| With the increasing volume of sewage discharge and increased depth of treatment sludge disposal problem has become increasingly prominent. Cationic polyacrylamide(CPAM) as a class of preferred flocculation, currently in China has been widely used in sludge conditioning. Conventional polymerization method generally by increasing the molecular weight of CPAM to improve their conditioning properties, and less concerned about the impact sequence structure CPAM conditioning properties of the sludge. Paper polymerized to form high molecular weight and having a micro block structure cationic polyacrylamide flocculant P(AM-DMC) by template polymerization and UV irradiation way, to apply to study sludge conditioning properties.In this paper, the experiment is under ultraviolet light trigger, an anionic polymer sodium polyacrylate(PAAS) as template,using methacryloyloxyethyl trimethyl ammonium chloride(DMC) monomer as a cationic monomer, together with acrylamide(AM) monomers for preparing cationic polyacrylamide P( AM / DMC), the main contents and conclusions are as follows:① Through single factor analysis and orthogonal analysis method,with relative molecular mass as an index to study the influence of various factors on the polymerization reaction and to determine the optimum conditions: the molar mass ratio of template and cationic monomer n(PAAS): n(DMC)(i.e., T: D ratio) = 0.5, The total monomer mass fraction 25%, DMC mass fraction of 20%, an initiator V-044 concentration of 0.07%, the reaction system p H = 4, the urea concentration of 0.3%, under UV irradiation time 60 min, the optimum conditions for the preparation of templates available polymer P(AM-DMC) relative molecular weight of up to 6.17 million. By variance analysis and intuitive analysis of orthogonal experiment shows that the impact of various factors on the template polymer P(AM-DMC) molecular weight of the order: V-044 initiator concentration> DMC content> p H value> UV irradiation time> urea concentration;② By infrared spectroscopy(FT-IR) and proton nuclear magnetic resonance spectroscopy(1HNMR) based on the synthesis of cationic polyacrylamide dilute acid amide P(AM-DMC) product is a copolymer of monomer AM and DMC and micro-block structure; by DTA- TG analysis(DTA-TGA) can be seen, the product has good thermal stability in the temperature range of 30 ℃ ~ 200 ℃ less prone to decomposition;③ Through the sludge dewatering applications, determinate the moisture content of the cake, filtrate turbidity and Zeta potential and other performance indicators, the following results can be obtained: Template Polymer P(AM-DMC) optimal dosage is about 40 mg / L, the choice synthetic products under optimum conditions and at 40 mg / L dosage, dewatered sludge cake moisture content up to 72.1%, more than the filtrate turbidity is 5.13 NTU, Zeta potential 0.307mv; p H of the sludge system is 6-7, the sludge dewatering best.④ By comparing the sludge dewatering effect between template polymerization products and no template polymerization products, homemade P(AM-DMC) and commercial CPAM,it can be drawn: template polymerization products of various sludge dewatering performance indicators are better than no template polymerization products, this is because the produce micro block structure and capacity in improved electrical flocculant; homemade template polymer P(AM-DMC) due to both its bridging capability and charge neutralization capacity are good, its sludge dehydration better than Japanese CPAM goods and Shandong CPAM products. |
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