Description
Poly aluminum chloride (PAC) is a widely used water treatment
chemical, known for its effectiveness in coagulation and
flocculation processes. It is a type of aluminum-based coagulant
commonly used in water purification and wastewater treatment.
### **Characteristics:**
- **Chemical Formula:** The general formula for poly aluminum
chloride is [(Aln(OH)mCl(3n-m))], where "n" and "m" vary depending
on the specific product and formulation.
- **Appearance:** PAC typically appears as a white to yellowish
powder or a clear to pale yellow liquid.
- **Solubility:** It is highly soluble in water, forming a solution
that is used in various treatment processes.
### **Uses:**
1. **Water Treatment:**
- **Coagulation and Flocculation:** PAC is used to
remove suspended solids and impurities from water. It helps to form
flocs, which are aggregates of particles that can be easily removed
from the water.
- **Drinking Water:** Used in municipal drinking water
treatment plants to ensure water meets safety standards for
consumption.
- **Wastewater Treatment:** Employed in the treatment
of industrial and municipal wastewater to remove contaminants and
facilitate the subsequent processes of filtration and
disinfection.
2. **Industrial Processes:**
- **Paper Manufacturing:** PAC is used in the paper
industry to improve the efficiency of the paper production process
by enhancing the retention of fillers and fibers.
- **Textile Industry:** Applied in the textile
industry for dyeing and printing processes to improve color
fastness and fabric quality.
3. **Soil Stabilization:**
- **Construction:** Used in construction and soil
stabilization to improve the strength and stability of soil.
### **Benefits:**
- **High Efficiency:** PAC is effective at lower doses compared to
other coagulants, reducing the amount of chemical needed and
minimizing the generation of sludge.
- **Versatility:** It works over a wide range of pH levels and can
handle various types of water sources, including those with high
turbidity.
### **Health and Safety:**
- **Handling:** PAC is generally safe to handle, but exposure to
the powder or concentrated solutions should be minimized. Use
personal protective equipment (PPE) such as gloves, goggles, and
masks if handling the dry form.
- **Storage:** Store in a cool, dry place, away from direct
sunlight and incompatible substances. Ensure containers are sealed
to prevent contamination and moisture absorption.
- **Environmental Impact:** PAC should be used in accordance with
local regulations to minimize any potential environmental impact,
particularly regarding residual chemicals in treated water.
### **Environmental Considerations:**
- **Residuals:** The use of PAC in water treatment can result in
residual aluminum in the treated water. While aluminum levels are
typically monitored to ensure they are within safe limits, it is
important to adhere to guidelines to avoid any potential
environmental or health issues.
### **Summary:**
Poly aluminum chloride (PAC) is an effective and versatile
coagulant used primarily in water and wastewater treatment to
remove impurities and enhance water quality. Its high efficiency
and ability to function across various pH levels make it a valuable
chemical in both municipal and industrial applications. Proper
handling and adherence to safety and environmental guidelines
ensure its effective and responsible use.
