尽管厌氧消化是处理食物垃圾(FW)的主流技术,由此产生的食物垃圾厌氧消化物(FWAD)中的高污染物浓度通常对随后的生化处理(如活性污泥法)提出挑战。在这项研究中,以典型的FW处理厂为例,我们分析了处理FWAD困难背后的原因,并测试了一种称为生物调理脱水的新工艺,然后是活性污泥法(BDAS)来净化FWAD。结果表明,高浓度的悬浮固体(SS)(16439±475mg/L),化学需氧量(COD)(24642±1301mg/L),氨氮(NH4-N)(2641±52mg/L)是影响常规活性污泥法净化FWAD效率的主要因素。通过实施固液分离的生物调理脱水,接近100%的SS和总磷(TP),90%的COD,总氮(TN)的38%,消化物中37%的NH4+-N可以有效去除或回收,因此产生具有相对较低污染负荷的透明滤液和干污泥饼(<60%的水分含量)。此外,氨汽提和生化处理后,废水符合中国规定的相关排放标准,随着COD的浓度,TN,NH4+-N,TP范围为151至405、10-56、0.9-31和0.4-0.8mg/L,分别。这种提出的BDAS方法表现出稳定的性能和低的运营成本,提供了一个有前途的解决方案,在实际工程中纯化FWAD,同时实现资源回收。
Although anaerobic digestion is the mainstream technology for treating food waste (FW), the high pollutant concentration in the resultant food waste anaerobic digestate (FWAD) often poses challenges for the subsequent biochemical treatment such as activated sludge process. In this study, taking a typical FW treatment plant as an example, we analyzed the reasons behind the difficulties in treating FWAD and tested a novel process called as bio-conditioning dewatering followed by activated sludge process (BDAS) to purify FWAD. Results showed that high concentrations of suspended solids (SS) (16439 ± 475 mg/L), chemical oxygen demand (COD) (24642 ± 1301 mg/L), and ammonium nitrogen (NH4+-N) (2641 ± 52 mg/L) were main factors affecting the purification efficiency of FWAD by the conventional activated sludge process. By implementing bio-conditioning dewatering for solid-liquid separation, near 100% of SS and total phosphorus (TP), 90% of COD, 38% of total nitrogen (TN), and 37% of NH4+-N in the digestate could be effectively removed or recovered, consequently generating the transparent filtrate with relatively low pollution load and dry sludge cake (<60% of moisture content). Furthermore, after ammonia stripping and biochemical treatment, the effluent met the relevant discharge standards regulated by China, with the concentrations of COD, TN, NH4+-N, and TP ranging from 151 to 405, 10-56, 0.9-31, and 0.4-0.8 mg/L, respectively. This proposed BDAS approach exhibited stable performance and low operating costs, offering a promising solution to purify FWAD in practical engineering and simultaneously realize resource recovery.