Research And Application On The Treatment Of Chor-alkli Industrial Wastewater By Coagulation Sedimentation-hydrolysis Acidification-BIOFOR Filters Combined Process

Characteristics of chlor-alkali industrial waste water is a big waste water quantity change, high concentrations of pollutants, can poor biochemical, poison more inhibited the growth of the aquatic life. This topic mainly takes a jiangxi chemical industry co., LTD. Alkali synthetic wastewater as the research object, the chlor-alkali production waste water comprehensive wastewater mainly comes from the workshop, absorbs wastewater, including chemical hydrogen silicone exhaust desulfurization dusting waste water, strong water stations concentrated water,2-methyl alcohol production wastewater,3-chloropropionic acid production wastewater and alkali waste water, trichloroethylene production wastewater and domestic sewage, etc.The chlor-alkali comprehensive waste water main pollution factor of CODcr and SS, NH3-N, etc, according to the measured, wastewater pH of2～6, CODcr is190～240mg/L, SS for200～300mg/L, NH3-N of45～60mg/L, the water temperature is30～40℃. Based on the characteristics of the wastewater, use "hydrolytic acidification+coagulation sedimentation+BIOFOR filter" combined technology to deal with the waste water, through the debugging and running characteristics of test in laboratory and engineering research, the results show that:1、The experimental results showed that:control coagulation precipitate initial pH of8.0, PAC dosing quantity is400mg/L, PAM dosing quantity is4ml/L, slow mixing time for30min, on this condition, SS removal rate up to93.6%; after coagulation, anaerobic, the CODcr removal rate remained at23.0%～54.7%and NH3-N removal rate is16.9%～20.6%; Finally, aerobic, CODcr removal rate to maintain between41.5%～52.1%, NH3-N removal rate is53.5%～68.7%.2、Engineering debug show that:Coagulation precipitation of optimal parameters for the initial pH of8.0, PAC dosing quantity is400mg/L, PAM dosing quantity is4ml/L, coagulation sedimentation tank effluent CODcr concentrations between120～175mg/L, CODcr removal rate remained at32.0%～51.2%.Hydrolysis acidification reactor was inoculated with anaerobic digestion sludge and domesticated. The early start, the basic without removal of CODcr effect, after running, CODcr removal rate remained at11.9%～11.9%, hydrolysis acidification of CODcr removal rate is lower; NH3-N removal rate within21.8%～39.3%, hydrolysis acidification of NH3-N removal efficiency is better. Biochemical BOD5/CODcr of wastewater increased from an average of0.284to0.389, improve the alkali wastewater biological sex, and draw a comprehensive waste water degradation alkali hydrolysis acidification pool dynamics equation:V=dS/dt=2.26(QSi/V)/[9.56+(QSj/V)].BIOFOR filter adopts hanging membrane directly. The early start, the CODcr removal effect is poorer, effluent CODcr concentrations above200mg/L, even higher than the inlet concentration, after running, CODcr removal rate was53.2%-53.2%, the SS removal rate over60%, NH3-N removal rate is42%-58.6%, effluent CODcr concentration maintained below100mg/L, SS concentration is less than50mg/L, occasionally NH3-N concentration is higher than15mg/L, but most of the time, NH3-N concentration is lower than15mg/L, the minimum of NH3-N in water is7.8mg/L, the effluent water quality can be meet.Chlor-alkali comprehensive wastewater by the coagulation sedimentation+hydrolytic acidification+BIOFOR filter "combination process after processing, system to remain above75%, the removal rate of CODcr of SS removal rate up to80%above, the NH3-N removal rate over70%, the highest of82.8%, effluent water quality meet the "standard of sewage comprehensive discharge"(GB8978-1996) level of emissions standards.3、Through calculations, the process of chlor-alkali integrated wastewater treatment cost about2.45yuan/t.