Sulfide control

Medicine and Nutrition. A stabilized buffered suspension of selenium sulfide has been marketed for many years as Selsun Blue (Abbott Laboratories) for control of seborrheic dermatitis of the scalp. A similar sulfur or selenium sulfide shampoo containing a metallic cation complex has been prepared (122). Topical appHcation of selenium sulfide controls dermatitis, pmritis, and mange iu dogs (see Cosmetics Veterinarydrugs). 

Benoit JM, Gilmour CC, Mason RP, Heyes A (1999) Sulfide controls on mercury speciation and bioavailability to methylating bacteria in sediment pore waters. Environ Sci Technol 33 951-957... 

Pomeroy, R.D. and F.D. Bowlus (1946), Progress report on sulfide control research, J. Sewage Works, 18, 597-640. 

The three main types of sulfide control procedures give an overall subdivision, although some overlap between the three groups may exist. Some of these procedures may be relevant not just for the control of sulfide but also for the reduction of other odorous substances. An overview of the methods emphasizing the process aspects will be given. The descriptions of the methods will not aim at giving information on detailed design principles. 

Operational procedures for the control of sulfide problems have played an important role for existing sewer systems over the last 40-50 years. The reason is that sulfide problems have not always been considered and predicted in the design phase, or it has been acceptable to deal with sulfide problems in the daily operation of the sewer network. However, in pressure mains, sulfide formation may typically take place. In such systems, hydrogen sulfide control may be needed, and procedures that are operated by the municipality should be implemented. Table 6.4 outlines methods that may be used for such control. Some of these methods will be further considered. The details are described in the literature. Further information of relevance in this respect is found in Melbourne and Metropolitan Board of Works (1989), ASCE and WPCF (1982), ASCE (1989), USEPA (1974, 1985), Pomeroy et al. (1985) and Vincke et al. (2000). 

Chlorine the use of chlorine (Cl2) as a sulfide-controlling agent is based on its poisoning effect on the biological system and its oxidizing effect on sulfide. Chlorine is nonspecific, and a great number of side reactions with wastewater components may occur. Even concentrations of about 50 g m-3 have not efficiently been able to reduce sulfide concentrations of about 5-10 gS m-3. Chlorine is an environmentally problematic chemical that generally cannot be recommended for use in sewer systems. 

USEPA (1974), Process design manual for sulfide control in sanitary sewerage systems, USEPA 625/1-74-005, Technology Transfer, Washington, DC. 

Oxidation of H->S by Chlorine Chlorination is one of the most common methods of hydrogen sulfide control. The oxidation of dilute sulfide solutions by chlorine or hypochlorite involves a primary oxidation of sulfide to sulfur and a simultaneous secondary oxidation of a portion of the sulfur to sulfate. The overall reactions are as follows ... 

PRI-SC [Peroxide-Regenerated Iron-Sulfide Control] A process for removing hydrogen sulfide from sewage. Ferrous sulfide is added in the upper reaches of the system, precipitating iron sulfides and sulfur. Addition of hydrogen peroxide at two sites downstream recovers the iron as ferric hydroxide, which can be used in other water treatment. Developed by US Peroxide in Southern California in the early 2000s. 

Figure 8 Sulfate/Sulfide controls on mercury methylation in aquatic environments —the Gilmour curve. At relatively low sulfate concentrations (most freshwaters), methylation of mercury is limited hy the rate of sulfate reduction. At higher sulfate concentrations (saltwaters), sulfide buildup from relatively high rates of sulfate reduction results in decreased bioavailahility of mercury (figure from Danger et al. (2001) after Gilmour and Henry (1991).

Davis-Colley, R.J, Nelson, R.D. Williamson, K.J. (1985) Sulfide control of cadmium and copper concentrations in anaerobic estuarine sediments. Mar. Chem. 16,173-86. 

Pomeroy, R., and Bowlus, F. D. (1946). Progress Report on Sulfide Control Research. Sewage Works J. 18(4), 597-640. 

U.S. Environmental Protection Agency (1974). Center for Environmental Research Information, Cincinnati, OH. Process Design Manual for Sulfide Control in Sanitary Sewerage Collection Systems, NTIS No. PB-260479. 

Sulfide Control Method Mean Total Sulfide Content in Carbon Column Effluent, mg S/liler... 

The concentrations of Cu, Zn, Fig, Cd, and other metals in sediment pore water are controlled by the solubility of metal sulfides in the reduced zone where sulfate reduction and sulfide formation is dominant. Change in redox condition upon burial results in a system where the growth of diagenetic copper, zinc, and arsenic sulfides control the distribution and partitioning of metals and arsenic in the sediment. In polluted sediments, sulfate reduction plays a key role in the formation and retention of sedimentary S as metal sulfides. The majority of the iron and manganese in coastal lake sediments is associated with sulfidic forms, especially in saline area high in available sulfate that is reduced to sulfide. 

The titled sulfide controls coclcldiosls in animals and lice in chickens. It is also effective against scabies. Moreover, it is well known as a rubber vulcanization accelerator. 

Neubert N., Nagler T.F., Bottcher M.E. (2008) Sulfidity controls molybdenum isotope fractionation into euxinic sediments Evidence from the modem Black Sea. Geology 36, 775-778. 

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