| |
Direct addition of THIOGUARD® to a collection system provides the following benefits at the Treatment Plant:
Odor Control
Corrosion Control
Nutrient Addition — Essential Element for Cell Metabolism
Alkalinity Supplementation
pH Control |
 |
THIOGUARD® improves secondary wastewater treatment for BOD (Biological Oxygen Demand), TSS, Turbidity, ammonia and phosphorus, while enhancing sludge growth and settling characteristics, and improving biosolids treatment, dewatering and disposal.
Nitrogen compounds are the primary cause of pH/alkalinity degradation in treatment plants, with pH depletion being the major cause of activated sludge bulking, high SVI (Sludge Volume Index), and disinfection problems.
Digestion, Nitrification, Alkalinity and pH Control
Aerobic digestion and nitrification in the activated sludge process depletes natural alkalinity and can cause pH depression. A drop in pH can arrest second-stage nitrification and cause major upset conditions in the secondary clarifiers, resulting in effluent violations for BOD, TSS (Total Suspended Solids), ammonia, etc...Likewise, adequate alkalinity insures biological process stability and improves methane gas production of anaerobic digesters. THIOGUARD® provides both alkalinity and pH stability for biological processes.
Secondary Clarifiers and SVI
Periodic pH problems interfere with the growth of floc-forming activated sludge. When this happens, sludge bulking and unwanted denitrification may cause SVI levels to increase. THIOGUARD® provides both pH stability and divalent cations, which improve the Monovalent/Divalent (M/D) Cation Ratio.
Biosolids
These divalent cations and pH stability provided by THIOGUARD® also improves dewatering/drying performance, polymer use and odor reduction, whether using drying beds, filters, or centrifuges.
Chlorine Disinfection
Incomplete nitrification allows nitrite (NO2-N) to pass through the clarifiers and into the chlorine contact tank, consuming chlorine at accelerated rates. Moreover, low pH and inadequate alkalinity can hinder rapid hydrolysis of Cl2 gas, reducing disinfection efficiency. THIOGUARD® facilitates complete nitrification and provides pH stability for efficient chlorination.
pH Control
Magnesium hydroxide slurry has long been used to maintain pH during nitrification. Because alkalinity is released slowly, there are no hot spots to kill Nitrosomonas or Nitrobacter bacteria.
And since the by-products of magnesium hydroxide reactions are soluble salts, THIOGUARD® does not increase the amount of sludge produce in the plant. In fact, studies have shown THIOGUARD® may actually reduce sludge production by 10-20%.
. |
