【作者】 胡剑；

【导师】 颜幼平；

【作者基本信息】 广东工业大学 ， 环境工程， 2012， 硕士

【摘要】 进入新世纪以来,我国的皮革产业得到迅猛发展,在世界上确立了皮革生产和贸易大国的地位,同时也带来了严峻的环保问题,成为皮革行业可持续发展的最大外界制约因素。事实上,制革工业只能将20%左右的原料皮转化为皮革,其余部分则成为副产品或污染物,而且在皮革的加工过程中还需加入多种化工药剂,却只有一部分被吸收利用,其余均汇入废水当中,导致制革废水的成分十分复杂,往往含有高浓度的有机物、氨氮,以及具有生物毒性的铬离子和硫离子,普通生化处理往往存在操作难度大、处理成本过高和难以稳定达标的问题,这些问题使得制革废水成为目前工业废水处理的难点之一。电化学法具有处理能力稳定高效和无二次污染等特点,在废水处理方面拥有巨大的发展潜力。随着近些年来对电催化氧化电极的深入研究,开发出了大量不同材质的电极材料,使电极各方面的性能得到了大幅提高,对废水的处理能力也得到了大幅加强,越来越接近甚至已经投入到废水处理的工业化运用当中。本文采用先进的金属铌覆盖掺硼金钢石(Nb/BDD)膜电极对制革综合废水进行电化学处理研究。在研究的准备阶段,测试了电极的性能,并对制革综合废水进行了预处理,然后通过单因子控制实验,考察了各项因素对处理效果的影响,同时分析其机理,最后通过正交实验,确定最佳的实验条件。实验结果表明：(1)碱一混凝沉淀法对制革综合废水中的Cr3+和SS具有非常好的去除效果。(2)金属铌覆盖掺硼金钢石膜电极(Nb/BDD)拥有优良的稳定性和电化学性能。Nb/BDD电极表面结构密实,比表面积大,稳定性好,电势窗口宽达4.1V左右,析氧电位高达2.1V,析氢电位低至-1.9V,背景电流低至-8×10-6-6×10-7A。(3)时间、电流密度、电解质的种类和浓度、pH值的变化都会对电化学氧化速率、ECR和ACE产生较大的影响。最后,综合考虑各项影响因素,根据正交实验结果发现,在电流密度为40mA/cm2,电解质(NaCl)浓度为3.0g/L,pH值为2.0,电催化氧化处理2h后,废水的COD去除率达到了87.1%,比能耗为47.65kW-h/kgCOD,电流效率为34.63%。总的来说Nb/BDD电化学氧化技术对经过预处理的制革综合废水有着良好的处理效果,但能耗相对较高,尚需进一步改进。更多还原

【Abstract】 Get into a new century, the leather industry of our country gets a fast fierce development, is establishing leather production and trading the position of big country in the world, also brought a rigorous environmental protection problem at the same time, becoming the leather profession could keep on the biggest outside check and supervision factor of development。In fact, the rate of make raw material skin convert into leather is about20%in the leather industry, the rest part then becomes by-product or pollutant, and still needs and joins various chemical engineering medicines during the processing of leather, but only a part of absorbabilities make use of, the rest all remits among the waste water, cause the composition of making the tannery wastewater is very complicated, which usually imply a high density of organic matter, ammonia nitrogen, and chrome ion and sulphur ion that have a living creature toxicity, the common bio-chemical handles usually has several problem like:has greatly difficulty to operate, handle cost reach an unacceptable level and hard to attain the exhaust standard stably, which make tannery wastewater become one of the crux over the industrial waste water handles currently.The eletrocatalytic oxidation method own a huge development potential in the liquid waste processing for which has characteristics like efficient processing ability and with no two times pollute, etc. The each function of electrode got a significant exaltation along with the deep research of the electrode, this thesis describe an advanced Nb/BDD film electrode, and was used to Study on electrochemical treatment by handle the tannery effluent. At research of preparation stage, tested the function of electrode and pretreat the tannery effluent, then investigated each factor to processing the influence of effect since single factor experiment, analyze its mechanism at the same time, finally, make sure the best experiment condition since an orthogonal experiment.Experimental results show that:(1) Alkali-coagulant method is very effect to clean the Cr3+and SS of the tannery effluent.(2) The Nb/BDD electrode owns good stability and electrochemical performance. The Ti/BDD electrode surface structure is actually airtight, has a nice specific surface area and stability, Potential window is4.1V, The oxygen evolution potential is2.1V, Hydrogen potential is-1.9V, the background electric current is low to-8×10-6～6×10-7A.(3) Time、current density、the type and concentration of electrolyte、pH will influenced electrochemical oxidation rate、ECR and ACE to a large extent.At the end, comprehensive to consider each impact factor, according to the date of the orthogonal experiment, the best condition find is:current density is40mA/cm, the concentration of electrolyte (NaCl) is3.0g/L, pH is2.0, electrochemical oxidation react2hours later, the COD move rate of tannery effluent is87.1%, ECR is47.65kW-h/kgCOD, ACE is34.63%.In general, Nb/BDD electrochemical oxidation technology for pretreated tannery wastewater with good processing effect, But which is still need to be further improved for the relatively high energy consumption。更多还原