, preheating the lignocellulosic material for 20 seconds or less at a pressure between 7.5 and 12 bar (gauge) prior to mechanically refining the lignocellulosic material in a primary mechanical refiner at a pressure between 7.5 and 12 bar (gauge), thus obtaining a high freeness pulp.
摘要:
A system for thermomechanical refining of wood chips comprises preparing the chips for refining by exposing the chips to an environment of steam to soften the chips, compressively destructuring and dewatering the softened chips to a solids consistency above 55 percent, and diluting the destructured and dewatered chips to a consistency in the range of about 30 to 55 per cent. The destructuring partially defibrates the material. This diluted material is fed to a rotating disc primary refiner wherein each of the opposed discs has an inner ring pattern of bars and grooves and an outer ring pattern of bars and grooves. The destructured and partially defibrated chips are substantially completely defibrated in the inner ring and the resulting fibers are fibrillated in the outer ring. The compressive destructuring, dewatering, and dilution can all be implemented in one integrated piece of equipment immediately upstream of the primary refiner, and the fiberizing and fibrillating are both achieved between only one set of relatively rotating discs in the primary refiner.
摘要:
Methods of producing cellulosic or lignocellulosic materials for use in papermaking include treating a cellulosic or lignocellulosic dry feedstock having a first average molecular weight with ionizing radiation, and controlling the dose of ionizing radiation such that the average molecular weight of the feedstock is reduced to a predetermined level. A method of producing an irradiated paper product includes treating a paper product including a first carbohydrate-containing material having a first molecular weight with ionizing radiation, and controlling the dose of ionizing radiation so as to provide an irradiated paper product with a second carbohydrate-containing material having a second molecular weight higher than the first molecular weight. Pulp and paper products are produced.
摘要:
A chip pretreatment process which comprises conveying the feed material through a compression screw device having an atmosphere of saturated steam at a pressure above about 5 psig, decompressing and discharging the compressed material from the screw device into a decompression region, feeding the decompressed material from the decompression region into a fiberizing device, such as a low intensity disc refiner, where at least about 30 percent of the fiber bundles and fibers are axially separated, without substantial fibrillation of the fibers. In a more specific form the invention is directed to a process for producing mechanical pulp, including the steps of fiberizing wood chip feed material in a low intensity disc refiner until at least about 30 percent of the fibers are axially separated with less than about 5 percent fibrillation, and subsequently refining the fiberized material in a high intensity disc refiner until at least about 90 percent of the fibers are fibrillated. In another form the invention combines chip fiberizing with chemical treatments, for improving the pulp property versus energy relationships.
摘要:
A manufacturing process of a paper substrate intended to be vulcanised or parchmentised, consisting in: subjecting, in a dry state, the cellulose fibres to energy radiation; defiberizing and refining in an aqueous environment the irradiated fibres until a homogenous fibre solution is obtained; forming a web from the obtained fibre suspension, which is then drained and dried to obtain the actual paper substrate.
摘要:
A method and apparatus for pretreating or conditioning lignocellulose fiber containing feed material in preparation for conversion to pulp. Wood chips are pretreated under conditions of elevated temperature, pressure and humidity and subsequently compressed to cause destructuring of the fibers of the feed material. The pretreated wood chips are then converted to pulp using such methods as the ground wood pulping process or chemical digestion process.
摘要:
A method for refining lignocellulose-containing material into pulp in a disc refiner comprises preheating the material to a temperature greater than the glass transition temperature of lignin in the material, and holding this temperature for under one minute. The heated material is then subject to high speed refining in a disc refiner to produce pulp. The resulting pulp may then be subject to secondary refining steps to produce paper quality pulp. The preheat retention time is preferably in the range of 5-30 seconds, and can be controlled as a process variable to optimize energy savings, pulp strength, and optical qualities. High quality pulp can be obtained with preheat at high temperature and low retention time, followed by primary refining at disc speed of at least 2300 rpm.
摘要:
A single drive motor is connected by a speed reducer directly to the shaft of one roll of the two aggressive surfaced rolls which form a chip destructuring nip. One roll is dynamically positionable perpendicular to its axis of rotation to open and close the nip. Each roll turns on a shaft positioned along the axis of the roll which is mounted to a frame by bearings. Only the non-positionable roll is driven directly by the drive motor. The roll which is dynamically positionable is driven by a tire arrangement mounted about the axes of the rolls. Opposed tires mounted on the spaced apart parallel shafts form a clutch-like means for driving the dynamically positionable roll.