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Aromatic carboxylic acid production process will generate a lot of high concentration organic wastewater, wastewater with high concentrations of pollutants, changes in water quality and quantity, and more types of pollutants and the pH fluctuation range is more difficult one of the petrochemical waste water, if its direct emissions, will be on the aquatic ecosystem damage, it must be dealt with. In this paper, the Fenton oxidation PTA refined wastewater study, the effects of pH, FeSO4 · 7H2O dosage, dosage of hydrogen peroxide, hydrogen peroxide dosing method and reaction time conditions on the treatment effect, combined with orthogonal to the test, and in consideration of the actual production, the preferred operating conditions: pH 3.0, one-time dosage of hydrogen peroxide for 20 mL / L FeSO4 · 7H2O amount of 1.5g / L and aeration time of 3h, the operation temperature of 55 ° C. Under these conditions, the PTA refined wastewater COD removal rate reached 65.5%. Contrast the various types of macroporous resin pretreatment PTA refined wastewater treatment effect, the choice of macroporous resin HPD-950 type. Investigated the amount of resin is added, adsorption temperature, adsorption pH and oscillator strength of macroporous resin adsorption process, the lower the temperature, pH value lower oscillation intensity beneficial to the adsorption process; macroporous resin wastewater treatment compared with good operating conditions: the amount of resin is added as 8 g / L, the oscillation time for 2.5h, the adsorption temperature is 25 ° C, oscillation intensity of 200rpm and a pH value of 4. Investigated by dynamic experiments industrialization Follow duration, running time and the reproduction time of the effect of resin adsorption, obtained optimum operating conditions: duration 30 min, the run time of 50h, the reproduction time for 30min, PTA refined wastewater COD removal rate can reach more than 90%. On this basis, the use of ion exchange method the PTA refined wastewater deepening processing, PTA refined wastewater 3 metal ion content standards. Found the LS101 more appropriate PTA wastewater processing, when the added amount of the resin for 5 mL / L wastewater, the wastewater is in the removal of metal ions reached 89.7% by the screening assays of the resin. As the temperature increases, the ion exchange reaction speed to accelerate exchange capacity change is also accelerated, reduce the time required to reach equilibrium, the resin structure will be small variations when the temperature is too high, thus affecting the ability to exchange, so the temperature of the system exceeds 45 ° C , the efficiency of the resin is significantly reduced. We chose 45 ° C for optimal temperature. Hydrochloric acid regeneration can restore the activity of the unsaturated resin, the use of static immersion Renewable dosage: LS101 amount of resin only 90mL: 60mL.
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