The invention discloses a
gibbsite flash evaporation-free dissolving-out method which comprises the following steps: pre-desiliconized ore pulp at 92-95 DEG C enters a
heat exchanger A, in the
heat exchanger A, high-temperature dissolved-out
slurry and the pre-desiliconized ore pulp are subjected to heat exchange, so that the temperature of the pre-desiliconized ore pulp is gradually increased to 110-115 DEG C, then the pre-desiliconized ore pulp enters a
heat exchanger B, in the heat exchanger B, through new steam condensate water, the temperature of the pre-desiliconized ore pulp is increased to 110-115 DEG C; the pre-desiliconized ore pulp is continuously heated, the temperature of the pre-desiliconized ore pulp is increased to about 120 DEG C, then the pre-desiliconized ore pulp enters a heat exchanger C, in the heat exchanger C, the pre-desiliconized ore pulp is further heated through new steam till the temperature of the pre-desiliconized ore pulp reaches the
dissolution temperature of 155-160 DEG C, then the pre-desiliconized ore pulp enters a heat preservation staying
system to stay for 30-60 min, and a
dissolution reaction is conducted; the
slurry subjected to heat preservation
dissolution enters a heat exchanger A to be subjected to liquid-
liquid phase-free heat exchange, and the temperature of the
slurry subjected to heat exchange is reduced to 109 DEG C or below. The method simplifies the process flow, saves the investment and
land occupation, and improves the economic benefit of
alumina production.