| The mustard wastewater of Fuling is one of the high-salinity wastewater,with the characteristics of high salt content,high organic loading,elements of N, P have far exceeded standard,the range of pollution is extensive,the distribution is more dispersed and so on. All these bring a serious threat and breakage to the environment ang ecological of the Three Gorges Reservoir Area. At the present time,The treatment methods of high-salt wastewater mostly include physical methods,Chemical methods and biological methods, However, due to the treatment methods of physical,chemical operating costs higher,not synchronized with the local economic development,and the treatment effect alone is not ideal, it is easily cause secondary pollution also difficult to promote in practice, but the biological methods for economic and efficient characteristics in the high salt wastewater treatment has been widely favored in. In this study, as the research object to mustard wastewater of farmers' mustard plant in Zhen xi Town, Fuling. With local conditions, to carry out based on economic, environmental, and operable, integrated wastewater treatment effect on mustard good method or process, of great practical significance and long-term economic benefits.Aim at the characteristics of mustard wastewater, In this paper, mustard wastewater will be treated by physico-chemical, electrochemical and biochemical methods of combining. Above all. the mustard wastewater will be pretreatment with coagulating sedimentation method,mainly to remove suspended solids in waste water, some organic matter and P, increased biodegradability; Secondly, adopt anaerobic fermentation of waste water to remove most of organic mustard and some of the N; Ultimately, adhibit electrodeSBBR system for the integrated treatment of pollutants to the mustard wastewater, and investigate technological factors affecting each unit of the system, access to key parameters of the combined process. The main research conclusions are as follow:(1) In the process of mustard wastewater by coagulation treatment,first of all,Screened out the best coagulant for mustard water turbidity removal of suspended solids,followed by the single factor of coagulation tests, get the best coagulation parameters:①The size of treatment in the order with coagulation of the effect of mustard wastewater, coagulant dosage> coagulant type> stirring speed> settling time.When the CaO dosage is 700mg/L,the stirring time is 30min at the speed of 250-300r/min.removal of turbidity in the same experimental conditions close to aluminum accumulation dosage 900mg/L of the treatment effect;②Select PAC as a coagulant, before and after in PAM (coagulant) into waste water treatment.the change has little effect; and select CaO as a coagulant in waste water with the automatic adjustment function of pH, as a coagulant aid by PAM can significantly improve settlement efficiency, save the amount of coagulant to reduce wastewater pungent odor, improve the biodegradability of mustard, meanwhile COD and TN removal rate based on the PAM without increased 16.57%, respectively,18.66%; The treatment effect was better than the treatment effect of PAC, of mustard pretreatment of wastewater with good results;③Through the test card of the CaO + PAM effect of the pretreatment of mustard wastewater, on COD, TP, turbidity, and had a certain pungent odor removal, to reduce the burden for follow-up treatment of mustard wastewater, on the one hand it's can improve the production environment, on the other hand the formation of the floc settling larger deposits can develop easy to be recycled into feed or organic fertilizer, and can bring good economic value, with good promotional value.(2) In the process of mustard wastewater treatment by anaerobic biological,put the water index of coagulation and sedimentation of process (1) as the water index of anaerobic biological treatment,through static test of the anaerobic biological treatment of mustard wastewater known,①Inoculate anaerobic digestion sludge of sewage treatment plants and with mud mustard factory outlet(1:1) as the anaerobic fermentation sludge of anaerobic fermentation. It is can produce more gas and hast he highest removal rate of COD;②The size of the order in experimental factors on the mustard wastewater COD removal efficiency of anaerobic fermentation as folw:temperature> volume load> pH> sludge concentration. By single factor test to determine the optimal experimental conditions, that when the temperature is 40±2℃,volume load is less than 1.24 kgCOD/(m3.d),water pH is 6.5～7,at this time, COD removal efficiency stabilized at 63% or more;ln anaerobic fermentation tests can be founded.system on the removal rate of COD decreased with increasing salinity,when the salinity is not higher than 15g/L,COD removal rate can be stabilized at 80%;④With mustard wastewater containing concentration of salt is 14.78g/L to acclimated anaerobic sludge, when used to process salt concentrations higher than 14.78g/L of mustard waste water,Vmax values decreased, this shows an increase with salinity, NaCl inhibition on COD degradation in strengthening; when used to manage salinity is less than or equal to 30.24g/L of mustard water, salt (NaCl) on the anaerobic biodegradation of COD anti-competitive inhibition of the reaction kinetics equation as:V=(?)=(?), the inhibitor constant KI=25980mg/L;⑤When the mustard water salinity is less than 30.24g/L, its response type is non-competitive inhibition, when the salinity was 35.42 when the anti-competitive inhibition, the inhibition increased with the salinity maximum.(3)Through dynamic study in a pilot suggests that, after a period of time of the system stable operation, the removal rates of COD, TN, TP were 75.01%,13.64% and 6.92% in the system. Although there is no treatment effect of static small scale, but the overall trend is consistent with the small test results.(4) Put the indicators of anaerobic fermentation of the effluent water treatment systems in (3) as indicators of SBBR, compared to the effect of electrodeSBBR and SBBR in mustard wastewater treatment system:①Under the same conditions, the COD removal is better in ElectrodeSBBR system than the single run SBBR system; system and the removal rate of COD values decrease with the mustard SVI sludge in wastewater rising salinity, when the COD removal rate dropped to 44.85% in SBBR system,while the removal of COD still can achieve 67.13% in electrodeSBBR system, and the rate of reduce more slowly in the SBBR system; When the SVI value of SBBR system from76.33mL/g down to 45.55mL/g, the ElectrodeSBBR system SVI values remained at 50.33mL/g or more, and running angle stability, strong resistance to shock loading;②Through the Comprehensive Comparison of six treatment condition, by X2 test,it's can be seet han different treatment conditions were significantly different on the various pollutants in electrodeSBBR system, the best process condition will be determine in the electrodeSBBR system of mustard wastewater, when the time of HRT is 14h,the anaerobic/anoxic is 2.5h,aeration is 10h,anaerobic is 1.5h,the system of COD, TN, TP removal rates were 83.26%,70.98% and 52.56%;③When electrodeSBBR system stable operation under the best condition,determine the best test of the system factor as, the current strength of DC is 80mA,the best biofilm density is 35%～50%,the best concentration of DO is 5mg/L. |
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