Complaint
| Items | Permissible Value | Probably Consequence of Excessive Standard | Improvement Suggestions | |
| Suspended solids | Tubidity | <1NTU | Sludge ,colloid pollution | Flocculation and filtration |
| SDI15 | <5 | |||
| Metal oxides | Fe ( mg/L) | <0.05 | Iron Pollution | Oxidation precipitation/filtration |
| Mn (mg/L) | <0.05 | |||
| Scale forming matter | CaCO3 | LSI<0 | Concentrated water side does not permit scaling | Decrease recovery rate , PH value , or add scale inhibitor |
| Other insoluble salt | / | |||
| Organics | Oil | 0 | Organics and oil | Air |
| TOC (mg/L) | <10 | Organics pollution | Activated carbon adsorption , filtration | |
| CODcr (mg/L) | <10 | |||
| BOD5 (mg/L) | <5 | |||
| Si (mg/L) | <20 | Colloid pollution | ||
| PH | 3-10 | Too low or too high PH will accelerate the aging speed of membrane | Regulation of Acid-base | |
| Temperature | 5-45°C | Low temperature will easily produce scaling of undissolved salt High temperature will accelerate the aging speed of membrane | Heat exhanger | |
| Oxidizer | Residual chlorine (mg/L) | <0.1 | Membrane system will be oxidized | Reductant or aclivated carbon adsorption |
| Ozone and others | 0 | |||
