Requirements for pure water in the food industry and related equipment processes

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Requirements for water quality in the food and beverage industry: Water used in this industry usually requires pretreated purified or distilled water, with a conductivity of less than 10 us/cm. It meets the sanitary standards for drinking water GB5749-2006, the standards for drinking purified water CJ94-1999, and the sanitary standards for bottled (barreled) drinking pure water GB 17324-2003. 　　The food and beverage industry is considered the conscience of a nation. With the increasing global pollution and people’s growing emphasis on health, stricter requirements are being placed on this industry as well. Ordinary municipal tap water or water from deep underground wells can hardly meet people’s needs. **Currently, management in the food and beverage industry has also gradually developed into a system of comprehensive oversight covering company establishment, the production process, and finished product inspection. Currently, a food hygiene and safety licensing system (QS certification) is implemented in the many food industries and all beverage sectors, requiring that both process water and finished product water be purified water, usually water purified by pure water treatment equipment. 　　Pure water is defined as drinking water that is free of viruses and bacteria, contains no suspended particles or soluble salts, and has had all kinds of organic and inorganic chemical contaminants removed. It is characterized by its purity and clarity, sweet and mellow taste, compliance with health standards, and being water that can be consumed without being boiled. Today, purified water is widely used by us for domestic use, industrial production, medical and health purposes, in the food, beverage, and wine industries, for agricultural production, in electroplating and coating processes, as well as in the electronics, power, textile, and paper manufacturing sectors, among others. An important criterion for measuring pure water is conductivity (i.e., the water’s ability to conduct electricity). The more impurity ions are present in water, the higher its conductivity (the H+ and OH- ions produced by the ionization of water itself can also enable water to conduct electricity). Distilled water, as we often refer to it, is pure water produced by distillation. Drinking pure water refers to water that is suitable for direct consumption; it is produced by using water that meets the sanitary standards for drinking water as the raw material, and by applying methods such as distillation, deionization, ion exchange, reverse osmosis, and other appropriate processing techniques to remove minerals, organic substances, harmful impurities, and microorganisms from the water. Such water contains no additives whatsoever (with the exception of ozone). 　　The water quality produced by food and beverage reverse osmosis pure water equipment meets the requirements of GB17324-2003 for hygiene standards of bottled (barreled) drinking pure water; it complies with GB5749-2006 for hygiene standards of domestic drinking water; it adheres to CJ94-1999 standards for drinking water; it meets GB/T19249-2003 standards for reverse osmosis water treatment equipment; and it satisfies the latest standards for the food, beverage, and alcohol industries.

Application scope of food and beverage reverse osmosis pure water equipment: It is suitable for producing pure water used in various fruit juice and tea beverage production processes, as well as pure water for beer brewing. It can also be used in dairy processing, vegetable processing, and milk production. This equipment is applicable for various food production processes, as well as for producing pure water used in liquor blending and beer production. It is also used for producing bottled pure water and mineral water, as well as for providing direct drinking water in hotels, residential complexes, and office buildings. 　　Features of food and beverage reverse osmosis pure water equipment:
1. Key components: Water pump – Southern Water Pump brand; RO reverse osmosis membrane – imported from the United States.
2. Online water quality monitoring function, allowing constant tracking of the quality of the water produced.
3. Fully automated control via programmable controller, with an user-friendly operation display system; the equipment can be operated with just one button. It also features protection against water supply interruptions and shuts down when the tank is full.
4. Automatic flushing upon startup to avoid the need for manual cleaning, thereby extending the lifespan of the RO reverse osmosis membrane.
5. Elegant and attractive design, with safety insulation properties that meet GLP safety standards.
6. Real-time display of flushing, water production, full tank, low water level, and maintenance status; it also includes audio and visual alarm functions.
7. Modular and quick-connect design for easy installation and maintenance; it occupies less space, making maintenance simpler.
8. The RO membrane equipment has a scheduled automatic flushing program upon startup, along with functions such as self-checking upon startup, low water level alarms, automatic reset in case of power outages, and protection against low and high pressures. 　　9. Direct connection to tap water; 10. Comprehensive after-sales service, with a 1-year free warranty (excluding consumables). Requirements for the water supply used in food and beverage reverse osmosis water purification systems: For city tap water with a conductivity of 800 us/cm, it is recommended to use a water softening device. Process design for food and beverage reverse osmosis water purification systems: 1. A single-stage reverse osmosis process is used to produce water suitable for food and beverage production. The process is as follows: Raw water tank → Pressure pump → Multi-media filter → Activated carbon filter → Safety filter → High-pressure pump → First-stage reverse osmosis → Pure water tank. 2. A two-stage reverse osmosis process is used to produce pure water. The process is as follows: Raw water tank → Pressure pump → Multi-media filter → Activated carbon filter → Safety filter → High-pressure pump → First-stage reverse osmosis → High-pressure pump → Second-stage reverse osmosis → Pure water tank → Ozone sterilization → Finished product tank → Pure water pump → Micro-porous filter → Filling. 3. An ultrafiltration/nanofiltration process is used to produce mineral water. The process is as follows: Raw water tank → Pressure pump → Multi-media filter → Activated carbon filter → Pressure pump → Ultrafiltration → Intermediate water tank → Ozone sterilization → Finished product tank → Pressure pump → Micro-porous filter → Filling. Pre-treatment for reverse osmosis water purification systems: It consists of a fully automatic sand filter, a fully automatic activated carbon filter, and a fully automatic water softener. 　　1. Fully automatic sand filter: It consists of a fully automatic control valve, a fiberglass tank, and quartz sand in different gradation ratios. It can effectively remove suspended solids and some colloidal substances from the raw water, thereby reducing its turbidity. And it can perform backwashing automatically. Quartz sand filtration is a preliminary treatment carried out before water purification, in order to achieve good results during the purification process and improve water quality. This is because tap water contains a certain amount of impurities, such as sediment, rust, red worms, organic matter, microorganisms, and mechanical debris. The presence of these impurities severely affects the quality of the purified water and the efficiency of the treatment process. Therefore, it is necessary to reduce or remove certain impurities before the final purification step, which requires pretreatment. After pretreatment with quartz sand, impurities such as water turbidity, color, colloids, organic matter, iron, manganese, microorganisms, volatile substances, and dissolved gases can be removed or reduced to a certain extent. 　　2. Fully automatic activated carbon filter: The activated carbon filter consists of a fully automatic control valve, high-quality glass tanks, and activated carbon with different water purification levels. It can effectively adsorb harmful substances in raw water such as heavy metals, free chlorine, and chloroform. And it can perform backwashing automatically. Activated carbon is a weakly polar adsorbent with a well-developed pore structure and a large specific surface area. The internal surface area, which consists of micropores (with pore sizes less than 40 angstroms), accounts for over 95% of the total surface area; as a result, activated carbon possesses a high adsorption capacity. The disinfection of tap water is usually achieved by introducing chlorine into the water; to maintain its bactericidal effect, a residual chlorine level of 0.5–1 mg/L must be maintained throughout the water distribution network, with a residual chlorine level of 0.05–0.1 mg/L also required at the end of the network. Since the presence of residual chlorine can damage the structure of ion exchange resins, reducing their strength and making them prone to breaking, it is necessary to remove residual chlorine from tap water. Under normal conditions, activated carbon can adsorb and remove over 99% of the residual chlorine in tap water. In addition, the surface of activated carbon is equipped with a large number of functional groups such as hydroxyl and carboxyl groups, which enable it to carry out chemical adsorption of organic substances of various types, as well as through electrostatic attraction. Therefore, activated carbon can also remove organic compounds such as humic acid, fulvic acid, and lignosulfonic acid, which are harmful to anion exchangers, thereby improving the efficiency of desalination processes. It can typically remove 63%-86% of colloidal substances, about 50% of iron, and 47%-60% of organic matter. 　　3. Fully automatic food-grade water softener: A food-grade water softener is composed of a fully automatic control valve, high-quality fiberglass tanks, and food-grade resin. Food-grade water softeners can effectively remove calcium and magnesium ions from water. This prevents scaling from affecting the service life of the reverse osmosis membranes during the operation of the reverse osmosis equipment. Automatic regeneration for softening water treatment involves using the exchangeable cations in cation exchange resins to replace the calcium and magnesium ions present in water. This process can be represented by the following ion reaction equations: Ca2+ + 2RNa → R2Ca + 2Na+, Mg2+ + 2RNa → R2Mg + 2Na+. When the water flowing through the resin layer reaches a certain hardness level, the ion exchange resins become saturated and can no longer perform the softening function. To restore their exchange capacity, the resins need to be regenerated (also known as reduced). This system features fully automatic control, eliminating the need for manual intervention, and ensures stable water quality. 　　4. Safety filter: The safety filter serves as the final layer of protection before the raw water reaches the membrane. It can effectively remove substances larger than 5μm that leak during pretreatment. It is primarily to prevent suspended particles from entering the reverse osmosis membrane elements and depositing on their surface, thereby contaminating them. 　　5. Ozone: It is a broad-spectrum, highly effective, and rapid sterilizing agent that can completely eliminate bacteria and viruses from the finished water. 　　6. The reverse osmosis system is mainly composed of a high-pressure pump, a reverse osmosis membrane, and a control unit. The high-pressure pump pressurizes the raw water; aside from water molecules, which can pass through the RO membrane, other substances in the water (minerals, organic compounds, microorganisms, etc.) are almost entirely prevented from passing through the membrane and are carried away by the high-pressure concentrated water. The reverse osmosis unit is the core component for pre-desalination in this project; water treated by reverse osmosis can have the vast majority of inorganic salts, organic substances, microorganisms, etc., removed. The rationality of the design is directly related to the project’s investment costs, the economic efficiency of the entire system’s operation, its service life, and the ease of operation. The reverse osmosis membranes are all the world’s most advanced ultra-low pressure composite membranes, with a single-membrane desalination rate of 99.8%. When the system design temperature is 25°C, and taking into account factors such as variations in the quality of the raw water and the service life of the membranes, this system uses polyamide composite RO membranes installed within stainless steel pressure vessels. Recovery rate: 50-75%, desalination rate: 98%. Generally, after being treated by a first-stage reverse osmosis water purification system, the conductivity of the produced water is