Study On Treatment Of Tannery Effluent By Eletrocatalytic Oxidation Method

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。...