BCDMH

Abstract: Biofouling in recirculating water systems may be controlled by admixing or otherwise providing 1-bromo-3-chloro-5, 5-dimethylhydantoin ("BCDMH") to the water at a level effective to control biological film-forming organisms and thereafter maintaining the BCDMH concentration at a level sufficient substantially to inhibit regrowth of such organisms.

Abstract: A biocide (l‐bromo‐3‐chloro‐5,5‐dimethylhydantoin), was tested for efficacy against planktonic and biofilm bacteria in a laboratory model to simulate a water system. BCDMH was continually added to the continuous culture chemostat which was operated using an artificially softened water to simulate conditions within a cooling tower. Biofilm developed on stainless steel and mild steel tiles suspended in the culture. The consortium of bacteria growing in the chemostat model included legionellae, pseudomonads, methylobacteria and actinomycetes. Flavobacterium, Alcaligenes and Achromobacter spp. which were grouped together as Gram negative (GN) bacteria were also present. At biocide concentrations of 1 or 2 mg.l‐1 bacteria in the planktonic phase were dramatically reduced in the culture whereas only a 1 log drop in viable bacteria was detected in the biofilm. When the concentration of BCDMH was increased to 4 or 6 m.gl‐1 a 3 log reduction was observed in the number of viable bacteria recovered from the biofilm....