【作者】 赵旭；

【导师】 韩海荣； 王毅力；

【作者基本信息】 北京林业大学 ， 生态学， 2004， 硕士

【摘要】 本文针对给水水源中备受关注的腐殖酸为对象，采用烧杯实验法比较了混凝—气浮工艺与混凝—沉淀工艺的处理性能，并通过UV_254nm，总有机碳（TOC），高锰酸钾指数(COD_Mn)，浊度等指标的测定结果，以无机低分子絮凝剂（硫酸铝，氯化铁）作为参考，着重研究了无机高分子絮凝剂（PAC，PFC）在强化混凝—气浮工艺中的投药量、原水pH值、离子强度、快速混合搅拌强度和时间、絮凝搅拌强度和时间、回流比以及共聚方式的效果等方面的内容，确定了上述条件的最佳范围，即强化混凝—气浮工艺相应的工艺条件。 结果表明，混凝—气浮工艺对腐殖酸去除率稳定的投药量范围比混凝—沉淀工艺窄，但前者对未过滤水样中腐殖酸的去除效果比后者好，对溶解性腐殖酸的去除，较低投药量时前者比后者好，较高投药量时趋势正好相反。强化混凝—沉淀工艺处理腐殖酸的最佳pH范围是4.5—8.2，强化混凝—气浮工艺比混凝—沉淀工艺大约推后了0.5—1.2pH单位。 对于强化混凝—气浮工艺而言，最佳混凝化学条件和水力学条件为：（1） 最佳投药量范围：PAC是1.7—2.4mmol／L(以Al³⁺计)；PFC是0.19-0.56mmol／L、0.75mmol／L(以Fe³⁺计)。（2） 最佳pH范围：PAC是6—8.1；PFC是5—6.5、8—10。（3） PAC和PFC的最佳离子强度小于0.001mol／L。（4） 最佳水力学条件：快速混合的搅拌强度250—750s^-1、快速混合的搅拌时间15—120s、絮凝搅拌强度20—200s^-1、絮凝搅拌时间3—10min（PAC）；快速混合搅拌强度250—500s^-1、快速混合搅拌时间15—120s、絮凝搅拌强度20—100s^-1、絮凝搅拌时间3—8min（PFC）。（5） PAC的最佳回流比范围10％—15％，PFC的最佳回流比是10％。（6） 共聚溶气气浮工艺比传统的溶气气浮工艺对有机物或无机物的去除有一定的提高，但并不明显。更多还原

【Abstract】 The removal efficiency of humic acid in water by coagulation-sedimentation process (CS) and coagulation-dissolved air flotation (CDAF) process was assessed by the static jar test. A series of contrast experiments were carried out to study the chemical and hydraulic effect factors of inorganic polymer flocculant(PAC , PFC) on removing humic acid(HA) in water by enhanced coagulation-dissolved air flotation process with measuring the following water quality index of UV,TOC,CODMn and turbidity. The optimum chemical and hydraulic effect factors scopes were determined.The results showed that the broader dosage scope of stable removal ratio was found in coagulation-sedimentation (CS) process than coagulation-DAF (CDAF) which removed more HA (in un-filtrated water). As to removal of dissolved HA,CDAF process had a better performance than CS one at some low doses,but at doses more than these the trend was opposite.Furthermore,CDAF process retarded 0.5-1.2 pH unit from the initial point of the optimum pH scope 4.5-8.2 in CS.The optimum operational conditions of CDAF were:(1)The optimum dose scopes of PAC are 1.7-2.4mmol/L and that of PFC are 0.19-0.56mmol/L, 0.75mmol/L.(2)The optimum pH scopes of PAC are 6 - 8.1 and that of PFC are 8 -10, 5- 6.5.(3)The optimum ion intensity of PAC and PFC is less than 0.001mol/L.(3)The optimum hydraulic conditions :the optimum coagulation Mixing intensity scopes are 250-750s-1 (as PAC), 250-500s-1 (as PFC),the optimum coagulation Mixing time scopes arel5 - 120s(as PAC and PFC),the optimum flocculation Mixing intensity scopes are 20-200s-1 (as PAC) 20- 100s-1(as PFC),the optimum flocculation Mixing time scopes are 3 - 10min(as PAC), 3- 8min (as PFC) .(5)The optimum recycle ratio scopes of PAC are 10% -15%, The optimum recycle ratio scope of PFC is 10%.(6)The removal efficiency of humic acid was increased indistinctively by co-flocculation.更多还原