Texas City Ends Permit Limit Infringements With One Simple Solution

The Problem: The Southside WWTP in Tyler, Texas, is a multi-train activated sludge plant that in recent years had seen sporadic effluent quality as a result of aeration limitations in the biological processes. These limitations were compounded by low and unstable pH and insufficient influent alkalinity. On top of that, Tyler’s recently commissioned water plant occasionally sends low pH solids and process water to the Southside WWTP.

These uncontrollable processes lead to intermittent permit limit infringement and a significant potential for permit violations.

Caustic soda was used with limited success to supply much-needed alkalinity and raise pH. However, tremendous care was required to prevent pH “spiking” and the amount of alkalinity supplied with these spiking limitations was marginal, at best.

The Solution: Thioguard TST, which is nonhazardous, non-pharmaceutical, technical-grade milk of magnesia for use in municipal wastewater treatment. The properties of milk of magnesia allowed Tyler personnel the ability to supply significantly more alkalinity in a biologically reactive form, while shifting the pH into a bio-optimal range without the spikes. Additionally, Thioguard added divalent cations, improving the M/D ratio.

The Result: Once on Thioguard and through a fully activated sludge age cycle, effluent BOD, TSS and NH3 numbers dropped to better than expected levels (well below permit limits) and remained level. The City of Tyler has used Thioguard continuously ever since, allowing them to withstand random influent quality swings and aeration system upsets.

Download the case study to view graphs depicting data six months prior to the start of Thioguard use, and six months with Thioguard use.

For more information on Thiguard, visit thioguard.com.