The feasibility and performance of nitrogen removal from municipal sewage were investigated through the completely autotrophic nitrogen removal over nitrite (CANON) process in a continuous reactor. CANON process was s...The feasibility and performance of nitrogen removal from municipal sewage were investigated through the completely autotrophic nitrogen removal over nitrite (CANON) process in a continuous reactor. CANON process was successfully started up with the transformation of nitrogen into gas by mass-balance analysis. For the synthetic waste-water (up to 480 mg NH4+-N/(L·d)), removal rates of the ammonia nitrogen and total nitrogen (TN) were about 80% and 55%, respectively, at 1.25 h hydraulic retention time (HRT). For the secondary effluent of municipal sewage, the effluent concentrations of NH4+-N and TN were below 5 mg/L and 9 mg/L, respectively. It is in accordance with the water quality standard for scenic environment with the reuse of urban recycling water (GB/T 18921-2002).展开更多
Two experiments were conducted to determine the effects of L y s ine（Lys） and Net Energy （NE） levels on growth performance （Exp. I） and N balance （Exp. 2） in growing pig. In Exp. 1, 36 castrated pigs [21.35 -4...Two experiments were conducted to determine the effects of L y s ine（Lys） and Net Energy （NE） levels on growth performance （Exp. I） and N balance （Exp. 2） in growing pig. In Exp. 1, 36 castrated pigs [21.35 -4- 0.55 kg of body weight （BW）] were allotted to six treatments with six replicates per treatment. Pigs were fed two levels of Lys （low and high） and three levels of NE （low, med, or high） in a 2×3 factorial arrangement. The experiment lasted for 35 d. There were no effects of dietary Lys and NE on pig performance （P〉0.05, but a Lys×NE interaction in ADG was observed （P〈0.05）. In Exp. 2, 24 pigs were used to determine the effects of diet in Exp. 1 on pig N balance. Neither Lys nor NE level affected N retention （g/d） （P〉0.0）. Lys×NE interaction in N retention （g/d） （P〈0.01） and in N apparent biological value （ABV） （P〈0.05） was observed. Pigs fed the low Lys diet had lower serum urea nitrogen （SUN） concentrations compared with the high Lys treatment （P〈0.01）. Pigs fed the med-NE diet had lower SUN concentrations compared with the pigs fed the low-NE diet （P〈0.1）. These results suggest that pigs from 21 kg to 50 kg BW fed diets containing 0.83% standardized ileal digestible Lysine and 2351 Kcal of NE/kg had maximum ADG and N retention.展开更多
基金Supported by National Natural Science Foundation of China (No. 50308012 and No.21107053)National Science & Technology Program of China (No.2012ZX07501002)
文摘The feasibility and performance of nitrogen removal from municipal sewage were investigated through the completely autotrophic nitrogen removal over nitrite (CANON) process in a continuous reactor. CANON process was successfully started up with the transformation of nitrogen into gas by mass-balance analysis. For the synthetic waste-water (up to 480 mg NH4+-N/(L·d)), removal rates of the ammonia nitrogen and total nitrogen (TN) were about 80% and 55%, respectively, at 1.25 h hydraulic retention time (HRT). For the secondary effluent of municipal sewage, the effluent concentrations of NH4+-N and TN were below 5 mg/L and 9 mg/L, respectively. It is in accordance with the water quality standard for scenic environment with the reuse of urban recycling water (GB/T 18921-2002).
文摘Two experiments were conducted to determine the effects of L y s ine（Lys） and Net Energy （NE） levels on growth performance （Exp. I） and N balance （Exp. 2） in growing pig. In Exp. 1, 36 castrated pigs [21.35 -4- 0.55 kg of body weight （BW）] were allotted to six treatments with six replicates per treatment. Pigs were fed two levels of Lys （low and high） and three levels of NE （low, med, or high） in a 2×3 factorial arrangement. The experiment lasted for 35 d. There were no effects of dietary Lys and NE on pig performance （P〉0.05, but a Lys×NE interaction in ADG was observed （P〈0.05）. In Exp. 2, 24 pigs were used to determine the effects of diet in Exp. 1 on pig N balance. Neither Lys nor NE level affected N retention （g/d） （P〉0.0）. Lys×NE interaction in N retention （g/d） （P〈0.01） and in N apparent biological value （ABV） （P〈0.05） was observed. Pigs fed the low Lys diet had lower serum urea nitrogen （SUN） concentrations compared with the high Lys treatment （P〈0.01）. Pigs fed the med-NE diet had lower SUN concentrations compared with the pigs fed the low-NE diet （P〈0.1）. These results suggest that pigs from 21 kg to 50 kg BW fed diets containing 0.83% standardized ileal digestible Lysine and 2351 Kcal of NE/kg had maximum ADG and N retention.
