The characteristics of the untreated and treated greywater and their related standards
| Characteristics . | Average concentrationa . | Standard recommendationb,c . | |
|---|---|---|---|
| Untreated GW . | Treated GW . | ||
| pH | 7.23 | 7.28 | 5.0–9.0b |
| Temperature (°C) | 26.26 | 24.65 | <3 °C from natural temperatureb |
| Dissolved oxygen, DO (mg/L) | 0.85 | 1.49 | 4.0b |
| Electric conductivity, EC (μS/cm) | 596.00 | 586.39 | – |
| Turbidity (NTU) | 38.57 | 18.2 | – |
| Chemical oxygen demand, COD (mg/L) | 29.74 | 9.95 | – |
| Biochemical oxygen demand, BOD (mg/L) | 106.99 | 35.63 | 2.0b |
| Total nitrogen, N (mg/L) | 18.98 | 14.75 | 5–30c |
| Total phosphorus, P (mg/L) | 0.330 | 0.339 | – |
| Total potassium, K (mg/L) | 1.06 | 1.07 | – |
| Total solids, TS (mg/L) | 408.98 | 353.70 | <500c |
| Total dissolved solids, TDS (mg/L) | 345.61 | 333.80 | <450c |
| Total suspended solids, TSS (mg/L) | 47.10 | 7.60 | <50c |
| Grease and oil (mg/L) | 20.24 | 3.30 | – |
| Organochlorine pesticides (mg/L) | ND | ND | 0.05b |
| Cadmium, Cd (mg/L) | 0.0005 | 0.0005 | 0.05b |
| Chromium, Cr (mg/L) | ND | ND | 0.05b |
| Copper, Cu (mg/L) | ND | ND | 0.1b |
| Lead, Pb (mg/L) | 0.002 | 0.001 | 0.05b |
| Zinc, Zn (mg/L) | 0.021 | 0.011 | 1.0b |
| Mercury, Hg (mg/L) | ND | ND | 0.002b |
| Arsenic, As (mg/L) | ND | ND | 0.01b |
| Total coliforms (MPN/100 mL) | 24,000 | 23,417 | 20,000b |
| Fecal coliforms (MPN/100 mL) | 6,132 | 5,666 | 4,000b Relaxed to <10,000 for high-growing leaf crops or drip irrigationc |
| Characteristics . | Average concentrationa . | Standard recommendationb,c . | |
|---|---|---|---|
| Untreated GW . | Treated GW . | ||
| pH | 7.23 | 7.28 | 5.0–9.0b |
| Temperature (°C) | 26.26 | 24.65 | <3 °C from natural temperatureb |
| Dissolved oxygen, DO (mg/L) | 0.85 | 1.49 | 4.0b |
| Electric conductivity, EC (μS/cm) | 596.00 | 586.39 | – |
| Turbidity (NTU) | 38.57 | 18.2 | – |
| Chemical oxygen demand, COD (mg/L) | 29.74 | 9.95 | – |
| Biochemical oxygen demand, BOD (mg/L) | 106.99 | 35.63 | 2.0b |
| Total nitrogen, N (mg/L) | 18.98 | 14.75 | 5–30c |
| Total phosphorus, P (mg/L) | 0.330 | 0.339 | – |
| Total potassium, K (mg/L) | 1.06 | 1.07 | – |
| Total solids, TS (mg/L) | 408.98 | 353.70 | <500c |
| Total dissolved solids, TDS (mg/L) | 345.61 | 333.80 | <450c |
| Total suspended solids, TSS (mg/L) | 47.10 | 7.60 | <50c |
| Grease and oil (mg/L) | 20.24 | 3.30 | – |
| Organochlorine pesticides (mg/L) | ND | ND | 0.05b |
| Cadmium, Cd (mg/L) | 0.0005 | 0.0005 | 0.05b |
| Chromium, Cr (mg/L) | ND | ND | 0.05b |
| Copper, Cu (mg/L) | ND | ND | 0.1b |
| Lead, Pb (mg/L) | 0.002 | 0.001 | 0.05b |
| Zinc, Zn (mg/L) | 0.021 | 0.011 | 1.0b |
| Mercury, Hg (mg/L) | ND | ND | 0.002b |
| Arsenic, As (mg/L) | ND | ND | 0.01b |
| Total coliforms (MPN/100 mL) | 24,000 | 23,417 | 20,000b |
| Fecal coliforms (MPN/100 mL) | 6,132 | 5,666 | 4,000b Relaxed to <10,000 for high-growing leaf crops or drip irrigationc |
ND, not detected.
aThe average concentration during 13 weeks of cultivation.
bThe standard of the surface water quality used for agriculture notified by the National Environmental Board of Thailand (1994).
cGuidelines for the Safe Use of Wastewater, Excreta, and Greywater (WHO 2006).