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Treatment of Filter Backwash

The ZeeWeed immersed ultrafiltration membrane is tolerant to high levels of solids in the process tank. This allows the membrane to treat filter backwash and efficiently reduce the volume of waste for disposal.

Typical Treatment Results

  • Turbidity < 0.1 NTU
  • Bacteria > 4 log removal
  • Giardia Cysts > 4 log removal
  • Cryptosporidium Oocysts > 4 log removal
  • Virus Rejection - ZeeWeed 1000 > 4 log
  • Virus Rejection - ZeeWeed 500 > 2.5 log
  • Total Suspended Solids < 1 mg/L
  • Total Organic Carbon - 50-90% removal
  • Color < 5 PCU
Feature Profile
Orangeburg Filter Backwash Recovery System

Orangeburg Filter Backwash Recovery System

The Orangeburg Filter Backwash Recovery System was designed to meet an initial plant capacity of 350 USgpm. It is a one train system with future expandability to two trains.

There are three water sources to be treated including filter backwash, rewash water and sedimentation basin solids. These three streams are directed to an existing equalization basin where a portion of the solids settle out and are pumped to the sanitary sewer. The settled water will be directed to the ZeeWeed process tanks. The concentration of total suspended solids (TSS) in the settled water is in the range of 2 - 400 mg/L. The system will operate at a volume recovery ratio of 90 - 95%. Therefore, depending on the operating recovery, the TSS in the concentrate (or reject from the ZeeWeed tank) will be in the range of 20 - 8000 mg/L. The concentrate from the ZeeWeed tank is either pumped back to the equalization basins at the head of the water treatment plant or directly to the sanitary sewer.