ABSTRACT The present article compares the effectiveness of two chemical compounds to reduce the growth of biofilm adhering to the tubes of a heat exchanger-condenser refrigerated by seawater. The compounds tested in the study were: a quaternary ammonium compound (QAC) and an aliphatic amine (triethanol amina, TA). Each biocide was applied intermittently in a first shock stage and in a second stabilising stage. Prior to biocide dosing, a biofilm was created in the inner surface of the heat exchanger tubes under study (AISI 316L and 316Ti stainless steel). The evolution of the biofilm during growing and treatment phases was followed by indirect measurements, i.e. fluid frictional resistance (f) and heat transfer resistance (Rf ). The article also presents results of the impact of the different control strategies applied to the heat exchanger condenser efficiency. Both compounds removed the biofilm, and the tubes were practically restored to their clean condition. Ecotoxicology studies classified both biocides as environmentally harmless under the testing conditions.

中文翻译：

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季铵化合物和脂肪胺作为生物杀灭剂在减轻附着在由海水冷藏的热交换器冷凝器内表面的微污垢中的应用。对所应用的不同控制策略的效率的影响

摘要 本文比较了两种化合物在减少附着在由海水冷却的热交换器冷凝器管上的生物膜生长方面的有效性。研究中测试的化合物是：季铵化合物 (QAC) 和脂肪胺（三乙醇胺，TA）。在第一次冲击阶段和第二次稳定阶段中间歇地施加每种杀生物剂。在加入杀菌剂之前，在研究中的换热器管（AISI 316L 和 316Ti 不锈钢）的内表面形成生物膜。生物膜在生长和处理阶段的演变之后是间接测量，即流体摩擦阻力 (f) 和传热阻力 (Rf)。本文还介绍了应用于换热器冷凝器效率的不同控制策略的影响结果。两种化合物都去除了生物膜，管子实际上恢复到了清洁状态。生态毒理学研究将这两种杀生物剂在测试条件下归类为对环境无害。