A method of pulping wastepaper includes providing a pulping vessel with a rotor and at least one flow sensor adapted to measure slurry flow within the pulping vessel. The pulping vessel is charged with wastepaper and water to form a slurry, the amounts of wastepaper and water being present such that the slurry has consistency in the range of from 10% to 30%. The wastepaper charge in the pulping vessel is pulped at a pre-selected power level while monitoring poloidal slurry flow in the pulping vessel; and from time-to-time, water may be added to the pulping vessel when the poloidal flow falls below a predetermined lower threshold flow value in order to reduce viscosity and thereby restore poloidal flow within the pulping vessel. Doppler velocimetry is a preferred method of monitoring pulp flow. In a particularly preferred construction the rotor has a variable power drive. The inventive method is especially useful for making high quality, high brightness furnishes from wastepaper which varies from batch to batch.

A method of pulping wastepaper includes providing a pulping vessel with a rotor and at least one flow sensor adapted to measure slurry flow within the pulping vessel. The pulping vessel is charged with wastepaper and water to form a slurry, the amounts of wastepaper and water being present such that the slurry has consistency in the range of from 10% to 30%. The wastepaper charge in the pulping vessel is pulped at a pre-selected power level while monitoring poloidal slurry flow in the pulping vessel; and from time-to-time, water may be added to the pulping vessel when the poloidal flow falls below a predetermined lower threshold flow value in order to reduce viscosity and thereby restore poloidal flow within the pulping vessel. Doppler velocimetry is a preferred method of monitoring pulp flow. In a particularly preferred construction the rotor has a variable power drive. The inventive method is especially useful for making high quality, high brightness furnishes from wastepaper which varies from batch to batch.

The present invention relates to an improved method and device for treating biomass in which thermally treated biomass is discharged from a pressurized reactor and introduced into a blow tank, wherein the absolute pressure in the blow tank is maintained below atmospheric pressure. The slurry of biomass separated in the blow tank is then enzymatically treated.

The present invention relates to an improved method and device for treating biomass in which thermally treated biomass is discharged from a pressurized reactor and introduced into a blow tank, wherein the absolute pressure in the blow tank is maintained below atmospheric pressure. The slurry of biomass separated in the blow tank is then enzymatically treated.

The invention relates to a chip chute (4; 21; 31; 41) which comprises an elongated, open main body (22; 32; 42) having a rectangular transverse cross-section, and comprises further a transition portion (23; 33; 43), which connects to the elongated, open main body (22; 32; 42) and comprises a circular outlet (26; 36; 46). The invention relates further to a feeding system (1) for transporting comminuted lignocellulosic material from a vessel (2) to a pump (3) located below the vessel (2), wherein such a chip chute (4; 21; 31; 41) is arranged between the vessel (2) and the pum (3).

The invention relates to a chip chute (4; 21; 31; 41) which comprises an elongated, open main body (22; 32; 42) having a rectangular transverse cross-section, and comprises further a transition portion (23; 33; 43), which connects to the elongated, open main body (22; 32; 42) and comprises a circular outlet (26; 36; 46). The invention relates further to a feeding system (1) for transporting comminuted lignocellulosic material from a vessel (2) to a pump (3) located below the vessel (2), wherein such a chip chute (4; 21; 31; 41) is arranged between the vessel (2) and the pum (3).

A feeding arrangement for feeding lignocellulosic biomass material such as annual plant material towards a hydrolysis process includes at least one transportation device for transporting the biomass material towards the treatment process; and at least one tearing roll arranged at a predetermined distance from the at least one transportation device and being provided with tearing protrusion. The at least one tearing roll is arranged with a predetermined distance to the at least one transportation device to tear off parts of the transported material to provide a substantially continuous flow of material.

A feeding arrangement for feeding lignocellulosic biomass material such as annual plant material towards a hydrolysis process includes at least one transportation device for transporting the biomass material towards the treatment process; and at least one tearing roll arranged at a predetermined distance from the at least one transportation device and being provided with tearing protrusion. The at least one tearing roll is arranged with a predetermined distance to the at least one transportation device to tear off parts of the transported material to provide a substantially continuous flow of material.

The present invention relates to an improved method and device for treating biomass in which thermally treated biomass is discharged from a pressurized reactor and introduced into a blow tank and then a flash tank, wherein the absolute pressure in the blow tank is maintained above atmospheric pressure and the absolute pressure in the flash tank is maintained below atmospheric pressure. The slurry of biomass separated in the flash tank is then enzymatically treated. The heat from the thermally treated biomass is recovered from the latent heat of a vaporous aqueous stream withdrawn from the blow tank.

The present invention relates to an improved method and device for treating biomass in which thermally treated biomass is discharged from a pressurized reactor and introduced into a blow tank and then a flash tank, wherein the absolute pressure in the blow tank is maintained above atmospheric pressure and the absolute pressure in the flash tank is maintained below atmospheric pressure. The slurry of biomass separated in the flash tank is then enzymatically treated. The heat from the thermally treated biomass is recovered from the latent heat of a vaporous aqueous stream withdrawn from the blow tank.