Challenges and solutions for biofiltration of hydrophobic volatile organic compounds.

Simultaneous Removal of Multicomponent VOCs in Biofilters

Biological methods for odor treatment – A review

Recent progress and perspectives in biotrickling filters for VOCs and odorous gases treatment.

Elimination of mass transfer and kinetic limited organic pollutants in biofilters: A review

BACKGROUND: The performance of two biotrickling filters (BTFs) was evaluated for styrene removal from gas streams at the start-up period and at a pseudo-steady-state under various operating conditions. RESULTS: The BTFs exceeded 99% removal efficiency within 19 days when the average inlet styrene concentration was 250 mg m −3 and gas empty bed retention time (EBCT) was 30.0 s. The effect of a surfactant, Triton X-100, on styrene removal was examined by comparative experiments in which one biofilter was fed with nutrient solution with the surfactant while the other without the surfactant, and the average organic loading rate of styrene was set at 65.3, 100.9 and 201.7 g styrene m −3 h −1 , respectively. Results showed that the corresponding average removal efficiency was 87%, 70% and 50% for the BTF withoutsurfactant,whiletheaverageremovalefficiencyfortheBTFwithsurfactantwas96%,92%and82%.Excessivebiomass accumulation was observed in the medium when the styrene loading rate was high. However, the biomass density within the BTF medium when the surfactant was added remained stable during the whole period of the operation. CONCLUSION: These results demonstrated that the use of Triton X-100 can improve the degradation of styrene and control the excessive biomass accumulation. c � 2012 Society of Chemical Industry

Effect of surfactant on styrene removal from waste gas streams in biotrickling filters

Modified zeolite as well as preparation method and application thereof

The invention discloses a method for preparing ammonium chloride by a recovered modified zeolite. In the method, a counter-current regeneration tower technology is adopted; counter-current washing is performed on the recovered modified zeolite through hydrochloric acid; then absorbed ammonia nitrogen is recovered in an ammonium chloride concentrate form; finally the ammonium chloride concentrate is directly evaporated to obtain a solid ammonium chloride fertilizer; after the above steps, the regenerated modified zeolite is put into the pre-treatment process of breeding waste water again as an adsorbent in order to recycle the ammonia adsorption, wherein the recovered modified zeolite refers to the saturated modified zeolite after adsorbing the ammonia nitrogen, and the modified zeolite is prepared by mixing natural zeolite with magnesium oxide, then roasting and cooling. The method disclosed by the invention has the advantages of fully utilized resources, energy saving and environmental protection, low technology cost, high product additional value and the like.

Tiantian Song

Papers

Effect of surfactant on styrene removal from waste gas streams in biotrickling filters

Modified zeolite as well as preparation method and application thereof

Method for preparing ammonium chloride by recovered modified zeolite