| The issue of water resource shortage and water environmental pollution of our country has been the important factors of restricting national economic and social development of our country. Studying developing and applying higher effect, lower cost, safe and non-secondary pollution water treatment chemical has been the important subject wastewater treatment field expects urgently to be solved. Flocculant is the most important and frequently used water treatment chemical. Constantly studying and developing new-style, higher effect water treatment flocculant, which can meet the demand of industry and sanitary sewage disposal, is the focus the water treatment and environmental protection circle have been caring about all the time.In this paper a new composite flocculant (attained based on CF-PAC, Al-pillared rectorite and chitosan)applied to treat with petrochemical wastewater and papermaking wastewater treatment has tested and investigated carefully and deeply. Inorganic flocculant CF-PAC, Al-pillared rectorite act as sorption mostly ; Meanwhile organic flocculant chitosan acts as the adsorption bridge mainly. Chitosan coagulates fine flocci together into lager, impact floccules and greatly strengthens the polymerization degree and coacervation force. The sedimentation rate and adsorption efficiency rise greatly. So the flocculation efficiency of this composite flocculant is superior to the single one. The course of studying can be divided into two parts.The first part is about the preparation of Al-pillared rectorite. The effect of preparation method of Al-pillared agent, rectorite suspending concentration, Al-pillared agent dosage, pillaring reacting temperature, pillaring reacting time are investigated; The optimum process condition is determined. The capability has compared with the nature rectorite. It is characterized by X-ray Diffraction and infrared spectrum. The result shows: Al-pillared agent isn't change the molecular structure of rectorite, just exchange the cations of layers, which enlarges the two-dimensional channels of rectorite, Whose level distance increases from 2.55nmto 2.66nm.Ratio surface area> the ionic exchange capacity and the pore aperture are increased. Compared with the nature rectorite, the efficiency of eliminating CODa and SS of Al-pillared rectorite are 38.95%and 12.91% higher than those by natural rectorite respectively, and the cost is reduced to some extent too.The second part focuses on the treatment research of the petrochemical wastewater and the papermaking wastewater using Al-pillared rectorite/chitosan composite flocculant. The optimal dosages and adding order for the petrochemical wastewater and the papermaking wastewater treatment using this composite flocculant are determined. The effect of pH value > reacting temperature > stirring speed and time^ resting time are studied. The optimal dosages and flow are obtained too. The result shows that this composite flocculant appears excellent flocculation efficiency. Compared with the composite flocculant of WuHan petrochemical factory, its capability is superior to it: the efficiency of eliminating CODo and SS are 28.75%and 8.29% respectively higher than those by flocculant of WuHan petrochemical factory, but the cost is46.63% lower; which is also far lower than the current average cost of petrochemical industry wastewater treatment. When dealing with papermaking wastewater, it can fully meet the require that WuHan ChenMing paper industry group put forward: The efficiency of eliminating CODcr higher than 25% based on the chemical cost controlled in 0.5 Yuan/ton sewage so as to better the gas float section. Those studies preparatorily show that this composite flocculant has particular effect and obvious economic n environmental benefit in industrial effluent treatment.
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