Slime control

Continuous chlorination of a cooling water system often seems most pmdent for microbial slime control. However, it is economically difficult to maintain a continuous free residual in some systems, especially those with process leaks. In some high demand systems it is often impossible to achieve a free residual, and a combined residual must be accepted. In addition, high chlorine feed rates, with or without high residuals, can increase system metal corrosion and tower wood decay. Supplementing with nonoxidizing antimicrobials is preferable to high chlorination rates. 

Sodium chlorite has also been used for treatment and removal of toxic and odorous gases such as hydrogen sulfide and mercaptans. Chlorine dioxide from chlorite is also useful for microbial and slime control in paper mills and alkaline paper machine systems (164,165). The use of sodium chlorite in textile bleaching and stripping is well known. Cotton is not degraded by sodium chlorite because the oxidation reactions are specific for the hemiceUulose and lignin components of the fibers. 

Donohue, J.M., A.J. Piluso, and J.R. Schreiber. 1966. Acrolein — a biocide for slime control in cooling water systems. Mater. Protect. 5 22-24. 

Adverse oxidation of membrane occurs at higher concentrations of oxidizers such as chlorine, ozone and hydrogen peroxide. The chemicals are important for slime control, and rather high concentrations of the chemicals are dosed for sterilization of RO feed system, especially in cases of ultrapure water system, and of waste water treatment system. The evaluation of membrane durability against oxidizing chemicals informs us the proper procedures for RO maintenance. 

C. Chlorophenols. Chlorophenols have been extensively used since the 1930 s as insecticides, fungicides, mould inhibitors, antiseptics and disinfectants. The annual production volume is estimated to be in the order of 150 000 tons. In the US penta-chlorophenol is the second heaviest in use of all pesticides (38). The most important use of 2,U,6-tri, 2,3,, 6-tetra- and pentachlorophenol (or their salts) is for wood protection. Penta-chlorophenol is also used as a fungicide for slime control in the manufacture of paper pulp and for a variety of other purposes such as in the tanning process of leather and an additive in cutting oils and fluids, paint, glues and out-door textiles. 

A Simulated Cooling Tower for Evaluating Slime Control... 

Hydroxypropyl methanethiosulfonate. Organo-sulfur group. Good bacterial slime controller for cooling systems with pH below 7.5. Limited value as algaecide or fungicide and at alkaline pH. Typical product is 11 to 12% active, with dose rate of 20 to 100 ppm based on volume. 

Tetrachloro-2,4,6-cyano-3-benzonitrile. Similar in action to the chloro-phenols. Good slime controller, especially algal slimes. Reasonable performance as a general bactericide. Effective within pH range 6.5 to... 

To prevent the problems caused by slime formation, various microbicides (slime-controlling agents) can be used. Of these, 5-chloro-2-methyl-4-isothiazo-line-3-one (Cl-MIT 1) is the most widely used as a slime-controlling agent, a bactericide, an algicide or a fungicide, for various industrial water systems such as those in cooling-water units or papermills, as it has an excellent microbicidal activity. [2]... 

Metasol [Merck], TM for a series of chemicals used as fungicides, mildewicides, bactericides, slime control agents for pulp- and paper-mill systems, and as preservatives for all types of systems. Type (J-26) is claimed to be a broad-spectrum antimicrobial agent with a minimum ecological hazard. 

Use Slime control agent for pulp and paper-mill systems. 

Flotation methods allow recovery of fibers from water, which are raised to the surface on bubbles as a thick mat, which forms on the top of an aeration cell. This mat, which is virtually free of grit, is recycled to the pulp working stream. Slime growth in the aeration cell is discouraged by strong alternation of conditions such as pH, temperature, or chlorination level. Organomercury slime control agents were once used for this purpose. 

Pentachlorophenol was chosen because it is a broad spectrum biocide widely used as a wood preservative and as a slime control agent.17-20 8-Hydroxyquinoline had been used as a fungicide before 1900 and is thought to function by chelating metal ions.21 23 Tribromosalicylanilide is an active biocide with low dermatological effects to humans.24-26 jj-g biocidal effects vary upon the addition of surfactants to its medium. o-... 

Ethyl lactate is used as a high-boiling solvent for cellulose ether [66]. Phenyl mercuric lactate is obtained by reacting phenyl mercuric acetate with lactic acid. It is used in slime control of paper stock [67]. 

Slime-Trol. [Betz Industrial] Slime control agoit... 

Alkazine . [Rhone-Poulenc Surf.] Imidazolines emulsifier, antistat, corrosion inhibitor, strftener fin textiles, plastics, asphalt, water repdUent treatment, cutting oils, slime control additive in paper processing, wetting and flocculating agent, lubricant pigment dispersant... 

Blancol . [Rhone-Poulenc Surf.] Sodium naphthalene-formaldehyde condensates thinning, dispersant, peptizing agent, dye-leveling agent us in p r industry for slime control, improved retention of fillers or fines, improved sizing. 

Acrolein is used as an antimicrobial agent to prevent the growth of microbes against plugging and corrosion, to control the aquatic weed and algae, in slime control in paper manufacturing, as a tissue fixative, and in leather tanning. 

Products and Uses An ingredient in germicides, deodorants, algicides, and slime control products. 

The best approach to slime control is to maximise the wire retention of biodegradable materials, notably starches. This particularly applies to size press starch returned with mill broke. Size press starch can be a source of considerable wet-end problems. Unless retained quickly, size press starch will build up in the circuit waters, contributing to various wet-end problems (deposition, chemical interference and so on), and finally, to waste water loads. 

Chem. Descrip. Bis (tributyltin) oxide CAS 56-35-9 EINECS/ELINCS 200-268-0 Uses Antimicrobial for paper mill slime control, industrial cooling water, sec. oil recovery, hospital use, textiles, plastics, urethane foam, paper preservation antifoulant for ship-bottom paints wood presenrative Properties Straw-colored clear Iiq. sol. in org. soivs. relatively insol. in water m.w. 596 sp.gr. 1.17 dens. 9.7 Ib/gal f.p. < -45 C b.p. 180 C (2 mm) flash pt. (TCC) > 100 C 96% assay, 38.8% tin Toxicology Extremely irritating to eyes and skin can cause eye damage prolonged/repeated skin contact can cause chemical bums Biotrend 500 [ISP]... 

Uses Dispersant for pigments in aq. media tor use in agric. chemicals, mastics, caulks, sealants, pigment slurries and disps., inks, syn. polymers, paper coating disps., paper mill slime control, pitch control, pulp digestion, and tall oil separation... 

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