METHOD TO REDUCE POWER CONSUMPTION IN PRODUCTION OF THERMOMECHANICAL WOOD PULP BY MEANS OF LOW-TEMPERATURE GRINDING OF WOOD PULP OF LOW AND MEDIUM CONCENTRATION Russian patent published in 2010 - IPC C09K5/00 D21B1/00 D21D1/00 D21D1/40 

FIELD: wood working industry.

SUBSTANCE: method for heat recuperation in grinding of wood pulp includes ejection of pressurised wood pulp from high-pressure refining machine; introduction of at least filtrate from pressurised wood pulp into pressurised expansion cyclone; transfer of heat from expansion cyclone to water for its heating, and usage of heated water in process of wood pulp grinding. Meanwhile wood pulp is a pressurised suspension of fibres in liquid, besides, wood pulp suspension is pressurised with 3 to 6 bar. Pressurised wood pulp is a suspension of low or medium concentration and has the temperature of not lower than 140°C in the refining machine. Expansion cyclone maintains pressure in wood pulp at the level of 3-6 bar. Heat exchanger is additionally used for heat transfer. Wood pulp is ground in pulp mill, and a separate flow from pressurised expansion cyclone is used in a separate process at pulp mill.

EFFECT: increased power consumption in process of production of mechanical wood pulp.

12 cl, 3 dwg