Nickel plating rinse water sewage wastewater treatment process and its economic benefit analysis
1, the membrane used for the hollow fiber membrane module ( 1 m2) , expressed in PS8. Operating pressure is 120 kpa, feed flow rate of 300 ml/min, the operating temperature is 25 ℃. Reaction tank in electroplating wastewater Ⅰ adding NaOH, generally speaking, when the solution C ( Ni2+) 0 x 10 5 mol/L, i. e. , Ni ( 哦) 15. Thus, for Ni ( 哦) 15, after treated with NaOH, Ni2 + and OH - rapid response generated Ni ( 哦) 0 mg/L. Ni( 哦) 2 colloidal precipitation similar to biological macromolecules, difficult to settlement separation. Through the hollow fiber membrane module filter, adjust the feeding speed of the pump to the set value, started to pump, then adjust the backflow ( Intercept liquid) On the pipeline valve, makes the ultrafiltration membrane module import and export pressure said the number of average of a set value ( The required operating pressure) , after the system is stable, in a certain period of time to collect the corresponding through fluid, used to detect. Ni( 哦) 2 concentrate is return of circulation, to concentrate Ni2 + 25 g/L, or import the reaction tank Ⅱ, join HCl, generate NiCl2 solution back to production process. Penetrant rho ( Ni2+) 0 mg/L, adjust pH value of solution in the regulating tank 7 or so, outside.
with atomic absorption spectrometer to determine GBC908/909 type nickel ion concentration. 1
treatment effect in electroplating wastewater adding NaOH, Ni2 + and OH - reaction Ni ( 哦) 2 precipitation. 0 mg/L, then solution pH adjustment to 7 or so can be directly outside. 2 membrane enrichment ratio on the membrane flux
control waste water within 50 times more concentrated than that of filtration membrane flux, more than 50 times more concentrated than, membrane flux decline sharply. When wastewater concentrated nearly 50 times, suspended membrane filter components, will shift to the reaction tank Ⅱ concentrate of middle trough, dissolved in HCl Ni ( 哦) 2, the generated NiCl2 back production processes using again. 3 processing economic benefits
according to the result of the productive test, 1 t nickel electroplating wastewater treatment unit consumption quota are shown in table 1. 61 yuan; In addition, the treated wastewater can send before processing recycle. Wastewater treatment 1 t, every day in wastewater treatment (300 t According to the 300 d) More than 80000 yuan, investment costs can be in about half a year to recover.