Effluent Treatment Plant
Corrotech Effluent Treatment Plant is designed to treat spent acid and wash water combined. The system aims to control the pH, iron content, total suspended solids, oil, grease, chemical oxygen demand (COD), biological oxygen demand (BOD).
The spent acid generated from hot dip galvanizing process contains the below contaminants
- Oil & Grease:
It is generated during the degreasing of surface of metal which are to be galvanized.
It is generated during the pickling process with dil. Hydrochloric acid due to the removal of scales and rust.
- COD & BOD:
It is generated during the degreasing operation and contaminants from diluted hydrochloric acid.
It is generated during the floor washing / spillages from fluxing operation.
- Acidic pH:
It is generated during the washing process after pickling operation.
Corrotech Design of ETP
Effluent Treatment Plant
Key characteristics of spent acid considered in designing ETP include flow, and physical, chemical, and biological characteristics of the spent acid. Spent acid flow, commonly expressed as m3 /day, determines the size of the ETP. Minimum and maximum flow rates are estimated as precisely as possible because they affect hydraulic computations and sizing of channels and distribution pipes. Design flows also incorporate anticipated future increases. Large temporal flow variations (e.g., diurnal fluctuations, inflow/infiltration response to rainfall) are built in through use of equalization ponds or tanks to allow a constant or nearly constant flow rate through the downstream treatment processes. Another benefit of equalization ponds is to reduce the effect of toxic shock on treatment processes caused by accidental releases of toxic substances. This reduction is accomplished by blending spent acid with lower concentrations in the equalization basin. Significant physical characteristics include solids, temperature, color, and odor. Solids in the form of floating debris and grease and oil slicks indicate a highly polluted waste stream and indicate untreated or ineffectively treated wastes. Suspended solids contribute to turbidity and silt load and are removed through sedimentation or filtration. Spent acid temperature is an important parameter because it affects chemical and biological reactions and the solubility of gases such as oxygen. Generally, higher temperatures increase reaction rates and solubility up to the point where temperature becomes high enough to inhibit the activity of most microorganisms (around 35¬C). Color and odor serve as indicators of the degree of pollution of a waste stream, and their presence in spent acid indicates inadequate pretreatment prior to discharge
Key Features of Corrotech Effluent Treatment Plant
- ETP is designed to handle spent acid and acid rinse
- State of the art – modern technology for neutralization
- Lower power consumption
- No manual chemical dosing system
- Entire spillages are collected in ETP
- Ensures no spillages on the earth
- Polyelectrolyte used ensures better separation of solid and liquid
- Ensures complete removal of iron in post aeration
- Two stage oil separator ensures complete removal of oil and grease
- Sludge stored in secured landfill
- Treated effluent meets complete standards prescribed by CECB
- Treated effluent is used for tree plantation/gardening
- Gardening near the ETP area ensures proper O&M of ETP
Corrotech ETP contains the below systems
- Bar Screen
- Oil Separators
- Receiving Sump
- Collection cum Reaction Tanks
- Post Aeration Tank
- Collection Tanks
- Effluent Transfer Pumps
- Filter Press Feed Pump
- Filter Press
- DMF Feed Pumps
- Dual Media Filter