pH Adjustment Systems

pH Neutralization / pH Adjustment Systems for industrial wastewater treatment 

Mail 64 2008

Treating a Waste Stream Laden
with HF Acid and Heavy Solids

Some industrial process problems are more demanding than others. The above two photos illustrate Wastech's solution to a complex challenge.

The customer's problem. This customer has a waste stream with HF acid and heavy solids, and demanded that the system be completely automated in an enclosed room for safety reasons. The solid loading was a particular problem. The acid must be neutralized in the first step. The second step is the addition of polymer, and the third step is the separation of the solids using high capacity 17-bag filter housings.

Wastech's solution. The HF neutralization skid is double-contained with a reinforced PP skid and 3/4" PP walls for containment. A holding tank continually receives liquid from the process, which is then pumped to a small reaction tank where the HF acid is batch-neutralized. The holding tank is continually mixed to keep the solids in suspension. Both tanks are cone-bottomed PE with welded PE legs for corrosion resistance. The small reaction tank is also a cone-bottomed PE tank with a circulation pump and mixer. The circulation pump with pneumatic actuated valves also acts as a discharge pump once the batch is neutralized.

Each neutralized batch is sent to the Filtration Preparation Skid, where another holding tank keeps the solids in suspension until a batch is released to the polymer mixing tank. Polymer is dosed inline with water through an efficient in-line mixer to "unfold" the polymer. This design eliminates the need for an expensive polymer blending unit. The mixing tank has a two speed mixer and once the polymer is reacting with the liquid it is sent to the final skid with the high capacity multi-bag filter housing. These 17-bag filters will handle an 8-hour shift without maintenance.

The entire system is automated with multi-PLCs and interconnected HMI screens. Alarm management and communications are also included.

When the process is complex and requires a complete solution, Wastech engineers are there to develop the right system. Wastech's solution will be reliable and automated for predictable service and performance.

For Assistance with Acid Neutralization

Call us at 818-998-3500 for assistance and a quotation.

  • Ben Naylor – Application Engineer (ext 227)
  • Harold Sipe – Senior Application Engineer (ext 224)