Phosphorus removal in wastewater is an important aspect of operating municipal and industrial waste treatment plants. Regulatory agencies often require removal of 90% of the incoming phosphorus to a treatment plant and may also require a P concentration of no more than 1 mg/L (ppm) in plant effluent, particularly when treated wastewater is discharged to a small stream, lake or wetlands.
High levels of phosphorus and other nutrients, such as nitrogen, can create harmful water quality conditions. The result may be algae blooms, excessive weed growth, and oxygen depletion in streams, lakes, rivers, and other bodies of water.
Nutrient loading began to garner attention in the late 1960’s and early 1970’s. Phosphorous pollution comes from fertilizing farm lands, household detergents, residential septic tanks, municipal wastewater treatment plant runoff, and residential lawn fertilizers. Additionally, harmful phosphorous can come from storm water runoff, outdated sewage and septic systems, trash and wildlife.
Over the years, two effective control methods to reduce phosphorus have been implemented. The first included legislation to ban phosphate in laundry detergents. The other is the upgrading of municipal wastewater treatment plants.
USALCO sodium aluminate (LSA 38) is highly effective for phosphorous control in wastewater treatment plants where discharge limits are set by federal, state, or local regulations. LSA 38 contains the highest concentration of metal ions to sequester and control the problem. Sodium aluminate outperforms alum, ferric chloride, and ferrous chloride at lower overall cost. Unlike these acidic chemicals, Sodium Aluminate will not deplete available alkalinity and depress effluent pH below discharge limits.
LSA 38 has been proven to solve problems, add value, and provide cost savings when converting from alum, ferric chloride or ferrous chloride. The benefits are:
- Gallons per day chemical requirement reduced by 50 to 80%.
- Reduction or elimination use of chemicals for pH adjustment, such as sodium hydroxide and lime.
- Elimination of negative interference in UV systems where iron was previously utilized, thereby improving energy efficiency.
- Improvement of ammonia removal and compliance in systems with deficient or depleted alkalinity.
- Year round consistent control, unlike competitive chemicals whose performance diminishes outside certain pH and or alkalinity ranges.
LSA 38 Phosphorus Removal Application Guide
Comparison of Phosphorus Removal Chemicals
Case Study #1 – solving alum performance problem
Case Study #2 – restoring compliance and reducing cost
Case Study#3 – replacing ferrous chloride eliminates metals contamination and associated cost
