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排水管道是排水系统的重要组成部分,具有收集和输送污废水和雨水的功能,在保障居民生活卫生、控制水环境污染、降低洪涝灾害等方面发挥了重要作用[1]。在自身结构特征和外界环境因素的影响下,排水管道在长期运行过程中容易发生堵塞[2-3],堵塞造成的管道溢流风险将对周边居民正常生活和环境质量造成严重威胁[4-5],且疏通堵塞的运维费用消耗巨大[6]。为解决排水管道堵塞问题,行业内已开展大量研究,对排水管道的堵塞成因、发展机制和控制方法进行了广泛探索[7]。
脂肪、油和油脂 (fat, oil and grease,FOG) 沉积物的形成和发展是造成排水管道堵塞的关键因素之一[8],由FOG沉积物造成的排水管道堵塞占所有排水管道堵塞的40%~50%[9-10]。为解决排水管道堵塞问题,亟需开展针对排水管道内FOG沉积物的研究,解析其理化特征、形成机制和控制方法。目前,已有研究解析了FOG沉积物的物质组成、发展过程、控制方法等[11],然而研究对象和研究目标相对分散,亟待梳理关键参数并提出下一步的治理建议。
基于此,本研究系统调研现有排水管道FOG沉积物研究,总结排水管道内FOG沉积物的理化特征及形成机制,探讨排水管道FOG沉积物的控制方法并提出研究建议,以期为排水管道堵塞领域的进一步研究提供参考,并助推相关技术的研发和应用。
排水管道中脂肪、油和油脂 (FOG) 沉积物的理化特征、形成机制及控制方法
Physicochemical characteristics, formation mechanism and control methods of fat, oil and grease (FOG) deposits in drainage pipes
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摘要: 脂肪、油和油脂 (FOG) 沉积物是排水管道堵塞的重要成因,对其开展机制研究并开发控制技术对于提高排水管道运行安全性和稳定性具有重要意义。在统筹分析既有FOG研究的基础上,系统论述FOG沉积物的物理化学特征及其在排水管道内的形成机制,并对FOG沉积物的影响因素和控制方法进行深入探讨,重点解析排水管道进水FOG控制、FOG沉积物原位控制以及FOG资源化利用的研究成果,从而提出针对排水管道FOG沉积物的研究建议,为排水管道FOG沉积物控制提供参考。Abstract: Fat, oil and grease (FOG) deposits are important causes of drainage pipe clogging, it is of great significance to study the mechanism and develop the control technology for improving the safety and stability of drainage pipe operation. Based on the comprehensive analysis of existing FOG research, the physicochemical characteristics of FOG deposits and their formation mechanism in drainage pipes were systematically discussed, and the influencing factors and control methods of FOG deposits were thoroughly explored. The research results of drainage pipe inlet FOG control, in-situ FOG deposit control and FOG resource utilization, were analyzed, so as to propose research recommendations for drainage pipe FOG deposits and provide reference for drainage pipe FOG deposit control.
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Key words:
- fat, oil and grease(FOG) deposits /
- drainage pipes /
- formation mechanism /
- blockage /
- treatment
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表 1 隔油池改进措施的对比
Table 1. Comparison of improvement measures of grease trap
改造方式 改造措施 去除效果 参考文献 优化进水特征 进水温度从21 ℃增加到38 ℃ FOG去除率下降10% [40] HRT从20 min增加到1 h时 FOG最大去除率90% [37] 乳化强度降低 FOG最大去除率为82% [40] 进水流速增加 FOG去除效率提高 [40] 改造内部结构 缩短入口管道且取消中间挡板 FOG最大去除率85% [37] 使用扩口管道 FOG最大去除率83% 分流式入口管道和挡板管道 FOG最大去除率87% 安装斜管沉淀器 HRT≤30 min,FOG去除率提高10% [41] HRT≥30 min,FOG最大去除率87% 增加筛网、一级和二级沉淀池、FOG分离室和毛发过滤器隔间 FOG最大去除率93% [42] 表 2 不同生物降解剂对FOG去除效率的对比
Table 2. Comparison of FOG removal efficiency of different biodegraders
生物降解剂 菌种名称 菌株个数 适应水体 处理效率 参考文献 IHI-91 嗜热芽孢杆菌 1 温度范围较宽的水体 三烯酸 (存在于橄榄油中)
去除率93%[49] D2D3 铜绿假单胞菌 1 环境变化较大的水体 FOG最高去除率97%~99% [50] 芽孢杆菌和假单胞菌
CP1的混合体芽孢杆菌 1 橄榄油和黄油含量较多的水体 橄榄油去除率94%
黄油的去除率97%[52] 假单胞菌 1 多菌种:F69 枯草杆菌 13 脂肪含量复杂的水体 FOG降解率提高37%~67% [54] 巨大芽孢杆菌 4 苏云金芽孢杆菌 6 嗜热脂肪杆菌 3 地衣芽孢杆菌 5 多粘芽孢杆菌 4 枯草芽孢杆菌 2 芽孢乳酸杆菌 2 芽孢杆菌 5 酵母菌 2 荧光假单胞菌 5 施氏假单胞菌 3 潮湿纤维单胞菌 1 微球菌 1 新型硫杆菌 1 -
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