Elimination of high concentration hydrogen sulfide and biogas purification by chemical-biological process.

A chemical-biological process was performed to remove a high concentration of H2S in biogas. The high iron concentration tolerance (20gL(-1)) of Acidithiobacillus ferrooxidans CP9 provided sufficient ferric iron level for stable and efficient H2S elimination. A laboratory-scale apparatus was setup for a 45 d operation to analyze the optimal conditions.

Large-scale modular biofiltration system for effective odor removal in a composting facility.

Several different foul odors such as nitrogen-containing groups, sulfur-containing groups, and short-chain fatty-acids commonly emitted from composting facilities. In this study, an experimental laboratory-scale bioreactor was scaled up to build a large-scale modular biofiltration system that can process 34 m(3)min(-1)waste gases. This modular reactor system was proven effective in eliminating odors, with a 97% removal efficiency for 96 ppm ammonia, a 98% removal efficiency for 220 ppm amines, and a 100% removal efficiency of other odorous substances.

Harvesting biohydrogen from cellobiose from sulfide or nitrite-containing wastewaters using Clostridium sp. R1.

Harvesting biohydrogen from inhibiting wastewaters is of practical interest since the toxicity of compounds in a wastewater stream commonly prevents the bioenergy content being recovered. The isolated Clostridium sp. R1 is utilized to degrade cellobiose in sulfide or nitrite-containing medium for biohydrogen production.

Rapid acclimation of methanogenic granular sludge into denitrifying sulfide removal granules.

Rapid formation of denitrifying sulfide removal granules is of practical interest to start up an expanded granular sludge bed reactor for wastewater treatment. This study demonstrates that methanogenic granules can be easily acclimated into DSR granules in one day, removing all 1.30 kg m(-3) d(-1) sulfide and converting >90% of 0.

Degradation of cresols by phenol-acclimated aerobic granules.

High-strength cresol isomers were treated with phenol-acclimated granules in batch experiments. The aerobic granules effectively metabolized cresol isomers at concentrations up to 1,500 mg l(-1). The modified Haldane kinetic model, used to assess the kinetic behavior during cresol degradation by granule cells, yielded a high maximum specific growth rate (1.

Functional consortia for cresol-degrading activated sludges: toxicity-to-extinction approach.

The conventional roll tube and plating techniques are typically time consuming and can culture in vitro only a small fraction of microbes in natural microflora. This study utilizes a novel, simple, and rapid method, the toxicity-to-extinction approach, to obtain the minimal functional consortium that can effectively degrade meta- (m-), para- (p-), and ortho- (o-) cresols. The original sludge had 16 major bands by denaturing gradient gel electrophoresis (DGGE).

Degrading high-strength phenol using aerobic granular sludge.

Aerobic granules were adopted to degrade high-strength phenol wastewater in batch experiments. The acclimated granules effectively degraded phenol at a concentration of up to 5,000 mg l(-1) without severe inhibitory effects. The biodegradation of phenol by activated sludge was inhibited at phenol concentrations >3,000 mg l(-1).

Biodegradation of phenol using Corynebacterium sp. DJ1 aerobic granules.

The single-culture Corynebacterium sp. DJ1 aerobic granules were cultivated and were utilized to degrade high-strength phenolic wastewater. These granules can degrade phenol at sufficient high rate without severe inhibitory effects up to phenol concentration of 2000 mg l(-1).

Biofiltration of trimethylamine, dimethylamine, and methylamine by immobilized Paracoccus sp. CP2 and Arthrobacter sp. CP1.

A biofilter using granular activated carbon with immobilized Paracoccus sp. CP2 was applied to the elimination of 10-250 ppm of trimethylamine (TMA), dimethylamine (DMA), and methylamine (MA). The results indicated that the system effectively treated MA (>93%), DMA (>90%), and TMA (>85%) under high loading conditions, and the maximum degradation rates were 1.

Microbial populations analysis and field application of biofilter for the removal of volatile-sulfur compounds from swine wastewater treatment system.

A biofilter packed with granular activated carbon (GAC) was applied to eliminate volatile-sulfur compounds (VSC) emitted from solid-liquid separation tank in swine wastewater treatment system. Hydrogen sulfide, methanethiol, dimethyl disulfide, and dimethyl sulfide were effectively reduced to 96-100% at gas residence times of 13-30s. Elemental sulfur and sulfate are their primary oxidation metabolites.

Continuous deodorization and bacterial community analysis of a biofilter treating nitrogen-containing gases from swine waste storage pits.

A biofilter inoculated with Arthrobacter sp. was applied to the simultaneous elimination of trimethylamine (TMA) and ammonia (NH3) from the exhaust air of swine waste storage pits. The results showed that the biofilter achieved average removal efficiencies of 96.

Two-stage biofilter for effective NH3 removal from waste gases containing high concentrations of H2S.

A high H2S concentration inhibits nitrification when H2S and NH3 are simultaneously treated in a single biofilter. To improve NH3 removal from waste gases containing concentrated H2S, a two-stage biofilter was designed to solve the problem. In this study, the first biofilter, inoculated with Thiobacillus thioparus, was intended mainly to remove H2S and to reduce the effect of H2S concentration on nitrification in the second biofilter, and the second biofilter, inoculated with Nitrosomonas europaea, was to remove NH3.

Hydrogen sulfide gas treatment by a chemical-biological process: chemical absorption and biological oxidation steps.

In order to remove high concentrations of hydrogen sulfide (H2S) gas from anaerobic wastewater treatments in livestock farming, a novel process was evaluated for H2S gas abatement involving the combination of chemical absorption and biological oxidation processes. In this study, the extensive experiments evaluating the removal efficiency, capacity, and removal characteristics of H2S gas by the chemical absorption reactor were conducted in a continuous operation. In addition, the effects of initial Fe2+ concentrations, pH, and glucose concentrations on Fe2+ oxidation by Thiobacillus ferrooxidans CP9 were also examined.