Assessment of Phosphorus Recovery from Swine Wastewater in Beijing, China
The nutrient management of phosphorus (P) contained in swine wastewater is an important challenge to enhance P use efficiency. In the present study, assessment of P recovery from swine wastewater in Beijing was performed. P amounts of swine wastewater increased from 11,687 tons in 1980 to 16,237 tons in 2014. Without treatment of swine wastewater, P concentration will reach a maximum 1.20 mg/L. The maximum P recovery was 99.36% under the condition of crystallization coupled BPR (biological
... PR (biological phosphorus removal) when the operating conditions were 60.6 mg/L for C p (initial P concentration (mg/L)), 1.2 for Mg/P (magnesium-to-P molar ratio), 9.7 for pH of crystallization process, and 8.0 for pH, 1.6 h for anaerobic stage time, 15 days for sludge retention time of BPR. The P concentration for water quality was 0.03 mg/L to meet the water regulation standard. Under this situation, if the target P concentration were set as Grade II and III, pig breeding numbers reached 42.07 and 95.90 million heads. Construction investments for the crystallization, BRP, and coupled methods are 411 (10 4 Yuan, 604,307 USD), 301 (10 4 Yuan, 442,580 USD), and 551 (10 4 Yuan, 810,170 USD), respectively. The running costs are 15.205 (10 4 Yuan/year, 22,360 USD/year), 28.907 (10 4 Yuan/year, 42,500 USD/year) and 44.112 (10 4 Yuan/year, 64,860 USD/year). To manage non-point pollution, swine wastewater treatment facilities should be used and pig breeding numbers should be managed within reasonable ranges.