Applications of Self-Cleaning Heat Transfer Technology with Liquid-Solid Fluidized Bed to Preheat Exchangers for Well and Rock Salt Bittern

摘要

Calcium, magnesium and sulfate ions in the well and rock salt bittern can form hard scale on heat transfer surface in preheat exchanger during bittern preheating; this will result in some disadvantages for the production of the refined salt from well and rock bittern. In the present study, the liquid-solid fluidized bed heat transfer technology has been applied to the bittern preheat exchangers, and the scaling prevention effect of the inert solid particles has been investigated. The results indicated that the liquid-solid fluidized bed can inhibit gypsum scale depositing on the heat transfer surface under a certain inert solid particles concentration and fluid rate. After the preheat exchangers with liquid-solid fluidized bed having been operated for 150 days, the heat transfer surface can be preserved clean, and the temperature of the outlet bittern can remain constant. The capacity of the refined salt production has been obviously promoted, and the great economic benefit has been produced due to application of the liquid-solid fluidized bed heat transfer technology.