Biocide treatment

Recommendations were made to begin treatment with corrosion inhibitors and to make system operation changes to reduce grease and oil fouling. Other water chemistry recommendations involved reducing the amount of aggressive anion in solution and pursuing biocidal treatment. 

From the orientation of the tubelike organisms it was clear that they were flourishing even though the system was periodically chlorinated (Fig. 6.25). Clearly, the biocidal treatment was inadequate. 

M. J. Franklin, D. E. Nivens, A. A. Vass, M. W. Mittelman, R. F. Jack, M. J. E. Dowling, and D. C. White. Effect of chlorine and chlorine/bromine biocide treatments on the number and activity of biofilm bacteria and on carbon steel corrosion. Corrosion, 47(2) 128-134, February 1991. 

Phull SS, Newman AP, Lorimer JP, Pollet B, Mason TJ (1997) The development and evaluation of ultrasound in the biocidal treatment of water. Ultrason Sonochem 4 157-164... 

Jenkinson DS, Powlson DS (1976) The effects of biocidal treatments on metabolism in soil. V. A method for measuring soil biomass. Soil Biol Biochem 8 209-213... 

The plant demonstration was scheduled to operate for a three month period, using one-half of the total capacity. One block (36 permeators) consisted of entirely new four-inch units ("Permasep" Model 0440-042), while a second block still had the permeators that had been installed two years earlier and which were operated during the period of performance decline. A single four-inch permeator was operated on a separate small stand without biocide treatment. This permeator served as a positive control for the biofouling capability of the RO feed water. 

The TBC measurements in Figure 3d are reported as logio values. The logio TBC of the RO feed water was 0.81 0.98 during the test, while the TBC observed in the reject stream of the new permeators was 2.45 0.74 and for the older permeators was 3.68 0.73. The control permeator had a meem TBC level of 4.94 0.75. These differences in the TBC between the RO feed water and reject streams effectively measured the biocide treatment, cuid reflected overall RO performance. 

Purpose. To determine an effective biocide treatment level to recover a contaminated aqueous system. 

Interpretation. The effective biocide treatment is the lowest concentration that produced sterility in the system within 7 days of biocide addition and inoculation. 

RjSnX RjSnX, RjSnXj, RSnXj RjSnXj, RSnXj Agricultural spraying, volatilization from biocidal treatments, antifouling paint sprays Incineration of organotin-treated or -stabilized waste materials. Glass coating operations to produce SnOj films... 

Some considerable risk may exist with cooling towers having no systematically documented routine preventive maintenance and biocide treatment program, or in systems in which there are biodeposits, slime, sludge, or turbidity, as evidenced by visual inspections. 

Biocides and pesticides in indoor air are connected with different damage to objects. However, for scientists and museum professionals it is difficult to distinguish damages related to biocide treatment from damages caused otherwise. 

For biocide treatment directly on the membranes, DBNPA is a good non-oxidizing biocide (see Chapter 8.2.5.2). For clean membranes, a dosage of about 100 ppm for 30 minutes 2 to 3 times per week is recommended. For heavier fouling, 100 ppm for 60 minutes 2 to 3 times per week should be fed. Alternatively, DBNPA can be fed continuously at about 2-3 ppm. Note that once biofouling gets out of control, it will be very difficult for DBNPA to work, because it is a non-oxidizer and cannot penetrate biofilm. DBNPA works best as a preventative treatment. 

Possible Biocidal Effect. There has been some interest in whether the morpholine process has an effect comparable with that of an ethylene oxide-type fumigation process. Brief tests by a Coming Museum microbiologist in 1973 indicated that the process does have a significant value as a biocidal treatment, but these findings would require much more testing before a firm conclusion could be reached. 

Some circulating water systems are maintained in a closed loop called a tempered water system. Since the water does not travel through a cooling tower, oxygen, which could cause corrosion, does not enter the system. Still, biocide treatment may be necessary since many corrosion-causing bacteria are anaerobic. —... 

The problem of bioactivity can be reduced or eliminated by the use of biocides. There are different types of biocides and one must be aware of the toxicity level of these to decide the most suitable biocide for that application. Already affected systems can be treated with biocides but it is very difficult to release the biofilm once it is formed. In that case a biocide treatment... 

PatentNumber US 5391370 A 19950221 GELLED PEG BIOCIDAL TREATMENTS Roe D C Polizzotti D M Betz Laboratories Inc. 

With some biocide treatments there is a simple direct relationship between ATP and viable cell counts. However, where the mechanism of biocide action is related to influences on cell bioenergetics, or the concentration range employed is biostatic and affects cell metabolism, then ATP results may not follow the same pattern as microbial counts. Under these circumstances low ATP results at relatively high microbial levels might be expected but it is also possible that ATP levels increase over a period of time. 

New EU directives may limit the development and application of new biocides and for this reason, and concerns on toxicity or pollution, there is interest in alternative water treatment techniques such as ultrasound, high-pressure vortexing and electro-coagulation. These may also be used where chemical treatment is not appropriate. ATP measurements are likely to prove useful to monitor the effectiveness of these types of treatment but as with chemical biocidal treatment the nature of the ATP results may depend on the mode of action. One type of electrochemical treatment has been evaluated in our laboratory. The results indicate that as with chemical biocide treatment the use of both Total and Free ATP measurements can be of value in the interpretation of the results, monitoring the process efficacy and in optimisation of this method of water treatment. 

Effect of Thermal and Chemical Biocide Treatments of Soil on Enhanced Microbial Activity... 

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