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HIGH EFFICIENCY DEAERATORS FEATURES ANDADVANTAGES
KAWAN® Deaerators effectively remove dissolved & corrosive gases like O2 & CO2 in boiler feed water. It designed based on positive pressure de-aeration principal. Make up water and low pressure condensate enter the multi trays pressure vessel through the properly size spay manifold. The mixture of make-up water and condensate is then cascaded downward on the de-aeration dome.
If a liquid at its saturation temperature, the solubility of a gas in is zero although the liquid must be strongly agitated or boiled to ensure is it completely deaerated. This is achieved in the head section of a deaeartor by breaking the water into as many small drops as possible and surrounding these drops with an atmosphere of steam. A high surface area to mass ratio and allow rapid heat transfer from the steam to the water, which quickly attains steam saturation temperature. The dissolved gasses released and carried with the excess steam to be vented to atmosphere. The deaerated water then falls to the storage section of the vessel. A blanket of steam is maintained above the stored water to ensure that gases are not reabsorbed.
KAWAN® Deaerators come in spray type and tray type, carbon steel or stainless steel, depending on customer's selection and application. Vessels are made to Malaysia DOSH or ASME U Stamp certification. Our deaerators have been applied in Malaysia, Indonesia, Vietnam, Saudi Arabia etc. and collaborated in industry like hotel, palm oil, distillation, petrol chemical, oleo-chemical etc.
WHY GASES NEED TO BE REMOVED FROM BOILER FEEDWATER?
Oxygen is the main cause of corrosion in hot well tanks, feed lines, feed pumps and boilers. If carbon dioxide is also present then the pH will be low, the water will tend to be acidic, and the rate of corrosion will be increased. Typically the corrosion is of the pitting type where, although the metal loss may not be great, deep penetration and perforation can occur in a short period. Elimination of the dissolved oxygen may be achieved by chemical or physical methods, but more usually by a combination of both. The essential requirements to reduce corrosion are to maintain the feed water at a pH of not less than 8.5 to 9, the lowest level at which carbon dioxide is absent, and to remove all traces of oxygen. The return of condensate from the plant will have a significant impact on boiler feed water treatment- condensate is hot and already chemically treated, consequently as more condensate is returned, less feed water treatment is required.
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