General Information: POLYBROM is a unique product that greatly aids the application of chlorine or bleach in agricultural applications. It's well known that chlorine products lose most of their effectiveness in the presence of nitrogen forms of chemicals. This presents a problem with the amount of fertilizers used in our industry. This synergism between the POLYBROM and chlorine gas or bleach
eliminates the problem and provides a powerful tool to control bio-growths in your
system. It is well recognized that chlorine is the only biocide allowed in most
states for safe control of these bio-growths. VIABLE ALTERNATIVE TO GAS CHLORINATION Why look for an alternative to chlorine? Is it not an excellent biocide for microorganisms? It must be safe to use, because we use it in our drinking water. Let's take a look at the advantages and disadvantages of chlorine. 1.) Advantages: It's relatively inexpensive. 2.) Disadvantages: Chlorine demand of the water, pH range of activity, penetration of bio-mass, nitrogenous material in the system, the safety programs required, safety of workers (chlorine gas can kill people) and the environmental impact. Bromine used in agriculture offers advantages over other compounds. 1.) Control of algae and other microorganisms without the risk of phytotoxicity associated with other algicides or biocides. 2.) Almost all agricultural systems are in a nitrogen environment, making use of chlorine marginal in activity and also for the environment. 3.) Bromine chemistry has the advantage of using the active hypobromous acid or bromoamines, both are very active oxidizing agents and broad spectrum biocides, active against all forms of microorganisms, including algae, fungi, viruses, and protozoa. But most important is its ability to loosen and dissolve attached biomass. Let's examine some variable of systems treated with bromine chemistry. Microorganisms cannot develop immunities or even resistance to activated bromine, as with other biocides including chlorine. When bromine is fed along with chlorine source into the system water, it is activated and becomes a powerful oxidizing biocide, not a metabolic poison like the quaternary ammonium salt compounds. The bromine chlorine combination is many times more active than chlorine by itself and does not develop the resistance that the chlorine does to microorganisms. Iron reducing bacteria and sulfate reducing bacteria often require dosages of 100 to 200 ppm over a 96 hour control test to establish a "kill" as compared with bromine/chlorine as established by the Wharf Institute in Madison, Wisconsin. NITROGEN ENVIRONMENT When chlorine is introduced into a system where there is nitrogenous material present (even at levels of 0.25 to 1 ppm), instead of developing the active biocides of hypochlorous acid or even the inactive chlorite ion, you will develop a monochloramine. White's handbook of chlorination classifies chloramines as being only 1/100th to 1/150th as active a disinfectant as the parent compound of the HOCL (hypochlorous acid). By contrast with this, bromine also converts, but to a dibromamine in this environment, however, dibromamines are as active and even more effective disinfectant than the HOCL and retains most of the biocidal activity of the parent compound. If we look at the relative decay ratios of bromamines vs. chloramine, it will help explain the importance of bromine chemistry in agricultural situations and the positive impact it has on the environment. Bromamines decay to very low levels in less than an hour, while chloramines require very long periods to decay to the same levels. We often talk about chlorine demand or breakpoint chlorination. Let's examine this reaction. When chlorine is added in sufficient excess, the ammonia and nitrogenous compounds are completely oxidized to nitrogen gas. This is known as "breakpoint" chlorination, which is frequently used to remove the chloramines and replace them with the more active hypochlorous acid. For bromine chemistry this is unnecessary because of the biocidal activity of bromamines. Ammonia and nitrogen compounds are always present in an agricultural environment and most often in an excessive amount. However, ammonia at 0.1 ppm is nearly twice the amount needed to convert 0.25 ppm of chlorine to chloramine and substantially reduces the rate of kill. |
