Search

Your search keyword '"Yi, Tang"' showing total 4 results
Start Over Author "Yi, Tang" Topic sulfate-reducing bacteria
4 results on '"Yi, Tang"'

1. A method for controlling hydrogen sulfide in water by adding solid phase oxygen

Author

Yu-Jie Chang, Yi-Tang Chang, and Hsi-Jien Chen

Subjects
Environmental Engineering, Sulfide, Hydrogen sulfide, Population, Inorganic chemistry, Magnesium peroxide, Magnesium Compounds, chemistry.chemical_element, Bioengineering, Oxygen, Water Purification, chemistry.chemical_compound, Hydrogen Sulfide, Sulfate-reducing bacteria, Hydrogen peroxide, education, Waste Management and Disposal, Sodium sulfite, chemistry.chemical_classification, education.field_of_study, Renewable Energy, Sustainability and the Environment, Chemistry, Water, Hydrogen Peroxide, General Medicine, Peroxides
Abstract

This work evaluates the addition of solid phase oxygen, a magnesium peroxide (MgO(2)) formulation manufactured by Regenesis (oxygen-releasing compounds, ORC), to inhibit the production of hydrogen sulfide (H(2)S) in an SRB-enriched environment. The initial rate of release of oxygen by the ORC was determined over a short period by adding sodium sulfite (Na(2)SO(3)), which was a novel approach developed for this study. The ability of ORCs to control H(2)S by releasing oxygen was evaluated in a bench-scale column containing cultured sulfate reducing bacteria (SRB). After a series of batch tests, 0.4% ORC was found to be able to inhibit the formation of H(2)S for more than 40 days. In comparison, the concentration of H(2)S dropped from 20 mg S/L to 0.05 mg S/L immediately after 0.1% hydrogen peroxide (H(2)O(2)) was added, but began to recover just four days later. Thus, H(2)O(2) does not seem to be able to inhibit the production of sulfide for an extended period of time. By providing long-term inhibition of the SRB population, ORC provides a good alternative means of controlling the production of H(2)S in water.

Published
2007

2. The use of magnesium peroxide for the inhibition of sulfate-reducing bacteria under anoxic conditions

Author

Yu-Jie Chang, Yi-Tang Chang, and Chun-Hsiung Hung

Subjects
chemistry.chemical_classification, Microbial Viability, Sulfide, Sulfur-Reducing Bacteria, Magnesium, Sulfates, Hydrogen sulfide, Inorganic chemistry, Heterotroph, Magnesium peroxide, chemistry.chemical_element, Magnesium Compounds, Bioengineering, Sulfides, Applied Microbiology and Biotechnology, Anoxic waters, Peroxides, Oxygen, chemistry.chemical_compound, chemistry, Environmental chemistry, Sulfate, Sulfate-reducing bacteria, Biotechnology
Abstract

Sulfate-reducing bacteria (SRB), which cause microbiologically influenced material corrosion under anoxic conditions, form one of the major groups of microorganisms responsible for the generation of hydrogen sulfide. In this study, which is aimed at reducing the presence of SRB, a novel alternative approach involving the addition of magnesium peroxide (MgO2) compounds involving the use of reagent-grade MgO2 and a commercial product (ORC) was evaluated as a means of inhibiting SRB in laboratory batch columns. Different concentrations of MgO2 were added in the columns when black sulfide sediment had appeared in the columns. The experimental results showed that MgO2 is able to inhibit biogenic sulfide. The number of SRB, the sulfide concentration and the sulfate reducing rate (SRR) were decreased. ORCtrade mark as an additive was able to decrease more effectively the concentration of sulfide in water and the SRB-control effect was maintained over a longer time period when ORCtrade mark was used. The level of oxidation-reduction potential (ORP), which has a linear relationship to the sulfide/sulfate ratio, is a good indicator of SRB activity. As determined by fluorescence in-situ hybridization (FISH), most SRB growth was inhibited under increasing amounts of added MgO2. The concentration of sulfide reflected the abundance of the SRB. Utilization of organic matter greater than the theoretical SRB utilization rate indicated that facultative heterotrophs became dominant after MgO2 was added. The results of this study could supply the useful information for further study on evaluating the solution to biocorrosion problems in practical situations.

Published
2008

3. Microbial community analysis of anaerobic bio-corrosion in different ORP profiles.

Author

Chang, Yu-Jie, Chang, Yi-Tang, Hung, Chun-Hsiung, Lee, Jyh-Wei, Liao, Hua-Mao, and Chou, Hsi-Ling

Subjects
*BIOTIC communities, *ANAEROBIC bacteria, *BIODEGRADATION, *OXIDATION-reduction reaction, *SULFATE-reducing bacteria, *MICROORGANISMS
Abstract

The effect of ORP (oxidation–reduction potential) on the bacterial community and corrosion rate was investigated in this study. A continuous sulfate-reducing bacteria (SRB)-enriched reactor equipped with an ORP controller was operated from anaerobic to anoxic condition in this bio-corrosion experiment for over 200 days. Testing mild steel coupons were placed into the reactor for immersion test which was used to compare with the result of electrochemical corrosion current density. The results showed that as the ORP increased, the sulfide, corrosion current density and the proportion of SRB in microbial community would decrease. This study employed oxygen to change the microbial communities, which successfully enabled heterotrophs to inhibit SRB even under excessive TOC and sulfate inflow conditions. However, from the results of corrosion weight loss it could be discovered that the fact of higher control of ORP leading to better corrosion inhibition was not certain. Once the ORP was controlled to −250 mV, the same result could be achieved as well as the ORP being controlled to −180 mV. In addition to the advantage of energy-saving, controlling ORP at −250 mV can also prevent more corrosion reactions from possibly being caused by other microorganisms in the continuous rising of ORP. [ABSTRACT FROM AUTHOR]

Published
2014
Full Text
View/download PDF

4. A study of microbial population dynamics associated with corrosion rates influenced by corrosion control materials.

Author

Chang, Yu-Jie, Hung, Chun-Hsiung, Lee, Jyh-Wei, Chang, Yi-Tang, Lin, Fen-Yu, and Chuang, Chun-Jie

Subjects
*MICROORGANISM populations, *CORROSION & anti-corrosives, *SULFATE-reducing bacteria, *LACTATES, *BIODEGRADATION, *POLYMERASE chain reaction
Abstract

This research aims to analyze the variations of microbial community structure under anaerobic corrosive conditions, using molecular fingerprinting method. The effect of adding various materials to the environment on the corrosion mechanism has been discussed. In the initial experiment, sulfate-reducing bacteria (SRB) were inoculated in a series of batch culture flasks containing sterile growth media. Several testing coupons of mild steel were placed into the SRB-enriched columns, which contained excess sulfate and lactate. After incubating for 20 days, three materials (MgO 2 , H 2 O 2 and NaOCl) were added into the flasks so as to observe the effects on biocorrosion rate. Microorganism composition change was observed from the diversity profile using the PCR–DGGE (polymerase chain reaction – denaturing gradient gel electrophoresis) method. The results showed that hydrogen peroxide (H 2 O 2 ) prompted the microbial community to change quickly and easily and enhanced the corrosion rates of coupons (3–6 times faster than the control run). This fact suggested that adding H 2 O 2 could inhibit biological activities initially; however, it ultimately caused more serious corrosion due to breaking down the protective layer, composed of mainly FeS. When MgO 2 was added into the SRB-enriched culture, the corrosion rate on the mild steel test coupons was inhibited to one third of that in the control column. The DGGE profile analysis shows that SRBs were clearly inhibited for a long time (more than 100 days) after adding MgO 2 . The durability of the MgO 2 reaction could be demonstrated by DGGE variations as well as water quality monitoring results. [ABSTRACT FROM AUTHOR]

Published
2015
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results