A company wants to process its washing water from two plastic shredder machines

A company develops industrial equipment such as shredders and compactors for the plastic recycling industry. In the field of its expertise, our Customer wants to treat the washing water coming from two separate plastic shredder machines. This process generates 1 to 3 tons of wastewater daily loaded with mineral residues, hydrocarbons, organic matter and fine plastic particles.

Several tons of wastewater from plastic pulverizer machines need to be treated and recycled

Our Customer is required to treat and recycle the washing water from two wet plastic granulator machines.

The first shredding line includes the washing of used non-food plastics and from the recycling of plastic waste, plastic jugs, bumper face-bars, and garden furniture. The capacity of the shredding line is 1 T/h. The wastewater is mainly polluted with suspended solids, organic matters and fine particles of shredded plastics.

The second shredding line consist of washing plastics from the automotive industry, such as bumper face-bars and plastic tanks. The capacity of the washed shredding line is 3 T/h.

Both shredding lines are collected to a common 32m3 wastewater pit for the recirculation of the washing water.

In the absence of a wastewater microstation treatment, our Customer would be obliged to have the wastewater pit pumped and emptied regularly by an external service provider.

A NISKAE wastewater microstation treatment was chosen to be able to collect and treat 3 000 to 4 000 L of wastewater daily in order to decrease the volume of water in circulation.

Limiting the frequency of emptying, improving the quality of the process water, limiting the fouling of the installation are all advantages of a NISKAE solution for the treatment and recycling of wastewater.

Multiple samples of washing water from crushing processes are tested by NISKAE experts

In order to able to offer a suitable and efficient process, NISKAE has done several coagulation and flocculation tests in the laboratory to provide a custom-made coagulant-flocculant. The wastewater treatment reagent is used at a dosage of 3 g/L with a reduced reaction time.

Our specific and adapted formulation has reduced the initial iron concentration from 141.30 mg/L to less than 1.12 mg/L. The appearance of the washing water before treatment was black but is now clean and translucent. The water is now reusable and can be re-injected into the shredding process.

A SW500 station works in combination with the use of the specific reagent for the treatment

In light of the tests and analysis carried out previously, the NISKAE team recommends the installation of a SW500 microstation with a 500 L treatment batch. This wastewater microstation is automatic, fast and easy to use. Moreover, it is equipped with all the safety equipment required for a safe industrial operation.

The proposed SW500 installation includes,1 pneumatic pump to transfer the water from the recovery pit to the treatment plant ;
  • 1 SW500 wastewater treatment reactor with a capacity of 500 L allows the separation by coagulation and flocculation of the wastewater in a few minutes ;
  • 1 powder dosing unit guarantees the automatic addition of the flocculating reagent;
  • 2 mobile filtration carts ensure the storage and the dehydration of the sludge.

A cost-effective investment for our Client and the environment

The new SW500 station now allows our customer to reduce maintenance costs and ensures simplified logistics. To date, our customer has been able to reduce the frequency of emptying the wastewater pit and maintain an acceptable water quality to avoid premature fouling of the process.