There are also some precautions of the plastic crushing and washing, because of the different of plastic type, the processes of the plastic plastic are mainly separated to two types--hard material and soft material. Their washing and cleaning methed and equipment are certainly different.
In one hand, the crusher of soft material and hard material are different. Specifically, their blades are different. In the other hand, in the duration of the cleaning, the soft material like plastic woven bags are always floating on the surface of the water, we call them "flaoting material", the hard plastic like PP flakes always sink under the water, we call them "sinking material".
Generally speaking, the hard plastics are cleaner and use less water, so they do not need a sedimentation tank. (Sedimentation tank can pumped out and reused after the sewage has settled, which will greatly save water.) However, the floating materials are very dirty, they have much floating ash on them and the demand of water is high.
Nowadays, many countries make a prohibition of sewage discharge, so make a sedimentation tank and mud filtering equipmenr, then the water can basically meet the national standards.