Why use clean steam

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Why use clean steam? In industrial production processes, certain applications such as food and beverage processing, aseptic filling, direct UHT treatment of dairy products and milk powder, cooking raw materials for liquor production and filling of draft beer, humidification in hospital operating rooms and sterilization in supply centers, as well as the cleaning and disinfection of cosmetic containers, require the use of steam that meets specific standards. Common issues include contamination by steam with yellowish water, various impurities in the steam, pressure fluctuations, as well as potential factors that are not easily detectable, such as air present in the steam, superheated steam, and moist steam. When these potential steam contaminants come into contact with the product or its container, there is a risk of contamination. Industrial steam is the steam produced by directly heating furnace water with ordinary steam boilers. Industrial steam is used as a heat carrier, generally for indirect heating or direct contact heating where such contact is not required. Ordinary industrial steam meets most direct or indirect heating requirements; compared to other heating media or fluids, steam is the cleanest, safest, sterilest, and most efficient heat transfer medium. During transportation, steam can cause corrosion of carbon steel pipes due to condensation; if these corrosive substances make their way into the production process, they may affect the final product. When the steam contains more than 3% condensate water, although its temperature meets the required standards, the presence of this condensate on the surface of the product hinders heat transfer. As a result, the steam temperature decreases gradually as it passes through the layer of condensate water, causing the actual contact temperature with the product to be lower than the specified design temperature. In particular, the boiler water carried by the boiler may contaminate products that come into direct contact with steam. Therefore, using a Watt high-efficiency steam-water separator at the steam inlet is usually very effective. The presence of non-condensable gases such as air has an additional effect on the temperature of steam. If air remains in or is not completely removed from the steam system, it acts as a poor conductor of heat; as a result, cold spots are formed, preventing the products in contact with this air from reaching the desired temperature. Steam superheat is an important factor affecting steam sterilization, yet it is often overlooked. The principle of saturated steam sterilization is that when steam comes into contact with cold products, it condenses and releases a large amount of latent heat, thereby raising the temperature of the products. Overheated steam, with properties similar to dry air, has low heat transfer efficiency on its own ； The experience of Watt Energy Saving’s steam engineers shows that when superheated steam releases sensible heat and its temperature drops without reaching the saturation point, condensation does not occur; at this stage, the amount of heat released is very small, resulting in heat transfer that is insufficient to meet sterilization requirements. This phenomenon becomes apparent when the overheating exceeds 3°C. Steam superheating can also cause items to age rapidly. The superheat of clean steam is often caused by the depressurization of that steam; a smaller pressure reduction ratio along with accurate temperature monitoring can effectively control the superheat of clean steam. The quality of the feedwater in the steam boiler affects the cleanliness of the steam. We also know that as the steam in the boiler evaporates, it inevitably carries some of the boiler water into the steam system, and this dirty boiler water in the steam system causes certain damage and negative effects on it. Through condensate purity testing, the purity, salt content (TDS), and pathogen detection of ordinary industrial steam condensate are the basic parameters for clean steam. In accordance with the regulations set by the U.S. FDA, typical water treatment chemicals such as sodium hexametaphosphate, which is used to prevent scale formation in steam boilers, sodium hydroxide for corrosion inhibition, and sodium metabisulfite for deoxygenation, cannot be used in steam boilers that come into direct contact with food ingredients or foods. In cases where steam is used for water treatment in food and beverage processing or medical sterilization, the large amounts of additives present in the boiler water can end up spraying directly onto the food ingredients or foods, posing risks to food safety. Therefore, Watt Energy Saving’s standards for clean steam require at least water supply purity, the dryness of the steam itself (i.e., the amount of condensate), the level of non-condensable gases, an appropriate superheat, suitable steam pressure and temperature, as well as a sufficient flow rate. In particular, the flow rate of clean steam matters; fluctuations in this flow rate directly cause changes in the pressure and temperature of the clean steam. Meanwhile, changes in the flow rate of clean steam also have a significant impact on the dryness of the steam. The cleanliness assurance of clean steam depends not only on its generation, but also on the design of its clean delivery pipeline system, as well as the control of the clean steam heating system and the drainage scheme for condensate water. Only by relying on the actual manufacturing processes and requirements can the appropriate grade of steam be selected. The quality of the clean steam generated by heating with RO water is closely related to technical factors such as the quality of the water supplied to the clean steam generator, the design of its internal cleaning systems, the choice of materials used, the control methods employed, and the relevant verification requirements. Both pure steam generators and clean steam generators can produce steam of different levels of purity, while the Watt ultra-pure filtration system is proven to be the most economical and reliable source of clean steam. In the context of food safety, ultra-pure steam filtration systems will be increasingly used on a wide scale.