College of Natural Resources and Environment, South China Agricultural University, Guangzhou 510642, China; Guangdong Provincial Key Laboratory of Agricultural & Rural Pollution Abatement and Environmental Safety, Guangzhou 510642, China.
College of Natural Resources and Environment, South China Agricultural University, Guangzhou 510642, China; Guangdong Provincial Key Laboratory of Agricultural & Rural Pollution Abatement and Environmental Safety, Guangzhou 510642, China.
Sci Total Environ. 2023 Jul 10;881:163315. doi: 10.1016/j.scitotenv.2023.163315. Epub 2023 Apr 5.
Biochar adsorption materials have a good removal effect on ammonia nitrogen in piggery biogas slurry. However, the cost of biochar adsorption material is still high. If these materials can be recycled several times, the cost can be significantly reduced. Therefore, this paper investigated a new process of biochar adsorption material (C@Mg-P) pyrolysis cycle for reducing ammonia nitrogen in piggery biogas slurry. The effects of pyrolysis process conditions (pyrolysis temperature and pyrolysis time) and number of recycling times on reducing ammonia nitrogen in biogas slurry by C@Mg-P were studied, a preliminary investigation on the reaction mechanism of C@Mg-P for reducing ammonia nitrogen in biogas slurry was conducted, and the economic feasibility of the pyrolysis recycling process was analyzed. It was found that the NH-N elimination efficiency by C@Mg-P was 79.16 % under the optimal conditions of 0.5 h and 100 °C. Second, C@Mg-P removed 70.31 % NH-N after recycling 10 times. Chemical precipitation, ion exchange, physical adsorption and electrostatic attraction were the potential reaction mechanisms for NH-N reduction by C@Mg-P. Moreover, C@Mg-P had a good decolorization effect on piggery biogas slurry with a 72.56 % decolorization rate. Compared with the non-pyrolyzed recycling process, the proposed process saved 80 % of the cost, thus representing an economically possible approach for pig manure biochar application in wastewater denitrification treatment.
生物炭吸附材料对猪场沼气液中的氨氮具有良好的去除效果。然而，生物炭吸附材料的成本仍然很高。如果这些材料可以多次回收利用，成本可以显著降低。因此，本文研究了一种新的生物炭吸附材料（C@Mg-P）热解循环工艺，用于降低猪场沼气液中的氨氮。研究了热解工艺条件（热解温度和热解时间）和循环次数对 C@Mg-P 降低沼气液中氨氮的影响，初步探讨了 C@Mg-P 降低沼气液中氨氮的反应机制，并分析了热解循环工艺的经济可行性。结果表明，在 0.5 h 和 100°C 的最佳条件下，C@Mg-P 的 NH-N 去除效率为 79.16%。其次，C@Mg-P 经过 10 次循环后，去除了 70.31%的 NH-N。化学沉淀、离子交换、物理吸附和静电吸引是 C@Mg-P 还原 NH-N 的潜在反应机制。此外，C@Mg-P 对猪场沼气液具有良好的脱色效果，脱色率为 72.56%。与未热解的回收工艺相比，该工艺节省了 80%的成本，因此代表了一种在废水脱氮处理中应用猪粪生物炭的经济可行方法。
