For some special material, while filtering, it might need cake washing. For plate filter press, normally adopts cross washing. But for belt filter, especially vacuum belt filter press, how to wash cakes? Popularly there are two methods:
As the name, the cake output will be washed by several sections. While belt filter press working, we can segment the cake area for different individual parts. Then wash them separately. The clear washing liquid will pass through a serrated overflow weir so that can be sprayed more evenly on top of the filter cake. When the filter cake is fully washed, we can appropriately increase the washing sections and amount, so as to get the best washing effect.
2.Countercurrent Washing / Back Washing:
In general, the use of counter - current washing can improve the cleaning efficiency. Popularly we divide the cake ares into three parts. First we use fresh washing liquid in final section. Then its discharge will be be used as the lotion in paragraph 2. Similarly, the filtration in paragraph 2 will also be used as the lotion in paragraph 1. The filtration in 1st part will be used as mother liquid. In this way, it can get a better washing result. This is also especially suitable for rich liquid, especially in mining industry.