摘要:通过对国内外各种氧化铝生产工艺进行了广泛深入的分析和对比,并根据本设计的具体条件,确立了本设计的工艺流程。经过论证,确定了生产的工艺参数:分解溶液的苛性比αk为1.50,精液碱浓度为155g/l;母液αk为3.0,溶出碱浓度为210g/l;溶出温度265℃,溶出赤泥A/S=0.88,N/S=0.5,赤泥分离底流L/S=3.0,赤泥洗涤底流L/S=2.5。其中,本次设计的重点是赤泥洗涤车间。通过计算分析,设计了五次反向洗涤的工艺流程,并对热损失进行了验算。同时,还对全厂生产成本进行了计算,对种分车间的工作人员进行分配。最终确定主体设备的选型和车间平面布置,该车间配置有两台直径为30m高15m的分离沉降槽,5台直径为26m高15m的洗涤沉降槽,10台直径为3m高6m的水力混合槽,5台离心泵,加上沉降槽基础,整个设备安置高度约为30m。该生产区域长约为312m,宽约为108m,各区域有宽阔的路段,方便赤泥的运输及交通往来。
关键字:氧化铝生产;拜耳法;三水铝石;溶出
ABSTRACT:Based on extensive analysis of the international and domestic alumina production technology,and the specific requirements of the design, the production process is established. With demonstrating, the parameters of production process are obtained: the αk, Nk of pregnant liquor is 1.50 and 155g/l, respectively; the αk, Nk of spent liquor is 3.0 and 210g/l, respectively; the digesting temperature is 265℃, the A/S of red mud is 0.88, and N/S is 0.5, the L/S of sedimentation red mud is3.0, and 2.5 of the washing red mud. the emphase of these is the design of the red mud washing workshop. A process containing five-time reversed washing is designed. Moreover, it’s heat loss is calculated. Meanwhile, the cost of the plant is also calculated, labor is organized in the seed precipitation workshop. Exact motheds of waste disposal are designed according to the possible pollution brought by the alumina production process. Final selection and plant layout, the main equipment in the plant configuration two diameter of 30m, 15m high separating setting tank, 5diameter of 26m, 15m high setting tank washing, 10 set of 3m high of 6m diameter hydraulic mixing tank, 5set of centrifugal pump, and setting tank fuondation, the entire device height of about 30m, The production area is about 312m long, width is about 108m, the area has a wide road, convention transportation and traffic of red mud.
Key words: alumina production; bayer process; gibbsite; leaching