Research progress on the influence of solid carbon source characteristics on biological denitrification technology
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摘要:
固相碳源反硝化技术是处理低碳氮比污水的重要手段之一,其影响生物反硝化效率的重要因素是碳源特性。针对碳源的自身特性对反硝化的作用原理尚不明晰的问题,从固相碳源应用于脱氮的原理出发,比较和揭示了不同类型固相碳源(人工合成可生物降解聚合物、天然纤维素物质和混合固相碳源)的优势与应用前景,详细梳理了碳源的理化性质(合成物质、释碳组成、表面特性)和投加位点等对污水处理中生物反硝化过程的影响。结果表明,固相碳源的释碳量和利用率是影响反硝化效率的重要因素,通过优化材料组成和混合方式等来改变材料特性可以实现释碳最大化利用,使释放组分更好地被反硝化微生物利用。提出未来固相碳源领域应从改进碳源合成方式和研究电子传递机理等角度优化释碳能力及提高反硝化速率,以期深入开发及推广新型的固相碳源。
Abstract:Solide carbon source denitrification technology is a pivotal strategy for treating low carbon-to-nitrogen (C/N) wastewater, and the important factor affecting the efficiency of biological denitrification is the characteristics of the carbon source. The advantages and application prospects of various types of solid carbon sources, including synthetic biodegradable polymers, natural cellulosic substances, and mixed solid carbon sources, were compared and elucidated, aiming at the unclear principle of their application in nitrogen removal. Detailed analysis was conducted on the influences of physical and chemical properties of carbon sources (such as synthetic substances, carbon released composition, and surface characteristics) and the dosing sites, etc. on the biological denitrification process. The results indicated that the carbon release and its subsequent utilization rate by denitrifying microorganisms were crucial determinants of denitrification efficiency. By optimizing material composition and mixing methods to modify the material characteristics, carbon release could be maximized and the released components could be better utilized by denitrifying microorganisms. It was proposed that the future solid carbon source field should focus on enhancing carbon release capabilities and denitrification rates through advancements in the synthesis of carbon sources and the elucidation of electron transfer mechanisms, to deeply develop and promote novel solid carbon sources.
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Key words:
- denitrification /
- solid carbon source /
- characteristic /
- biodegradable polymer /
- nitrogen pollution
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表 1 不同类型固相碳源反硝化速率对比
Table 1. Comparison of denitrification rates of different types of solid carbon sources
碳源类别 碳源名称 规格/mm 反硝化速率/
〔mg/(L·h)〕水力停留
时间(HRT)/h天然纤维素物质 小麦秸秆[35] 10×20 1.6~2.2 木屑[36] 1.0~5.0 1.49~7.27 玉米芯[37] 20×20 8.46 1.77 人工合成
可生物降解聚合物PBS[38] 3 28.4 0.5 PBS[39] 5×3 22.08 8 PCL[40] 2.5~3.5 19 1.5 PCL[41] 2×3×4 30.3 5.5 PCL[42] 2~3 11.25 5 PHBV[43] 4.0~6.5 10.04 2.6 PHBV[44] 3×3 32.08 0.5 PHBV[45] 3.2×3.1 27.9 0.5 PLA[46] 3.02×
(2.22~3.60)1.65 PHB[5] 1.49 7~41 0.75~1.25 混合固相
碳源PHBV-
竹屑[47]3.5×2.5 5.0~7.5 2~3 PBS-竹屑[48] 10×10 28.33~34.58 PCL-淀粉[49] 3~5 2.88 PO-淀粉[50] 1×2×3 2.5~4.5 2.3~3.3 表 2 不同固相碳源反应体系中功能微生物分析
Table 2. Analysis of functional microorganisms in reaction systems of different solid carbon sources
碳源类别 碳源名称 水解微生物 反硝化微生物 特殊微生物 反应器 天然纤维素物质 小麦秸秆[54] 肠杆菌属、马赛菌属、芽孢杆菌属、鞘氨醇杆菌属 实验室锥形瓶 美人蕉、稻草、花生壳[55] 变形菌门、绿弯菌门、拟杆菌门、放线菌门 人工湿地 人工合成
可生物降解
聚合物PHBV(15 mg/L
硝态氮)[26,54]黄杆菌属、假单胞菌属、
螺旋体属固氮螺菌属、脱氯单胞菌、索氏菌属 脱硫弧菌(将硝酸盐或亚硝酸盐还原为氨) 实验室填充床 PHBV(100 mg/L
硝态氮)[44]黄杆菌属、单胞菌属、
氢噬菌属、巨球形菌属假单胞菌属、脱硫弧菌属、脱氯单胞菌、单胞菌属 管道杆菌属(产生细胞外的聚合物质,有利于微生物的生长和生物膜的形成),梭状芽孢杆菌(产氢) 实验室填充床 PHBV[47] 梭状芽孢杆菌属、
丛毛单胞菌科丝硫细菌属 PBS(盐度0‰)[39] 嗜酸菌属、固氮弧菌属、阿菲波菌属、从毛单胞菌属 热单胞菌属、根瘤菌属、单胞菌属、慢生根瘤菌 循环水养殖系统 PBS(盐度25‰)[39] 嗜酸菌属 白色拉布伦茨氏菌属、
副球菌属无氮菌(同时具有反硝化和降解功能的微生物) 循环水养殖系统 混合固相碳源 PBS-竹屑(盐度0‰)[56] 嗜酸菌属 SM1A02(厌氧氨氧化) 循环水养殖系统 PBS-竹屑(盐度25‰)[56] Formosa (一种具有反硝化和降解功能的微生物) 海胞菌属 SM1A02(厌氧氨氧化) 循环水养殖系统 PHBV-淀粉[47] 梭状芽孢杆菌属 脱氯单胞菌属、细小好氧反硝化菌属 填充床反应器 PHBV-竹屑[47]、
PHBV-PLA-木屑/
零价铁[57]梭状芽孢杆菌属、
未分类的小单胞菌属、未分类的噬几丁质菌科、SBR1031、A4b、柳叶弯曲杆菌属、慢生根瘤菌属丝硫细菌属、
固氮螺菌属、未经分类的红环菌科、脱硫弧菌属未经培养的螺旋杆菌科(自养硝酸盐还原)、
未分类的嘉利翁菌科、地发菌属、地杆菌科填充床反应器 玉米芯-硫铁复合填料[58] 变形菌门、拟杆菌门、螺旋菌门、密螺旋体属、螺旋体科 红环菌科、丛毛单胞菌科、索氏菌属、
贝日阿托菌属酸杆菌门 实验室填充床 -
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