煤化工废水成分复杂,以许多剧毒的芳香族化合物为标志,导致生化处理系统的不稳定,导致治疗效果欠佳。在这项研究中,建立了生化处理系统,通过定量调节共代谢底物的剂量来有效降解芳香族化合物(具体而言,化学需氧量(COD)葡萄糖:COD乙酸钠=3:1、1:3和1:1)。结果表明,在COD葡萄糖与COD醋酸钠的比例为3:1的条件下,该系统达到最佳性能。当共代谢底物以最佳比例添加到系统中时,污染物去除和累积效果的检测表明,COD和总有机碳(TOC)的去除效率分别达到94.61%和86.40%,分别。苯系物的去除率,氮杂环化合物,多环芳烃,酚类是100%,100%,63.58%,94.12%,分别。对微生物细胞生理反应的研究表明,在最优比例调节下,共代谢底物导致微生物胞外聚合物(EPS)分泌大幅增加,特别是细胞外蛋白质。当系统运行结束时,最佳组蛋白质的松散结合EPS(LB-EPS)和紧密结合EPS(TB-EPS)含量分别为7.12mg/g-SS和152.28mg/g-SS,分别。同时,在最佳组中,α-螺旋/(β-片随机线圈)的比率和分子间相互作用力的比例也增加。在系统完成时,α-螺旋/(β-片+随机线圈)的比值达到0.717(LB-EPS)和0.618(TB-EPS),分别。此外,分子间相互作用力的比例分别达到74.83%(LB-EPS)和55.03%(TB-EPS)。对微生物代谢调节的深入分析表明,引入最佳比例的共代谢底物有助于儿茶酚2,3-双加氧酶(C23O)和脱氢酶(DHA)表达的显着上调。测定C23O和DHA的表达水平为0.029U/mgPro·gMLSS和75.25mgTF·(gMLSS·h)-1(峰值),分别。相应地,富集芳香化合物降解菌,包括Thauera,糖果酱,和候选人_竞争对手,发生,随着相关功能基因如儿茶酚1,2-双加氧酶的上调,儿茶酚2,3-双加氧酶,原儿茶酸3,4-双加氧酶,和原儿茶酸4,5-双加氧酶。考虑到实际CCW中多种共存芳族化合物的复杂系统,这项研究不仅获得了最佳的碳源添加比例,而且提高了碳源的有效利用,提高了系统有效降解芳香族化合物的能力。此外,本文为复杂系统的生化处理中的代谢调控和无害化处理奠定了理论基础,以真实的CCW为例。
The complex composition of coal chemical wastewater (CCW), marked by numerous highly toxic aromatic compounds, induces the destabilization of the biochemical treatment system, leading to suboptimal treatment efficacy. In this study, a biochemical treatment system was established to efficiently degrade aromatic compounds by quantitatively regulating the dosage of co-metabolized substrates (specifically, the chemical oxygen demand (COD) Glucose: COD Sodium acetate = 3:1, 1:3, and 1:1). The findings demonstrated that the system achieved optimal performance under the condition that the ratio of COD Glucose to COD Sodium acetate was 3:1. When the co-metabolized substrate was added to the system at an optimal ratio, examination of pollutant removal and cumulative effects revealed that the removal efficiencies for COD and total organic carbon (TOC) reached 94.61 % and 86.40 %, respectively. The removal rates of benzene series, nitrogen heterocyclic compounds, polycyclic aromatic hydrocarbons, and phenols were 100 %, 100 %, 63.58 %, and 94.12 %, respectively. Research on the physiological response of microbial cells showed that, under optimal ratio regulation, co-metabolic substrates led to a substantial rise in microbial extracellular polymeric substances (EPS) secretion, particularly extracellular proteins. When the system reached the end of its operation, the contents of loosely bound EPS (LB-EPS) and tightly bound EPS (TB-EPS) for proteins in the optimal group were 7.12 mg/g-SS and 152.28 mg/g-SS, respectively. Meanwhile, the ratio of α-Helix / (β-Sheet + Random coil) and the proportion of intermolecular interaction forces were also increased in the optimal group. At system completion, the ratio of α-Helix / (β-Sheet + Random coil) reached 0.717 (LB-EPS) and 0.618 (TB-EPS), respectively. Additionally, the proportion of intermolecular interaction forces reached 74.83 % (LB-EPS) and 55.03 % (TB-EPS). An in-depth analysis of the metabolic regulation of microorganisms indicated that the introduction of optimal ratios of co-metabolic substrates contributed to a noteworthy upregulation in the expression of Catechol 2,3-dioxygenase (C23O) and Dehydrogenase (DHA). The expression levels of C23O and DHA were measured at 0.029 U/mg Pro·g MLSS and 75.25 mg TF·(g MLSS·h)-1 (peak value), respectively. Correspondingly, enrichment of aromatic compound-degrading bacteria, including Thauera, Saccharimonadales, and Candidatus_Competibacter, occurred, along with the upregulation of associated functional genes such as Catechol 1,2-dioxygenase, Catechol 2,3-dioxygenase, Protocatechuate 3,4-dioxygenase, and Protocatechuate 4,5-dioxygenase. Considering the intricate system of multiple coexisting aromatic compounds in real CCW, this study not only obtained an optimal ratio for carbon source addition but also enhanced the efficient utilization of carbon sources and improved the capability of the system to effectively degrade aromatic compounds. Additionally, this paper established a theoretical foundation for metabolic regulation and harmless treatment within the biochemical treatment of intricate systems, exemplified by real CCW.