| TNT(2,4,6-trinitrotoluene) is an important material in military area. TNT wastewater from manufacturing process and disposing process is hardly biodegradable. The technique of electro-hydraulic discharge (EHD)developed in recent years including many effects such as high temperature pyrogenation, photochemistry oxidation, cavitation degradation, super-critical water oxidation, has advantages of normal temperature and press, high efficiency, no-selectivity, no-second pollution, low energy, and is efficient in disposing dis-biodegradable wastewater. The experiment installation of electro-hydraulic discharge was designed and established, and the influence factors, degradation mechanism, joins techniques, product analyse of TNT wastewater treatment by EHD was investigated. The results are as following:①The experiment installation of electro-hydraulic discharge was designed and established detailedly, and TNT degradation rate of different installation was compared. Power supply can generate pulse high voltage which ranged from 0 to 100kV. The grounding net was designed and laid, and grounding resistance was 0.86Ω, which can guarantee safe during the course of discharging. Stainless steel reactor (level and uprightness discharge) and 45# carbon steel reactor were designed and machined. Four type of electrode, such as point-point, point-plane, points-plane, hollow electrode, and three electrode material such as stainless steel, copper, 45# carbon steel were designed and machined. The results are as following: TNT degradation rate of 45# carbon steel reactor was better than stainless steel one's; TNT degradation rate of three kinds of electrode materials which were investigated was copper >45# carbon steel > stainless steel. TNT degradation rate of points-plane electrode was highest, and the point-point electrode's and point-plane electrode's take second place, and hollow electrode's was lowest. With the improvement of electrode inslution length, the bare area of electrode decreased, TNT degradation rate increased. TNT degradation rate of uprightness discharge was better than level discharge's.②The EHD wastewater treatment apparatus was used to degrade TNT wastewater by using 45# carbon steel, level discharge, point-point electrode, and influence factors of TNT degaradion , kinetics and energy efficiency were investigated. The results showed: When TNT concentration was 50.00mg/L volume of wastewater was 7L, after 300 discharges TNT degradation rate was 87.00%, TNT concertration decreased to 6.50mg/L. after 500 discharges TNT degradation rate was 91.20%, TNT concertration decreased to 4.40mg/L, reached national discharge standard. TNT degradation reaction by EHD followed appearance first order kinetics, and the energy of activation was 14.5kJ/mol. The energy efficiency is high, G value reached to 6.56×10-2～9.33×10-2 molecule/heV.③Mechanism of EHD degrading aqueous organics was investigated. With the analysis of EHD principle and course, TNT degradation mode of EHD was summarized. The effects of EHD, such as high-energy electron, high temperature pyrogenation, oxidation of H2O2 and O3, supercritical water and ultrasonic cavitation, shock waves, UV photolysis, oxidation of active particle. In addition, the spectrum of EHD streamer and spectrum of active particles during the experiment was tested.④Degrading TNT wastewater by EHD/Nanosized TiO2,and EHD/aerate was investigated. Nanosized TiO2 powder prepared by sol-gel method was characterized. TNT wastewater was degraded by EHD/Nanosized TiO2 Photocatalysis and influence factors were investigated. Results showed that adding Nanosized TiO2 to EHD can improve TNT degradation rate. When TNT concentration was 90.00mg/L,volume of wastewater was 7L, discharge times was 300, TNT degradation rate by EHD was 63.00%, adding 0.035g/L nanosized TiO2 to EHD, TNT degradation rate reached 90.47%. According to the EHD experiment apparatus, aerate apparatus which can supply air or O3 was designed and machined. TNT wastewater was degraded by EHD/ air or O3, and influence factors were investigated. When TNT concentration was 50.00mg/L, volume of wastewater was 7L, discharge times was 300, ventilation electrode (medium-hollow electrode), TNT degradation rate by EHD was 59.80%, TNT degradation rate by EHD/air was 63.12%, TNT degradation rate by EHD/ O3 reached 82.95%.⑤Degrading TNT wastewater by EHD/Fenton reagent was investigated, and the EHD/ Iron scraps degrading TNT wastewater was put forword. TNT wastewater by EHD/Fenton reagent was reaseached, and influence factors were investigated. Results showed that adding Fe2+ or H2O2 lonely to EHD cann't improve TNT degradation rate, but adding Fe2+ or H2O2 together ( Fenton reagent ) to EHD increase TNT degradation rate greatly. Under the same experiment condition, TNT degradation rate by EHD was 63.00%, while adding FeSO4 25.00mg/L,H2O2(30%V/V)0.50ml/L to EHD, the degradation rate by EHD/ Fenton reagent was 79.38%. TNT wastewater by EHD/ Iron scraps was reaseached, and influence factors were investigated. Results showed that adding Iron scraps to EHD can improve TNT degradation rate greatly. Under the same experiment condition, the degradation rate by EHD was 63.00%, While adding iron scraps 40.00g/L, the degradation rate by EHD/Iron scraps was 92.16% , TNT concerntration was 3.92mg/L, reached national discharge standard. Because of the high degradation rate of EHD/Iron scraps , the less discharge times, and the more use times of iron scraps, the EHD/Iron scraps has more protential to be used in practice. Therefore, in this paper, the Iron scraps internal eletrolys was recommended to be the best join techics of EHD.⑥The change of CODcr, BOD5 during the course of EHD was investigated, and the degradation products were analyzed by GC/MS, and the possible degrading route of TNT was discussed. Results showed that after 300 discharges EHD reached 97.36% in TNT degradation and 34.29% in CODcr removal. That is to say, during the course of EHD, TNT haven't been mineralized tollaly, many arganics still existed in the wastewater. The BOD5 of TNT wastewater before discharge was"not examined", the BOD5 after 50 discharge increased. This showed the biograble argaices appeared after discharge. The GC/MS spectum showed that TNT was degraded by EHD, the degradation products includeed organic substance containing benzene(Benzene, 1,4-dimethyl, Styrene) and aliphatic hydrocarbons (Tetradecane, Heptadecane).
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