[VOCs and Odors Control and Development in Pharmaceutical Fermentation Industry].

Volatile organic compounds (VOCs) and odors, which pose potential hazards to human health and the ecosystem, are two of the most important pollutants emitted from the pharmaceutical fermentation industry. Currently, basic research on the characteristics of the pollution and effective prevention technology for VOCs and odors emitted from the pharmaceutical fermentation industry are limited. Specifically, the pharmaceutical fermentation industry lacks adequate theoretical guidance on the supervision and control of VOCs and odors, and some companies even face relocations. Using the pharmaceutical fermentation industry as the study object, the pollution characteristics of VOCs and odors emitted from different production workshops, sewage treatment stations, and the disposal of pharmaceutical residues were assessed. Based on the studies above, the progress of research into representative control technologies were also reviewed systematically. For VOCs and odors control in the pharmaceutical fermentation industry, four suggestions for future research were proposed:① The production processes should be optimized, and the discharge of pollution should be reduced throughout the entire processes; ② Basic research should be carried out on the pollution characteristics of the VOCs and odors emitted from the pharmaceutical fermentation industry, and a rapid and effective method to trace the sources of VOCs and odors should be established; ③ A comprehensive evaluation of control technologies should be conducted, taking cost and efficiency into account; ④ Emission standards and technical orders for VOCs and odors in the pharmaceutical fermentation industry should be formulated and implemented immediately.

[Effects of Interaction of Ozonation and Coagulation on Coagulation Results].

Two strategies, ozonation-coagulation combination (OCC, ozone and coagulant dosed at meantime) and preozonation coagulation (PC, coagulant dosed after ozone died away) were used to treat synthesized water. Different effects of oxidation and coagulation, disinfection by-products formation potentials (DBPFP) in the same water were detected in order to study the influence of interaction of ozonation and coagulation (IOC) on treated water characteristics. Results show that there are remarkable differences between OCC and PC. IOC effects take place during OCC process, which results in variations of the distribution of hydrolyzed species of coagulant. And this is an important reason which impairs efficiency of coagulation. Turbidity after OCC was higher than that of PC. One of the main reasons is that ozone reduced the content of Alb species which was built during coagulant hydrolyzation. Cl-DBPFP in OCC outlet water were lower than those in PC because oxidized destruction of DBP precursors were enhanced by catalyzed ozonation by AlCl3 along with its other hydrolyzed species. Removals of MCAA and CF formation potentials by OCC were significantly higher than those by PC, MCAAFP were 5. 6 µg . L-1 and 16. 9 µg . L-1 respectively, and CFFP were 12. 5 µg . L-1 and 24. 1 µg . L-1 respectively. Coagulation results and DBP formations are significantly affected by interaction of ozonation and coagulation; and it should be a noticeable point of water safety if ozonation and coagulation are employed together. Thus times and spots between ozone and coagulant should be defined clearly in correlational researches and water treatment application.

[Removal of fluorescent whitening agent by hydrogen peroxide oxidation catalyzed by activated carbon].

Degradation of fluorescent whitening agent VBL in the processes of activated carbon (AC) and activated carbon modified (ACM) adsorptions, hydrogen peroxide (H2O2) oxidation, and hydrogen peroxide oxidation catalyzed by activated carbon were studied. Mechanism of the above catalytic oxidation was also investigated by adding tert-Butyl alcohol (TBA), the free radical scavenger, and detecting the released gases. The results showed that: the activated carbon modified by Fe (NO3)3 (ACM)exhibited better adsorption removal than AC. Catalytic oxidation showed efficient removal of VBL, and the catalytic removal of AC (up to 95%) was significantly higher than that of ACM (58% only). Catalytic oxidation was inhibited by TBA, which indicates that the above reaction involved *OH radicals and atom oxygen generated by hydrogen peroxide with the presence of AC. The results of H2O2 decomposition and released gases detection involved in the process showed that activated carbon enhanced the decomposition of H2O2 which released oxygen and heat. More O2 was produced and higher temperature of the reactor was achieved, which indicated that H2O2 decomposition catalyzed by ACM was significantly faster than that of AC. Combining the results of VBL removal, it could be concluded that the rate of active intermediates (*OH radicals and atom oxygen) production by ACM catalytic reaction was faster than that of AC. These intermediates consumed themselves and produced O2 instead of degrading VBL. It seemed that the improper mutual matching of the forming rate of activating intermediates and the supply rate of reactants was an important reason for the lower efficiency of ACM catalytic reaction comparing with AC.

[Effects and mechanism of catalytic decomposition of ozone by activated carbon].

Effects and mechanism of catalytic decomposition of ozone by activated carbon (AC) were studied by detection of residual components in released gas and temperature of reactor pole, and heat analysis through the ozone decomposition pole (ODP). Results showed that ozone could be thoroughly decomposed (removal rate was maintaining 100% all along the process studied) for 5 h under the condition of O3 12.89 mg x min(-1), 18 mm diameter glass tube was stuffed by activated carbon (made from coal, 2.0-2.5 mm diameter). The temperature of ODP was found rise during the treatment. The temperature became stable after quickly rise to 65-69 degrees C; and the CO2 output reduced with the stable temperature. The mechanisms of ozone decomposition were found including three parts. The first is catalytic decomposition by AC. AC enriches O3 and enhances O3 decomposition to form O2. The second is AC reaction with O3, which leads to destruction of the surface structure or group and output of CO2 and NOx are released with offgas. The third is temperature rising caused by heat production of CO2 and NOx formation according to the above two mechanisms, which enhances O3 thermal decomposition. Meanwhile, some basic design principles of ozone decomposition device were discussed.

[Study on removal of surfactant by activated carbon catalytic ozonation].

The anionic surfactant sodium dodecyl benzene sulfonate (SDBS) is employed as the target pollutant; the SDBS degradation in the processes of ozone (O3), activated carbon (AC) and activated carbon catalytic ozonation were studied. The impact of natural organic matter (NOMs) on the degradation of SDBS by catalytic ozonation was also investigated. Results show that: SDBS removal by using activated carbon catalytic ozonation is higher than that of using single ozonation or AC adsorption respectively; and the most effective time is the early 20 min when the concentrations of ozone and SDBS are relatively high. In the first 5 min (general hydraulic retention time), SDBS removals of the ozonation and AC adsorption were only about 17% and 12.2%, respectively; while the removal of catalytic ozonation reached 54.2% which was much more than the total removal of single ozonation and single adsorption, which showed significant efficiency of the catalytic ozonation. The mechanism of catalytic ozonation involves more radicals could be generated by ozone with the presence of AC; or much higher concentrations of both ozone and reactant would achieve, which enhances the reaction efficiency. Compared with the raw AC, AC experienced relatively long time and high concentration ozone treatment showed little effects on its decomposition efficiency of SDBS during catalytic ozonation. NOMs in the water samples decreased SDBS removals by catalytic ozonation; but the removals kept high under relatively low NOMs concentrations.

[Effects of polymer aluminum hydrolysis on phosphorus distribution in coagulation].

Coagulation treatment was conducted by using coagulants of different basicity (ratio of OH(-)/Al); contents,distributions and algal availability of phosphorus in water were studied before and after coagulation. Results show that: phosphorus removals and its distribution in water were markedly different according to the coagulant with different basicity used; Al(a) plays an important role in the coagulation experiment for P removal. The lower the coagulant basicity was, the higher phosphorus removal was achieved; and PACl0 showed the best performance. Dissolved and particulate phosphorus reduced gradually with the increase of the coagulant (PACl0). They were entirely turned into deposit phosphorus when the coagulant dosage was above 10 mg x L(-1). The demand of coagulant for turbidity control was proved to be unequal to that for phosphorus removal. The coagulant dosages of about 3-5 mg x L(-1) achieved the best turbidity removal in the experiment; while much higher dosage was needed to get desired phosphorus removal. The amount of AAP (algal available phosphorus) in the sediments changed according to coagulant (PAC10) dosages. AAP increased with the increase of coagulant dosage when the dosage was less than 5 mg x L(-1), then it decreased with further addition of coagulant above 5 mg x L(-1). It was proved that release of phosphorus in sediments would be controlled effectively by addition of coagulant overdosed compared to the need for turbidity removal, which is important to long-term control of phosphorus. It was indicated that the dosage of coagulant used for phosphorus removal can not use the sole criterion for turbidity removal; the need for total phosphorus removal, sediment release of available phosphorus (such as AAP) and other phosphorus control requirements should be considered; and a larger dosage would be needed.