HEAT EXCHANGER Russian patent published in 1999 - IPC

FIELD: regenerative heating of unboiled steam-and-pressure cured pulp by heat of boiled pulp; alumina production. SUBSTANCE: heat exchanger has cylindrical shell with heat-exchange tubes mounted inside it; heat-exchange tubes are secured in tube sheets coupled with solution chambers for medium being heated. Cylindrical shell consists of three parts: central part, lower widening part and extension of central part received by its lower widening part forming clearance between last and lower tube sheets. Heat exchanger is provided with branch pipes for delivery and discharge of medium being heated and heat-transfer agent; heat-transfer agent supply branch pipe is located opposite central part extension above clearance. Such construction excludes direct action of heat-transfer agent (boiler pulp) possessing high temperature and abrasivity on heat-exchange tubes, thus protecting them against wear. EFFECT: enhanced efficiency and reliability. 1 dwg