Technical
salts are controlled to a maximum level of 225ppm by means of a formulated dispersant and antiscalants . It can be used with ethylene glycol in winterised systems , thereby eliminating the incompatibility problems of chromates .
MICRO BIOCIDES Meeting certain water quality standards requires testing for Legionella bacteria . SANS 893‐1 provides guidelines for the risk management of Legionella bacteria in any undertaking , while SANS 893‐2 focuses on requirements for designing and managing hot- and cold-water systems that could create and transmit water droplets ( and thus Legionella bacteria ).
Experience has shown us that cooling towers , evaporative condensers as well as hot- and cold-water systems in a wide variety of workplaces present a risk of exposure to Legionella bacteria . Corrosion , scaling , fouling and biofouling are all inter-related and if not treated correctly can lead to inefficient processes , higher water and energy usage and increased plant maintenance costs .
Different micro biocide products are available
• Broad-spectrum biocide for use in RO , UF and NF systems where bacteria and biofilm are expected to be present . It provides microorganism control ( including Legionella ) and clean systems . It can be used alone or with other biocides on a rotation basis .
• Broad-spectrum algaecide and biocide are especially effective for the control of algae and slime in industrial water systems , air evaporative condensers and air conditioning units .
• Broad-spectrum biocide for closed circuits .
• Low-cost algaecide and biocide when combined with other treatment products .
Businesses with cooling towers should also consider additional water filtration to remove suspended solids , organics , and silt particles in their cooling systems . Reducing fouling and biological growth in the cooling systems helps to control other issues in the system , such as scaling and corrosion . Side stream filtration is an effective tool for the control of deposition and fouling in a cooling water system . RACA
Allmech is a South African manufacturer of boilers and supplier of water treatment components .
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RACA Journal I July 2022 www . refrigerationandaircon . co . za