Studies On Treatment Technology And Processing Of The Dispersed Swine Wastewater

The dispersed swine wastewater is the wastewater produced by smale scale hoggery, where the pigsty is built in the farmer's yard and the scale of raising scale is less than 200 pigs.Due to the lack of economic treatment techniques, large amount of hoggery wastewater is drained to surface water body without any efficient treatment, thus resulting in severe water pollution. This issue has become cruisal on the way of developing the new countryside.This research studied the typical dispersed hoggery wastewater of the southern hilly area, firstly, deeply investigated the characteristics of drainage of the dispersed hoggery of which raising scale is less than 200 pigs. Secondly, based on the understanding of the disperse characteristic of the pollutants, combining with the fluid mechanics,the principles of chemical reaction engineering, developed the device of Intermittent crisscross flow liquid-liquid separation,efficiently decreased the loads of pollutants in the wastewater,realized the resource-oriented untility of pollutants at their source.Focusing on the wastewater produced by dispersed hoggery in rural area, integrated with the principles of fluid mechanics, biology and ecology , considering the feasiblility of the economy, operation and management, developed the integrated process composed of source separation technology-NBSFAOSP-constructed wetland.Optimized the parameters of hydraulic and the NBSFAOSP operation for the anaerobic unit in NBSFAOSP of the integrating processing, studied the even distribution of the manmade wetlands and the results using red soil and steel slag which are cheap and easy to get at local market as the substrate of the manmade wetlands.Adopting some methods such as ion chromatography?Fluorescent Spectromet?ultraviolet spectrometry, analyzed the rules of migration and transformation of DOM in the integrated treatment processing of the dispersed hoggery, initiated the discussion of the capabilities of the integrated treatment processing of the dispersed hoggery.The conclusions of this research are as the following:(1)In Hunan Province, hogwash and home-made forage is adopted by the dispersed hoggery to feed the pigs, rather than the standard forage. The water quality parameters of the wastewater are: COD is 8000?18650mg/L?pH is 7.0?8.7?TN is 720?1470 mg/L?TP is 35.4?165.7 mg/L.(2)Based on the understanding of the discharging characteristics of the source pollutants of the dispersed hoggery, adopted the processing of dry cleaning manure, decreased the loading of the treated wastewater efficiently by adopting the pollutants'source separating techniques, such as solid-liquid separation,liquid liquid separation, resourse utilization of pollutant,etc. realized the resource-oriented utility of the pollutants. Treated by the pollutants'source separating techniques, the water quality parameters of the dispersed hoggery wastewater are: COD 1200?1800mg/L?pH 7.0?8.7?TN 280?420 mg/L?TP18?28 mg/L.(3)The findings of study the configuration of anaerobic reactor of NBSFAOSP are:Pushing flow regime is presented generally in the anaerobic unit of HABRreactor, The capabilities of the cofiguation are excellent,The percentage of physical dead corner is about 9%, However, the the increasing of the isolated units, the flow rate in the reactor has increased, therefore, results in the increasing of the dhydraulic dead corner. Integrated the economic factors and considered the energy efficiency and effective capacity utilization, HABR reactor with three units has been adopted as the initiated anaerobic treatment unit of the NBSFAOSP processing.(4)Under normal temperature and 36h HRT, if the inlet water is real dispersed hoggery wastewater, it will take anaerobic unit,HABR, of NBSFAOSP 4 weeks to finish the initiative operation. When the operation is stable,the index such as COD, SS and so on, can meet the discharge standard of?mass Disharge standard of pollutants for livestock and poultry breeding?(GB18596-2001), but the efficiencies of removing nutrition elements, such as N and P, are not ideal,can not meet the standard. Furthermore, the impact resistance of the reactor shows that the capability of the cushion of pollutant load of the 3 reactors has increased, the filling could stablize the biomass in the wastewater very well.(5)After 100 days operation of the NBSFAOSP processing, the operation results reveal: Average values of the discharge are: COD 100 mg/L?NH₄⁺-N 66mg/L?TP is 13 mg/L?SS 15 mg/L. The values of COD?NH₄⁺-N and SS are lower than the discharge standard for the mass breeding?Disharge standard of pollutants for livestock and poultry breeding?(GB18596-2001). Phosphor removing and advanced stable treatment will need support of the successing treatment processing. Single factor experiment results show: under the operating of the single water quality, controlling the concentration of the dissolved oxegen within a reasonable range is the crucial factor of the N removal technique. Meanwhile, the study also finds: the other two key factors affecting the removal efficiency of TN are the C/N of receiving water body and the adding ratio of wastewater. The experiment results are: the concentration of the dissolved oxgen of the dispersed hoggery wastewater should be 2.4 mg/L, the C/N should not less than 6,water distribution ratio of the last step should not over 15%.(6)The operation of constructed wetlands presents: As the substrate of the wetlands, the red soil and steel slag have great absorptivity of phosphor, so they could be the prior choice for the hilly area of southern China. Using subsurface flow constructed wetland formed by red soil and steel slag, TP in effluent can be below the 5mg/L. TP removal rate wasn't obviously influenced with the change of water temperature. Assist to artificially supply oxygen, the nitrogen removal capabilities of wetlands can be increased by 15%.(7)The operation results of the processing which integrated source separating technique, NBSFAOSP processing and constructed wetlands reveal that the index of COD?NH₄⁺-N?TP and SS in the discharge are better than the discharge standard of?Disharge standard of pollutants for livestock and poultry breeding?(GB18596-2001) The analysis of ion chromatography.hows that the total amount of organic acid as reached the highest point at NBSFAOSP process anaerobic stage 2h, at this point, the content of propionic acid reach the highest point too. With the proceding of the reaction, the content of acetic acid has gradually increased. Small molecular organic acids will be degradated rapidly in the aerobic stage.The anlalysis of fluorescence spectrum presents that there are apparent correlationship between the peak intensity of Synchronous flourimetry 277nm and the concentration of organic acid in Anaerobic hydrolysis stage; plastein are the predominant organics in the wastewater in anaerobic phase; microorganism can degradate the organics rapidly in aerobic phrase, fulvic like in the wastewater will increase at the same time. The changes of SUVA254?E253/E203 present that the aromaticity and unsaturation of the dissolved organics in the wastewater will increase with the increasing of the hydration time, the species and amount of the substituents of the aromatic ring will increase too. The decreasing of the stability of aromatic ring material will benefit the removal of organicsin in the succesding aerobic phrase.