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In recent years, swine wastewater pollution problems caused by more and more scholars are highly valued. Due to its large amount of pollution, the process is not complete, the water environment has become an important source of pollution. Swine wastewater mainly from animal manure, urine and farm rinse water. Its organic matter, suspended solids and phosphorus levels were higher than China's \Swine wastewater toxic organic pollutants can be divided into traditional and emerging pollutants, contaminants such as lipids, including traditional fats, fatty acids and sterols, volatile malodorous compounds include aromatic phenolic compounds, nitrogen-containing heterocyclic compounds, volatile fatty acids and mercaptans; some emerging contaminants, such as in pig diets of veterinary antibiotics are also detected in the wastewater. According to the survey, pig antibiotics added during the excess is widespread in China each year 80,000 people died as a direct abuse of antibiotics, and the abuse of pigs than people in serious condition hundred thousand times, kill the pig countless. Since most farms treatment facilities inadequate or not addressed, these pollutants will be discharged directly into rivers, lakes and the nearby waters, causing serious environmental pollution of water bodies. According to available information, research on swine wastewater mostly concentrated in the traditional analysis of pollutants, such as chemical oxygen demand CODcr, biochemical oxygen demand BOD5, TN TN and TP TP and so on. Wastewater quality characteristics with special organic pollutants rarely been reported. In this thesis, swine wastewater characteristics and distribution of organic matter carried out a comprehensive analysis to clarify the composition of dissolved organic matter in wastewater existing differences, as proven in the process of its degradation behavior provides a scientific basis. While special odor compounds and pollutants such as long-chain fatty acids analysis methods were optimized, and the establishment of veterinary antibiotics in wastewater multi-residue detection method. Studied the various aspects of wastewater treatment pollutant removal efficiency and long-term trends in control. Depth study of refractory macrolide antibiotics degradation of natural light and take advantage of the information obtained by mass spectrometry identification of its degradation products one by one, through a long-term raw material and product quantitative monitoring to simulate the degradation under natural conditions Trends for the study of antibiotics in the natural environment of migration and transformation provides a theoretical and practical basis. The main research contents can be divided into the following areas: 1. Swine wastewater treatment system and its distribution characteristics of organic matter removal efficiency of swine wastewater and water samples from some pig farms, wastewater treatment process through improved purification then back for farmland. The treatment process includes solid-liquid separation, acidification regulation, anaerobic fermentation, bionic natural oxidation and rapid infiltration and a series of measures. Pollutants in the treated wastewater volume decreased by 90% or more, to meet emission standards. Because swine wastewater organic ingredients differences, for a more comprehensive grasp of its organic composition, we use three typical grouping method, the complexity of the wastewater in accordance with different molecular weight organic compounds, and charge characteristics of different polarity into a series of different structures, properties relative to a single material components, according to its spectral and mass characteristics were studied. Through microfiltration and ultrafiltration technology will be divided into six different wastewater molecular weight components, M1 (without separation of raw water samples), M2 (less than 1.0μm total composition), M3 (less than 0.45μm solubility component), M4 (between 0.45μm and 1.0μm between the micro-soluble fraction), M5 (less than 1 KDa ultrafiltrate) and M6 (between 1 KDa and 0.45μm between colloidal concentrate). The characteristic UV spectrum and UV absorption value SUVA analysis, with the UV absorption wavelength increases, the component SUVA absorption values ??with consistent decreasing trend: 210 nm gt; 254 nm gt; 280 nm. SUVA absorption of different molecular weight components Value size: M5 gt; M4 gt; M6 gt; M2 gt; M3. infrared absorption spectrum of each component of the similarity, contain 9 characterized in spectral band, the band intensity is slightly different. According to the charge characteristics of different materials, we use XAD-8 resin and anion exchange resin dissolved organic matter (DOM) component (M3) is further divided into six components: hydrophobic acid (HoA), hydrophobic bases (HoB), hate Water resistance (HoN), hydrophilic acids (HiA), hydrophilic bases (HiB) and hydrophilic neutral (HiN). By UV absorption spectroscopy, UV absorption at 200nm to 350nm districts have four main absorption band, while the important features organic produce spectral band at 254 nm and 280 nm. Most of the organic matter present in the hydrophobic acid, hydrophobic and hydrophilic neutral alkali component. The infrared absorption spectrum of the different components vary greatly, mainly observed spectral bands 9, which is the measured molecular weight component 9 is not entirely consistent infrared bands. The results show that the wastewater containing high concentrations of protein and amino acids, and the PH bond stretching vibration reveals the presence of phosphorus-containing compound. Polarity to the materials, we will soluble organic matter (M3 and M5) is divided into non-polar, weakly polar and polar three different components. After each component sample enrichment, purification, gas chromatography - mass spectrometry results, major non-polar components in alkane-based, and thus infer wastewater containing soluble non-polar organic carbon paraffins. The M3 samples, the polar fractions dominated by aromatic phenolic compounds, accounting for more than half of the entire composition. Phthalic acid esters (PAEs) and other non-polar lipids M3 components in the sample 15% of the total, while the sample in M5 and 50% or more. In the non-hydrocarbon components (i.e. polar component), the sterol and the fatty acid composition of lipids account for 70% or more. Meanwhile, in the non-hydrocarbon components have been detected in the presence of six drugs, which for wastewater antibiotics studies provide useful information. 2 classes and long-chain fatty odor pollutants in the water treatment system to remove odor class distribution and the distribution and removal of organic compounds: Through the optimization of pretreatment conditions, headspace solid phase microextraction (HS-SPME) and solid phase extraction (SPE) Comparison of two kinds of enrichment methods, to establish a pig malodorous substances in wastewater (4 - methyl phenol, 4 - ethyl phenol, indole and skatole) measurement method. SPME headspace SPME using the PA, the best extraction conditions were: water pH = 4, ionic strength of 30% (sodium chloride), water bath temperature of 70 degrees, the extraction time of 30 minutes, parsing temperature of 260 degrees, resolution time 3 minutes. Solid phase extraction using Tenax adsorption fillers, homemade solid-phase extraction column, optimum extraction conditions were: water pH = 7, ionic strength of 30% (sodium chloride), the sample through the column, the use of dichloromethane and hexane The mixed solution (1:2) as an elution solvent. Using the best pre-treatment conditions, the detection limit of the target range of 0.09μg L-1 to 1.48μg L-1, and the relative standard deviation of less than 15%. Two kinds of pre-treatment methods are compared on a number of indicators, such as the selectivity, sensitivity and accuracy of such quantification. The results showed that headspace SPME method detection limit of quantitation (LOQs) and precision are better than solid-phase extraction method. However, because of its solid-phase extraction method was simple, stable characteristics nonetheless effective semi-volatile malodorous substances in wastewater qualitative and quantitative method. Water through the different treatment of the components of malodorous substances, odor indole compound in the biological treatment process to remove a part, and phenolic compound removal efficiency is low, can not be effectively removed. Residual toxicity of phenolic compounds with the effluent discharged into the environment will give harm to human health. The distribution of long chain fatty acid compounds and removal: Using XAD macroporous resin adsorption, gas chromatography mass spectrometry (GC-MS) detection technology, the establishment of non-volatile in swine wastewater Determination of long chain fatty acids. Experimental results show that the essential fatty acids contained in the wastewater (relative percentage of all fatty acids) of palmitic acid (C16: 0) and stearic acid (C18: 0) are two, but also the nature of the most common long-chain fatty acids. As one of the highest levels in waste water saturated acid, stearic acid concentrations reach 1.4 mg L-1. Meanwhile, some one yuan unsaturated fatty acids, such as (C16: 1, C18: 1 and C20: 1) in sample handling process can also be eluted and detected in higher concentrations. Fatty acids in the wastewater treatment process have different performance behavior of most fatty acids in the anaerobic biological treatment process is not effectively removed, and nearly half of the fatty acids in the natural oxidation process has been removed (water W2), and in the next rapid infiltration system almost completely removed (water W3). The results show that the wastewater treatment process for the removal of fatty acids significantly. 3 veterinary antibiotics and removal efficiency of pollution established groundwater, lakes and swine wastewater in a variety of veterinary antibiotics, such as tetracycline (TCs), sulfonamides (SAs), quinolones (FQs) and chloramphenicol (CAPs) and other multi-residue detection methods. Solid phase extraction using the optimized combination of pretreatment liquid chromatography tandem mass spectrometry instrumentation (SPE-LC/MS/MS) for trace analysis of antibiotics. Meanwhile, the flight time by liquid chromatography mass spectrometry (LC-ToF-MS) and LC-MS/MS performance comparison of the two instruments, the establishment of eight water penicillin (PCs) for rapid detection. Both instruments have a fast and simple operation. In the determination of penicillin, LC-MS/MS than LC-ToF-MS detection limit lower, greater accuracy, thus preferred for quantitative analysis. Meanwhile macrolide antibiotics such as azithromycin, erythromycin and other existing methods used for analysis. To tetracycline, sulfonamides, chloramphenicol and other quinolone and measurement results show that the groundwater in summer farm, near the lake, swine wastewater effluent and influent concentration range containing antibiotics were 1.6-8.6,5.7-11.6,7.9-1172.3 and 8.5-21692.7 ng L-1, respectively 2.0-7.3,6.7-11.7,5.8-409.5 winter and 32.8-11276.6 ng L-1. Additionally, amoxicillin, azithromycin and erythromycin are also detected in the wastewater , in concentrations of 540 ng L-1, 602 ng L-1 and 456 ng L-1. All samples (groundwater, lake water, wastewater and effluent) antibiotics analytical method detection limits were lower. Although detected in wastewater and environmental water samples were lower concentration of antibiotics, they remain in the environment on human health and long-term toxic effects must pay close attention. 4 macrolide antibiotics in the water environment photodegradation (simulated sunlight and natural light) study investigated the photocatalytic process removes macrolide antibiotic azithromycin possibilities, from light degradation kinetics and photolysis products of the environment perspective of the ongoing effects of the degradation mechanism. Analyzes of water samples on six different simulated degradation rate of azithromycin effects: high purity water (HPLC water), surface water (Freshwater, FW), plus surface water nitrate (FW nitrate), humic acids (Humic acids, HA), plus nitrate and humic surface water (FW nitrate HA), swine wastewater (piggerywastewater). The results show that azithromycin photodegradation process follows a kinetic equation: FW nitrate HA gt; HA gt; piggery wastewater gt; FW nitrate gt; FW gt; HPLC water. Photodegradation process produces seven kinds of degradation intermediates, the use of high pressure liquid chromatography with quadrupole, time of flight mass spectrometry in the positive ion mode (UPLC-() ESI-QqToF-MS2) of seven kinds of possible degradation product (TP1, TP2, TP3, TP4, TP5, TP6, and TP 7) were identified. The measured quality of the product number and the reference contrast, to obtain the exact mass, and may be provided with the software elements and saturation contrast, with the chemical structure of the original seven kinds inferred structure of degradation products. The results show that the degradation pathway of azithromycin can be summarized as follows: Product 1 and Product 2 comes mainly from sugar ring azithromycin at different income lost on a methyl group, and the product 3 is in the product on the basis of an amino sugar ring opening deoxy and deoxy-income , the product 4 is a product 2 and the other sugar and loss of one methyl group on the ring result. Of compound 5 and 6, respectively, from the drop azithromycin and erythromycin deoxy sugar, amino sugar, and the product composition of 15 7 macrocyclic ring alicyclic ring, may be derived from the product 1-6, may also be part of the direct removal from the product 1 bis sugar derived. Using high pressure liquid chromatography with tandem quadrupole mass spectrometry (UPLC-QqQ-MS2) in multiple reaction monitoring mode for seven kinds of products relative quantitative analysis method to optimize the product obtained seven kinds of multiple reaction monitoring methods. Different samples of the product matrix in the light of 1-5 basic produced within 1 hour and within 10 hours of continuous exposure to achieve maximum concentration. The product 6 and 7, the product generation time differences, the maximum concentration is obtained before the irradiation 30-50 hours. Most of degradation products after 70 hours after irradiation has not been completely degraded, especially in the product 1 and the product 6 swine wastewater after 100 hours Irradiation matrix can not be degraded even after completely. Therefore, although the degradation products generated quickly, but the duration is quite long. In order to explore the actual environment migration and transformation of antibiotics, we will azithromycin added to water samples collected by the natural light to give azithromycin under natural conditions of the environmental behavior. The results show that azithromycin in natural light irradiation also follows a kinetic equation, and the half-life of 5.4 days, over 70% of the azithromycin in the eight days under natural conditions is removed. However, conventional wastewater treatment process is far less than the hydraulic retention time 8 days, which is the removal of azithromycin is not enough. After a half-time exposure, the product 1 and the product 6 also appear in the water sample, and after 35 days natural light can not be removed. Visible, Environmental Water azithromycin in natural lighting conditions, the degradation rate is very low, and its degradation products in the environment for a long duration. Azithromycin and its degradation products environmental toxicity and risk should be cause for more concern. Such studies migration and transformation of pollutants antibiotics can provide a theoretical basis for environmental risk assessment.
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