【作者】 陈川；

【导师】 李笃中； 任南琪；

【作者基本信息】 哈尔滨工业大学 ， 环境科学与工程， 2011， 博士

【摘要】 针对高含硫含氮有机废水的水质复杂和现有生物处理技术工艺系统复杂,运行操作成本高,氮硫去除能力低下等技术瓶颈,提出了自养菌-异养菌协同反硝化脱硫技术,该技术基于自养微生物和异养微生物的协同作用,可实现硫化物、硝酸盐和有机碳的同步高效去除,同时将硫化物转化为单质硫实现资源化回收,消除二次环境污染,是一种高效、经济、稳定、先进的生物处理工艺。本研究主要围绕自养菌-异养菌协同反硝化脱硫工艺（A&H-DSR）的运行与调控策略展开研究,考察了反硝化脱硫工艺的运行效能和影响因素,提出了微氧强化技术来解决高浓度硫化物的抑制,分离筛选到高效脱硫异养菌株Pseudomonas sp. C27,打破了自养微生物反硝化脱硫的传统观念,对自养微生物和异养微生物协同规律的探索提供了崭新的思路;并分析了工艺系统内自养微生物和异养微生物对反硝化脱硫工艺的贡献,从而为提高工艺运行效能和解决高浓度有毒硫化物的抑制所采取的调控策略提供了重要的理论基础。通过不同反应器的运行确定了膨胀颗粒污泥床反应器（EGSB）为反硝化脱硫工艺的最佳形式,同时考察了碳氮比、硫化物浓度、负荷等对反硝化脱硫工艺的运行效能的影响,确定最佳的摩尔硫氮比和碳氮比为5:6和1.26:1;此外,反硝化脱硫工艺可实现的最大处理负荷为6.09 kgS/m³.d^-1,3.11 kgN/m³.d^-1,8.04kgAc-/m³.d^-1。针对高浓度硫化物抑制反硝化脱硫工艺的运行效能,提出微氧强化技术;在微氧条件下,反硝化脱硫工艺耐受硫化物的上限由200mg/L提高到300mg/L;此外,通过对功能菌团功能酶的活性分析,发现微氧环境可以刺激硫化物氧化酶的分泌进而提高反硝化脱硫效能。从DSR-EGSB反应器的颗粒污泥中分离获得高效脱硫的异养菌株Pseudomonas sp. C27,该菌株在异养反硝化条件下可以同时高效氧化硫化物,是自养微生物降解硫化物速率的2倍以上;基于电子平衡和物料平衡分析,还提出了C27可能的代谢途径。此外,微氧条件同样可以强化菌株C27的反硝化脱硫能力,将菌株C27忍受硫化物浓度的上限提高到300mg/L。菌株C27在连续流运行下,进水硫化物浓度被提高到561.4mg/L,负荷为0.215 kgS/m³.d^-1、0.146 kgN/m³.d^-1、0.092 kgC/m³d^-1,硫化物和乙酸盐的去除率为84.7%和74.1%,硝酸盐去除率在99%以上,连续流运行相对间歇式试验有效缓解了高硫化物浓度的抑制。通过采用EGSB反应器考察自养、异养和混合营养条件下反硝化脱硫的运行效能发现,在自养条件下运行反应器,工艺所能忍受的最大负荷为1.6 kgS/m³.d^-1,当继续增加负荷,将会导致系统的崩溃,而将自养条件运行转到混养条件运行,系统的处理效能得到成功恢复;说明异养功能微生物在反硝化脱硫工艺系统中起到了关键的作用。此外,反硝化脱硫工艺系统在高负荷下崩溃的原因,主要是由于异养反硝化微生物受到了逐渐累积的高浓度硫化物的抑制,从而出现了亚硝酸盐的大量累积,而亚硝酸盐的累积又会导致乙酸盐的去除能力下降,进而导致了系统的崩溃;为了能够恢复崩溃的系统,可以采用微氧调控来缓解硫化物的抑制进而强化反硝化脱硫工艺使其具有更高的处理效能。更多还原

【Abstract】 Based on the current complicated, high-cost and low efficiency bio-technology for high strength sulfur and nitrogen containing wasterwater treatment, the autotrophic and heterotrophic denitrifying sulfide removal process （A&H-DSR） was developed. The sulfide, nitrate and organic carbons are simultaneously converted to sulfur, N2 and CO2 by DSR process in which the symbiosis of autotrophs and heterotrophs exists. So, the DSR process is a high effective, low cost , high stable and advanced biotechnology for wasterwater treatment.This study mainly focuses on the operation and control strategy of DSR process. The performance and key parameters were determined in this study, and the high-effective sulfide-degrading strains Pseudomonas sp. C27 was isolated , indicating that the traditional metabolic pathway of sulfide removal by autotrophic bacterias are reversed. The high-effective abnormal behavior of sulfide removal for C27 provided a new way to study the cooperation of autotrophs and heterotrophs. On the other hand, the contribution of autotrophic and heterotrophic denitrification to the performance of DSR process was analyzed aiming to select reasnonable control strategies to enhance the performance and mitigate the inhibition by high levels of sulfide.The expanded granular sludge bed reactor was choosed as optimal operational mode for DSR process. The optimal molar ratios of S/N and C/N was determined as 5:6 and 1.26:1. Furthermore, the maximum sustainable loading rates of DSR process was 6.09 kgS/m³.d^-1,3.11 kgN/m³.d^-1,8.04kgAc-/m³.d^-1。The technology of micro-aerobic enhancement successfully mitigated the sulfide inhibition to the performance of DSR process. The maximum sustainable sulfide concentration was increased from 200mg/L to 300mg/L; Also, based on the analysis for the activity of functional enzymes, the sulfide oxidase was stimulated to secrete by functional strains, hence enhancing the performance of DSR process.The high-effective sulfide-degrading strains C27 can oxidize sulfide under the denitrifying condition, and the sulfide-oxidizing rate was two times more than that of autotrophic sulfide-oxidizers. The suggested metabolic pathway for C27 was provided based on the electrion balance and mass balance. Futhermore, the micro-aerobic conditions also can enhance its performance of denitrifying sulfide removal and its sustainable sulfide level of 300mg/L.In continuous flow test for C27, at the sulfide concentration of 561.4mg/L corresponding to the loadings of 0.215 kgS/m³.d^-1、0.146 kgN/m³.d^-1、0.092 kgC/m³d^-1, the removal of sufide, acetate and nitrate was 84.7%, 74.1% and >99% .The performance of DSR process was estimated under autotrophic, heterotrophic and mixotrophic conditions, and the results showed that the maximum sustainable loadings for autotrophic conditions was 1.6 kgS/m³.d^-1, or the system will breakdown. The performance under the operations of mixotrophic meidum were much better than that under autotrophic conditions, and the operations of mixotrophic condition can restore the system breakdown under the running of autotrophic medium. Additionally, the reseaons for the systematic breakdown of DSR process were that the heterotrophic denitrifiers were inhibited by high levels of sulfide leading to the numerous nitrite accumulation and the worse capacity of acetate removal. To restore the systematic breakdown and enhance the performance, the technology of micro-aerobic enhancement can be used.更多还原