Table 1: Physico-chemical and heavy metals analysis of Cocoa processing industry wastewater.
Parameter | Cocoa processing wastewater | USEPAa | NESREAb |
---|---|---|---|
Colour | Dark brown | Colourless | - |
pH | 7 | 6.5-8.5 | 6-9 |
EC | 290 | - | - |
COD | 303 | 410 | 90 |
BOD | 222 | 250 | 50 |
TDS | 580 | 500 | 500 |
Alkalinity | 62 | 20 | 150 |
Acidity | 9 | - | - |
Chloride | 20 | 250 | 250 |
Ammonia | 1.2 | 0.03 | 1 |
Phosphates | 0.04 | 5 | 2 |
Nitrates | 1.20 | 10 | 10 |
Sulphate | 1.69 | - | - |
Lead | 0.9 | 0.015 | 0.05 |
Cadmium | 0.14 | 0.005 | 0.2 |
Chromium | 1.00 | 0.1 | 0.05 |
Copper | 2.32 | 1.3 | 0.5 |
Iron | 1.40 | 0.3 | 0.30 |
Manganese | 0.81 | 0.05 | 0.2 |
Nickel | 0.41 | - | 0.01 |
Zinc | 10.2 | 5 | 5.00 |
NESREAa: National Environmental Standards and Regulation Enforcement Agency (2009); USEPAb: United States Environmental Protection Agency (2009); BODc: Biochemical Oxygen Demand; CODd: Chemical Oxygen Demand; TDSe: Total Dissolved Solid; EC: Electrical Conductivity. Units of the parameters are in mg/L except for pH which has no unit and EC in μScm-1.