Study On Preparation And Application Of T Series High-efficiency Decoloring Flocculant In Dyingstuff Wastewater Treatment

Since the dyeing industry has the characters of containing much organic waste, high chromaticity and the fast change of pH value, it has become one of the difficult treatment wastewater. In the dye wastewater treatment process, decolorization is the most difficult. There are many different types of depigmenting agents, decolorization effect is the best condensate, but the processing cost is high. In this paper, under certain conditions, on the based materials of dicyandiamide and formaldehyde, the dicyandiamide-formaldehyde decolorization flocculant was synthesized. Use it to deal with dye wastewater well, proved dicyandiamide-formaldehyde decolorization flocculant is a promising flocculant.By design orthogonal, the synthetic conditions of dicyandiamide-formaldehyde decolorization flocculant has been optimized. Use it to deal with anthraquinone,azo dye and other types of wastewater well. Flocculant and inorganic coagulants complex used to deal with dye wastewater, not only to obtain good result, but also deal with significant lower costs.Come through the test, the best synthesis condition of decoloration flocculant is: the temperature is 70～80℃, the time is 3.5 hour, a variety of materials ratio is n(dicyandiamide):n(formaldehyde):n(ammonium chloride):n(urea):n(sodium nitrite) is 1:2.4:0.7:0.1:0.05, modifier ammonium chloride as a additional batches. Product for basic performance is: solid content 52%, density 1.247g/cm3, viscosity 550mP.s, pH is 6, look for yellow, transparent, sticky, better liquidity liquid.Use dicyandiamide-formaldehyde decolorization flocculant studied the effects of four types of dye wastewater. The result show that: all kinds of dye wastewater can be decolorization rate reached 99%; CODCr removal rate was also up 60% to 90%. To deal with disperse waste water is the best, to deal with acid dyes,reactive dyes followed by results effluent, to deal with bromide acid aqueous solution as opposed to the worst effects of the former.Use the method of orthogonal design studied the formulation of the decolorization flocculant and synthetic conditions. It was found that: In the synthesis process, adding a certain proportion of inorganic coagulant(the mass fraction of 10%), Control the temperature is 40～50℃, the time is 2 hour, preparation of T composite decolorization flocculant deal with reactive waste water well. Inorganic coagulant were ferrous sulfate(T1),ferric chloride(T2),PAC(T3),aluminum sulfate (T4) deal with reactive red X-3B and reactive red K-2BP dye wastewater, decolorization rate of above 99%, CODCr removal rate of close to 80%.Use T series decoloring flocculant to deal with the Ullman condensation actual production waste water (color absorption 25.74,CODCr 11954mg/L) well. When adding quality 650mg/L, decolorization rate about 90%, CODCr removal about 65%; when the actual waste water pH<8, to deal with the conditions better than others.