Technology Design Of 20,000T/a Fine Aluminum Hydroxide Line

Aluminum hydroxide, aluminum hydroxide powder, this product has alreadybecome one of the main choice of materials to a prescription, which is used tosynthesize materials without halogen-fire retardant. Because this kind of product hasthese advantages as the following: the grain of this product is fine, the surface area of itis large, and it has well dispersibility and three functions of filing, flame retardant andsmoke abatement. Meanwhile, this product is non-toxic and odorless and it does notproduce the second pollution. Recent years, there is a increasingly need for thealuminum hydroxide powder both home and abroad.This paper put forward an advice that adding another new production line foraluminum hydroxide powder at 20 thousand ton every year, according to the situation ofaluminum hydroxide powder market supply and demand home and abroad at presentand competitive analysis on aluminum hydroxide powder from branch company inShandong. On the base of keeping the advantages of the existed powder productiontechnology process, this technology modified the original technology and equipmentplan at these six crucial working procedures like liquid-solid separation, washing,dryness, depolymerization, heat addition, heat exchange and so on. Being applied thistechnology, the degree of automation and work productivity of each working procedureon the new production line are enhanced greatly, and each target got optimized and thecost of unit manufacture became lower to a great extend.Due to the base of process selection demonstration, material balance and energybalance, this paper took fully consideration of the property of technology and properutilization of energy, it made selective calculations of process technology parametersand key equipments and then finished configuration of technology and arrangement of a flat surface. Furthermore, this paper did technical and economic anlysis of this project’sprofitable ability.This paper did research mainly on these contents:(1) Using vertical filter press with relativly high level of automation on theliquid-solid separation process, it could lower the amount of liquid attached to the mostdegree, save washing water and energy cost of flash distilled water;(2) In the washing process, it chose vacuum filter with mobile disk belt style sothat this could raise washing efficiency and reduce the amount of washing water to themaximium and cost of steam;(3) In the dryness process, rotation flash vaporization dryer was selected. Thisdevice is of high heat efficiency and low energy cost, so that it could improve thecapacity of equipments and reduce the cost of product.(4) Using combination style of mechanical scatter machine and multiple classifer,it could not only save energy cost, but also fully make sure the safety of the grain of thisproduct.(5) Made plat type heat exchanger cooled for two stages by using slurry andrecycling water after decomposition and this method properly utilized heat resource andreduced the total energy cost of product in order to optimize the technologyconfiguration;(6) The flash vaporization dryer was heated directly by natural gas, this couldreduce the cost for the dryness of product to the most degree.The technical and economic target of this technology has already reachednationally advanced level and rewarded as the "National high quality project prize in2009".