Daxing Town Tap Water Project of Zhangjiagang City
The original water purification process of the water supply station of Daxing Wool Spinning Factory adopts: coagulation → sedimentation → sand filtration → water supply. Due to the small amount of water produced and the unstable water quality, the post-transformation process is: half-way coagulation → ceramic membrane filtration → water supply. After the transformation, the water treatment capacity of the water supply station is increased, the amount of chemicals is saved, the area occupied by structures is greatly reduced, and the water quality of the water is stable and up to standard. The main indexes of effluent are better than the standard limits of Sanitary Standard for Drinking Water (GB 5749-2022), Control Standard for Key Water Quality Indicators of Urban Waterworks in Jiangsu Province (DB32/T 3701-2019) and Suzhou Municipal Drinking Water Quality Index Limits (Su Shi Shui [2021] No. 376).
Suzhou drinking water quality index limits
Project |
Suzhou drinking water quality index limits |
Water quality of water supply station |
Total number of colonies (CFU/mL) |
50 |
Not Checked Out |
Total Coliform (MPN/100mL or CFU/mL) |
Not to be detected |
Not Checked Out |
Chroma (Platinum Cobalt Chroma Units) |
10 |
<5 |
Turbidity (Scattering Turbidity Unit)/(NTU) |
0.5 |
<0.1 |
stink and smell |
No odor or peculiar smell |
No odor or peculiar smell |
visible to the naked eye |
None |
None |
Permanganate index (in O2)/(mg/L) |
Water restrictions: 1.5, with the Yangtze River as the source of water |
1.04 |
Free chlorine (using chlorine and free chlorine determination at the time of preparation) |
Limit value of ex-factory water and pipe network terminal water/(mg/L)≤ 1.0; Remaining amount of pipe network water and terminal water of official website: ≥ 0.05; |
0.7 |
Aluminum (mg/L) |
0.15 |
0.015 |
Iron (mg/L) |
0.2 |
<0.03 |
Manganese (mg/L) |
0.05 |
<0.03 |
Nitrite (in N)/(mg/L) |
0.1 (free chlorine disinfection) |
<0.001 |