Collaborative Innovation Mechanism of Water Pollution Control Industry Chain Based on Complex Scientific Management

Table 1

Water quality index classification standard.

Grade	Total phosphorus purification rate (%)	Purification rate of ammonia nitrogen content (%)
I	0–5	0–10
II	6–15	11–25
III	16–20	26–35
IV	21–40	36–45
V	41–100	46–100