改性双氰胺-甲醛树脂对再生水的脱色效果

为了降低再生水的色度,通过正交试验的方法,以双氰胺-甲醛树脂为主体,分别以硫酸1+1(由1份浓硫酸与1份纯水制成)和氯化铵为改性剂制备改性双氰胺-甲醛脱色剂,并筛选最优脱色剂。结果表明,经氯化铵改性的双氰胺-甲醛脱色剂对再生水的脱色效果更好,且在双氰胺∶甲醛∶氯化铵∶水为1∶2. 3∶1∶4. 4(物质的量之比)、温度为70℃、反应时间为3 h条件下制备的脱色剂的脱色效果最好。采用该脱色剂进行中试,脱色效果良好,在进水染料浓度为20mg/L的条件下,沉淀池出水浓度在8 mg/L以下,脱色率超过60%。

Decolorization Effect of Reclaimed Water by Modified Dicyandiamide-formaldehyde Resin

Two groups of modified dicyandiamide-formaldehyde decolorizers were prepared in order to reduce the chromaticity of reclaimed water, through orthogonal test with dicyandiamide-formaldehyde resin as the main body and sulfuric acid 1+1( consisting of 1 part concentrated sulfuric acid and 1 part pure water) and ammonium chloride as the modifier. Meanwhile, optimal decolorizer was selected. The results indicated that the decolorization effect of dicyandiamide-formaldehyde decolorizer modified by ammonium chloride was better, and the best decolorization effect was achieved when the mole ratio of dicyandiamide : formaldehyde : ammonium chloride : water was 1:2. 3:1 -4.4, reaction temperature was 70 ℃ and reaction time was 3 hours. The decolorizer was used in a pilot test and good decolorization effect was realized. Under the condition of influent dye concentration of 20 mg/L, the effluent concentration was below 8 mg/L, and the decolorization rate was over 60%.