chemistry with your wastewater products:
- Optimize chemistry to meet your local discharge requirements
- Meet industry-specific contaminants discharge limits
- Reduce the amount of sludge produced
- Reduce the amount of chemicals used
- Reduce the amount of transportation required to get that chemistry on the site
- Reduce your environmental footprint
- Reduce your costs
WHAT’S THE COAGULATION FLOCCULATION PROCESS?
Coagulation is the process in which particle destabilization is achieved. By introducing a coagulant, negatively electrically charged particles in the water are neutralized, allowing the floc to come out of suspension and create what is often referred to as the Pin-floc. Coagulation is achieved with 2 types of coagulants, Organic and or inorganic coagulants. Inorganic coagulants introduce a cationic charge to the solution through metal salts such as iron and aluminium based coagulants. Organic coagulants do the same with compounds such as PolyDADmacs, polyamines and tannins. Coagulants can be chosen to fit your specific application. Through jar-testing and optimization of both coagulation and flocculation, it is possible to dramatically affect the performance of your waste-water system.
Flocculation is achieved with polymers or polyelectrolytes. The goal of flocculation is to agglomerate the pin-floc into larger size particles to increase the efficiency of removal through settling or flotation. Polymers come in many charge concentrations as well as molecular weight.Through jar-testing and optimization of both coagulation and flocculation, it is possible to dramatically affect the performance of your waste-water system.
REAL WORLD ANALYSIS & CASE STUDIES
A wastewater treatment manager from a cheese processing plant called Aquasan to optimize dosages and methodology of treatment. The plant is a combination of Physico-chemical treatment followed by a biological treatment. Upon preliminary assessment, it was noticed that the system was showing signs of chemical overdose.
Through a series of jar-testing on the client sites, it was determined that the system did have room for chemistry optimization and redesign. Through a change in coagulant and as well as in charge density and molecular weight for the polymer, jar-tests yielded a possible reduction of 50% in chemical consumption.Aquasan’s team led a plant trial to verify and optimize the proposed solution. A plant trial allows us to verify that the economy in chemicals can be transferred onto the client’s equipment without negatively impacting the quality of discharged water.
An overall reduction of 60% of chemical consumption was achieved. This also led to :
- A reduction of chemical manipulation for operators.
- A reduction from weekly deliveries to monthly deliveries.
- Reduction of sludge production by more than 50%
- 43% in cost savings.
- Reduction of environmental footprint with choice of chemistry, delivery frequency and sludge production
- Increase in the stability of treatment.
- Decrease in loading pressure on the biological system.
- Decrease in load pressure on the dosing equipment.
- After a year of optimization, overall yearly chemical expenditure was reduced by 66%.
A design engineer from an equipment manufacturer who had received the mandate to install a DAF (Dissolved air flotation unit) for a municipal pre-treatment plant mainly treating slaughterhouse effluent called on us to estimate the coagulant consumption of the future plant without us having any wastewater at our disposal to carry out tests. We established this by calculating the dosages of the imposed coagulant (ferric sulphate) according to the theory (chemical reduction of Phosphorus with iron salt).
Once the plant was built, unfortunately the consultant did not take into account our recommendations for adding an alkaline product such as caustic soda to compensate for the decrease in pH resulting from the addition of ferric sulfate (coagulant). Adaptation of the chemical solution according to the design of the plant by recommending another coagulant, an already pre-hydrolyzed aluminum-based coagulant which had the advantage of consuming very little alkalinity compared to the ferric sulfate initially planned. This coagulant had little effect on the pH of the treated water (slight acidification).
The chosen chemical solution allowed both:
- to comply with sewer discharge standards (pH, Phosphorus, Oils and Fats, Chemical Oxygen Demand)
- reduce the quantity and number of chemicals needed
- to be safer for operators since this aluminum-based coagulant is not considered hazardous (unlike ferric sulphate and caustic soda)
- to respect the client's budget since the recommended chemical solution was less expensive than that initially planned (ferric sulphate + caustic soda)