L. Hably szerk.: Studia Botanica Hungarica 21. 1989 (Budapest, 1989)

Ács, Éva; Lakatos, Gyula: Preliminary algological study on biofouling in industrial water systems

S T U D I A XXI. BOTANICA HUNGARICA (Antea: Fragmenta Botanica) 1989 p. 5-12 Preliminary algological study on biofouling in industrial water systems by É. ÁCS and Gy. LAKATOS (Received October 10,1989) Abs t ract: This paper deals with the algological investigation and the elimination of biofouling in industrial cooling water systems. Samples were taken from cooling water systems of different Hungarian Works in 1982. The algal fouling of different sampling sites was compared by cluster analysis. We give an outline about the possibilities of protective measures. INTRODUCTION A frequent problem of industrial water management is the forming of biofouling on the heat exchange surface of open cooling water systems and the elimination of these deposits (BIRCHALL, 1979; MANSFIELD, 1978; THACKERY, 1980; etc.). The formation of biofouling involves the danger of increasing the corrosion, decreasing the cooling efficiency and excessing the energy demand. Biofouling developing on the heat exchange surface of cooling water systems can be divided into inorganic and organic fraction. The former one is mainly resulted due to the precipitation of ferric compounds and scale. The latter one consists of living and dead algae, fungi and slime-forming bacteria. The quickly and massively proliferating micro-organisms stop up the water distribution and aeration troughs and disrupt the flow of cooling water and a fouling crust of several centimeters on the cooling exchange surfaces. The higher temperature favours the proliferation which may cause difficulties in the system during the vegetation period when an intensive cooling would be necessary. The algae can continue their propagation in the winter months due to higher temperature of cooling water. Unfortunately, the fouling problems of water systems in Hungary is discussed by some papers only (LAKATOS et al., 1979; LAKATOS and PAPP, 1982; RÉCSEY, 1974). Among the papers published abroad it is worth mentioning those which focus on the biofouling composition of cooling water systems (BIRCHALL, 1979; MANSFIELD, 1978; SLADECKOVA, 1961), and THACKERY's paper (1980) which deals with this question from an economic point of view. Moreover, CHARACKLIS et al. (1982) and PEDERSEN (1982) present results on the dynamics of biofouling formation and the applicable methods for its study. KIRKPATRICK et al. (1980) present results of their investigations on the fouling formed on the surface of the cast- iron pipes.