Why clean steam should be used

Why should we use clean steam? In the industrial production process, some applications such as food and beverage technology, aseptic filling, UHT of dairy products and milk powder directly, cooking of liquor raw materials and filling of draft beer, humidification of hospital operating room and sterilization of supply center, cleaning of cosmetics containers and steam for disinfection are required Common requirements include steam yellow water pollution, various impurities in steam, pressure fluctuation and other phenomena, as well as potential influencing factors that are not easy to find such as air, superheated steam and steam humidity in steam When these potential steam contaminants come into contact with products or product containers, there is potential contamination Industrial steam is the steam produced by ordinary steam boiler directly heating boiler water Industrial steam as a heat carrier is generally used for indirect heating or direct contact heating without requirements General industrial steam basically meets most of the requirements of direct or indirect heating Compared with other heating media or fluids, steam is a clean, safe, sterile and hot medium During the transportation of steam, the carbon steel pipe will be corroded due to condensation If the corrosive substance is carried into the production process, it may affect the product When the steam contains more than 3% condensed water, although the temperature of the steam is up to the standard, due to the hindrance of the condensed water distributed on the product surface to the heat transfer, the steam temperature will gradually decrease when passing through the condensate film, so that the actual contact temperature to the product will be lower than the design temperature requirements In particular, the water quality of the boiler water carried by the boiler may pollute the products in direct contact with the steam So it is very effective to use watt separator at steam inlet The existence of air and other non condensable gases will have an additional impact on the temperature of the steam The air in the steam system is not excluded or not completely excluded On the one hand, because the air is a bad conductor of heat, the existence of air will form a cold point, so that the product attached to the air can not reach the design temperature Steam superheat is an important factor affecting steam sterilization, which is often ignored The principle of saturated steam sterilization is that the steam condenses and releases a lot of latent heat energy, which makes the temperature of the product rise On the other hand, when the superheated steam releases sensible heat and the temperature drops below the saturation point, condensation will not occur At this time, the heat released is very small, so that the heat transmission can not meet the sterilization requirements This phenomenon is obvious when the temperature is over 3 ℃ Overheating of steam can also cause rapid aging of items The superheat of clean steam is often caused by the pressure reduction of clean steam A small pressure reduction ratio and temperature detection can effectively control the superheat of clean steam The feed water quality of steam boiler will affect the cleanliness of steam We also know that when the steam in the boiler evaporates, it will inevitably bring part of the boiler water into the steam system, and the dirty boiler water in the steam system will have certain damage and influence on the steam system Through the test of condensate purity, the purity, salt content (TDS) and pathogen detection of common industrial steam condensate are the basic parameters of clean steam At the same time, according to the FDA regulations, sodium hexametaphosphate is used as the scale inhibitor of steam boiler, and sodium hydroxide for corrosion inhibitor, Typical water treatment chemicals such as sodium pyrosulfite used for deaeration cannot be used in steam boilers which have direct contact with food materials or food For boiler water treatment which uses steam for food and beverage processing and medical sterilization, a large number of additives in the boiler water often spray directly on food materials or food products, causing food safety problems So clean steam at least includes purity of feed water, dryness of steam itself (condensate content), content of non condensable gas, superheat, proper steam pressure and temperature, and sufficient flow Especially the flow and flow fluctuation of clean steam directly lead to the change of pressure and temperature of clean steam, and the change of clean steam flow will also greatly affect the dryness of steam The cleanliness assurance of clean steam not only lies in the generation of clean steam, but also includes the design of clean transmission pipeline system, the control of clean steam heating system and the condensate discharge scheme Only according to the actual process and actual needs to select the appropriate level of steam, relying on RO water heating generated clean steam, its quality has a close relationship with the quality of clean steam generator water supply and internal clean process design, relevant material selection, control mode and technical considerations of relevant verification requirements Pure steam generator and clean steam generator can provide different levels of clean steam, and super clean filter device is the verified economic and stable source of clean steam Super clean steam filter device will be more and more widely used in the environment of food safety