Effects of initial carbon-phosphorus ratio on phosphatase, and phosphorus availability in sludge composting

Phosphorus in wastewater sludge is one of the important nutrients for biological growth and an important nonrenewable resource. Most research in the composting field focuses on the C/N ratio, but there are few reports on initial carbon-phosphorus (C/P) ratio regulation. This study investigated the effects of different initial C/P ratios on phosphatase activity, key bacteria, and phosphorus availability in compost. In this study, the activity of phosphatase was measured, and key bacteria secreting phosphatase were identified. The results showed that adjusting the initial C/P ratio could prolong the cycle of action of key bacteria, thus affecting the activity of phosphatase and promoting the production of available phosphorus, but it was also inhibited by the feedback of available phosphorus. This study demonstrated the feasibility of adjusting the initial C/P ratio of sludge composting and provided theoretical support for optimizing the application of sludge composting products with different initial C/P ratios.

Automated summary

This study investigated the effects of different initial C/P ratios on phosphatase activity, key bacteria, and phosphorus availability in compost. The results showed that adjusting the initial C/P ratio could affect the activity of phosphatase and promote the production of available phosphorus, but it was also inhibited by the feedback of available phosphorus. This study demonstrated the feasibility of adjusting the initial C/P ratio of sludge composting and provided theoretical support for optimizing the application of sludge composting products with different initial C/P ratios.