Corrosion inhibitor for cooling systems

Industrial n e w s

No uvelles de I'in dustrie Accumulator for overflow ammonia Liquid ammonia that escapes from evaporators can be collected and boiled off in ammonia accumulators. In certain systems the liquid tends to go from the evaporator into the suction line and then into the compressor. Vertical ammonia accumulators, manufactured by RECO, are designed to be installed in this main suction line. They are made from steel pipe or welded steel cylinders welded to elliptical steel heads. Each contains a coil of steel pipe which boils off accumulated liquid ammonia and a stainless steel mesh pad which acts as a mist eliminator. Ten sizes of accumulator are available, with diameters from 3Q.48 cm to 1 52.4 cm.

Vertical ammonia accumulator

Volume 2 Number 3 May 1979

Connections are welded on for the suction inlet and outlet, the hot liquid inlet, the liquid outlet, the safety relief valve, the oil drain and the high level alarm float switch. The manufacturers recommend the accumulators for use in ammonia systems that use multiple flooded evaporators, in icemakers, in scraped surface heat exchangers and in tube chillers without surge drums. They say that the accumulators musp be chosen for the lowest suction pressure that will apply with the compressors at full load.

George C. Briley, Refrigeration Engineering Corp., PO Box 3-C, San Antonio, Texas 78217, USA

Corrosion inhibitor for cooling systems Corrosion inhibition without pollution is offered byZimmite. Their inhibitor for use in industrial cooling water systems, ZC362, is a mixture of biodegradable organic compounds and n0n-polluting inorganic compounds, instead of the commonly used chromates, phosphates and zinc. Neither does it contain polyphosphate which, they say, leads to the formation of calcium phosphate sludge at all pH levels. The inhibitor works by forming a protective film on the metal surface, and it also contains a mud remover and a scale i nhi bitor to prevent deposits from hard water. It is designed for use at a range of pH values and the manufacturers advise against an acid feed. They claim that it is stable with respect to chlorine and at high temperatures and that it eliminates the need for supplementary deposit controls.

Zimmite (UK) Ltd, 34 Westminster Palace Gardens, London SWl P 1RL, UK

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Housing for condensing umt(top) and the semi-hermetic air-cooled unit (bottom)

Ready housed Housed condensing units were introduced by Hubbard in January 1979. These are semihermetic air-cooled units and there are six models ranging from 745.7Wto2237.1W(1 hpto3 hp).They are manufactured by Frigidaire and most of the major components are interchangeable with the Frigidaire FAH series. Refrigerants 12, 22 and 502 can be used with the units. The housing was designed with the aim of reducing noise and vibration. It is made from folded steel, welded into a rigid framework. On three sides t h e r e are removable, Iouvred panels which are fitted with captive fasteners. They are intended to give low air resistance so that the throughput of air to cool the condenser and evaporator is maximized. The air cooled condenser is on the fourth side. The manufacturers say that their housed units are cheaper to buy than separate units and housing, and that they are more compact and cheaper to install.

Hubbard Commercial Products Ltd, Frigidaire Refrigeration, 4 Perivale Industrial Estate, Horsenden Lane South, Greenford, Middlesex UB6 7NY, UK 177