Surface World April 2019 Surface World April 2019 - Page 48

WATER & EFFLUENT TREATMENT pH Neutralisation System Many industrial processes produce effluent which is either too acidic or too alkaline to be safely discharged to drain, a piece of process control plant which is intercepts this and corrects the pH to make it safe to discharge to drain is called a pH neutralisation system. Since our foundation in 1982 we’ve supplied equipment and systems specifically for the pH neutralisation of waste water from industrial processes. Working with a market leading supplier in the surface finishing sector we were approached to design, build and commission a pH neutralisation system. Our customer is one of the leading providers of surface finishing solutions into the marine, rail and architectural sectors. As our customer is a supplier of numerous services, the waste- water treatment system will in turn be neutralising the pH from numerous processes, which include:- Galvanising Chemical pre-treatment Plant & Factory De-ionised water regeneration Multi-stage coarse & fine rinse water Principle Of Operation commissioning visit from one of our service engineers - our customer went ahead with this, which included:- A commissioning visit from our service engineers to ensure that the pH neutralisation system is calibrated and working in the manner specified by the customer. The waste-water to be pH corrected is transferred to the correction tank using air operated double diaphragm pumps. Using a series of level controllers and sump mounted low level float switches the control panel calls for the solenoid valves. These in turn control the incoming air flow to the pneumatically operated double diaphragm pumps which transfer the waste-water to the mixing tank. The pH electrode mounted inside the mixing tank works with the pH controller to call for either the acid dosing pump or alkaline dosing pump to neutralise the pH in the waste-water. The addition of the top mounted high mixer improves the efficiency of the chemical reagent reducing the required contact time for neutralisation. The system has been designed to neutralise the pH of our customers effluent making it compliant with the local legislation and By carefully calculating the contact time adhering to their consent to discharge required at the extremes of the incoming pH agreement. With the waste water from each scale the volume was calculated to ensure of the customers industrial processes, including waste pH Neutralisation System water from the rinses, the regeneration of the de-ionised water beds and the pre- treatment baths - all being collected into an underground sump. Our customer specified that the pH neutralisation system should be skid mounted to make sure that it can be easily moved to the desired location. All the systems that AWE supply, including the system for our customer are supplied:- Complete with a full suite of technical drawings to make mechanical integration as simple as possible. Ready, wired and tested to ensure that the onsite electrical engineers can quickly and easily bring the system into operation. When purchasing a system from AWE we offer our customers an optional CONTINUED ON PAGE 50 46 APRIL 2019 twitter: @surfaceworldmag