Ultrapure water machines are increasingly used in laboratories and biopharmaceutical fields and have been applied to various companies and universities. However, ultrapure water systems must be replaced after a certain number of years of use, and require continuous maintenance during use. So how long is the service life of an ultrapure water system?
1. What is An Ultrapure Water System?
Ultrapure water system refers to a water treatment system that treats raw water to ultrapure water quality standards. A common ultrapure water system consists of multiple filtration, ion exchange, degassing, reverse osmosis, ultraviolet, ultrafiltration, electrodeionization, and other water treatment technologies to ultimately produce ultrapure water.
The ultrapure water system is a multi-functional, fully automatic equipment composed of pretreatment, reverse osmosis (RO) system, and electro-deionization (EDI) system. It is a fully automatic complete set of equipment with safe and convenient use, low operating costs, and stable water quality. The equipment is mainly used for centralized water supply in hemodialysis rooms, biochemistry rooms, dental clinics, central laboratories of supply rooms, preparation rooms, operating rooms, etc.
2. How Does an Ultrapure Water System Work?
The ultrapure water machine adopts automatic control (manual control can also be used at the same time), and the automatic backwash and regeneration programs can be set during system operation. The first-stage and second-stage reverse osmosis have reflux pipelines, and the reverse osmosis equipment is equipped with chemical cleaning and disinfection devices. The reverse osmosis membrane uses DuPont membrane imported from the United States to ensure the long-term stable operation of the reverse osmosis equipment.
The reverse osmosis pipeline adopts stainless steel and UPVC materials. Online conductivity meters are installed in the first-stage and second-stage reverse osmosis equipment, and the reverse osmosis system is equipped with low-pressure and high-pressure protection switches. The reverse osmosis water recovery rate is adjustable, with a recovery rate of 50-75% for first-stage reverse osmosis and 80-90% for second-stage reverse osmosis. The circulating transportation pipeline is equipped with ultraviolet sterilizers and microporous filters to ensure that the pure water meets hygiene requirements.
3. How Long Can An Ultrapure Water System Last?
Ultrapure water machines used in laboratories and pharmaceuticals require regular maintenance. The entire ultrapure water system is composed of multiple parts. Therefore, as the service life increases, the parts of the equipment will also age. If the consumables of the equipment are replaced and maintained regularly, the service life can reach 6-10 years.
The life span of ultrapure water equipment is usually affected by the following factors: incoming water quality, damage to membrane accessories, quality of internal parts, and timely equipment aging maintenance.
If the quality of the incoming water is poor, the consumption of consumables will be more serious. Especially the loss of the pretreatment system and reverse osmosis membrane. Although most ultrapure water equipment needs to be equipped with an automatic backwash function, the reverse osmosis membrane still needs to be replaced regularly.
Increased frequency of replacement of membrane accessories and internal parts will also increase input costs. In addition, if the equipment does not undergo regular maintenance, the damage to the life of the equipment will be irreversible.
4. How to Extend the Ultrapure Water System’s Lifespan?
Pure water machine uses reverse osmosis technology for water treatment. In addition to using stainless steel, UPVC, and other materials to improve the basic material guarantee of the equipment and pipelines used in reverse osmosis equipment, we can also perform preliminary purification of tap water in front of the reverse osmosis pure water machine. While meeting RO water quality requirements, we can also protect the reverse osmosis RO membrane so that It functions properly and extends its service life.
Improvements in ultrapure water machine treatment can be made through the following components.
（1） Selection of Melt-Blown Filter Elements
Melt-blown filter elements can filter out suspended particles in water larger than 5-10μm. The aperture size is non-uniform, and the number of apertures of different sizes follows a normal distribution, with a large value (peak) occurring at 5-10μm. The diameter of the fiber and pore size of the PP fibers are related to factors such as the melt temperature, indoor air temperature and humidity, airflow size and speed, and receiving distance.
High-quality melt-blown filter elements have progressively denser pore sizes from the outside to the inside of the PP fiber, with a large number of impurities filtered out on the surface and inside of the filter element, and have a high pollution absorption capacity and long service life. However, the manufacturing equipment is complex and expensive, and the price of filter elements is high.
（2） Use of Ceramic Filter Elements
Although melt-blown filter elements are inexpensive, they are disposable. Ceramic filter elements can be used instead of melt-blown filter elements. Although ceramic filter elements are more expensive and require a larger initial investment, they can be repeatedly cleaned and have a much longer service life. As long as the design of the entire machine considers easy filter element installation and removal, using ceramic filter elements instead of melt-blown filter elements is a good choice.
The raw material used for ceramic filter elements should be diatomaceous earth, which is fired in a tunnel kiln. The ceramic filter element should be light in weight, have good water absorption, and have high porosity. Poor-quality ceramic filter elements have a relatively rough and uneven surface and are heavier due to impurities. Another simple method is to drip water on the surface of the ceramic filter element. If the water is quickly absorbed and no droplets remain on the surface, it indicates good hydrophilicity and high porosity.
（3） Microfiltration-Ultrafiltration Dual Membrane Method
Some water purifier manufacturers use a combination of hollow fiber microfiltration – granular activated carbon – hollow fiber ultrafiltration for the pre-treatment stage, which is a good combination.
The first stage uses a PVDF hollow microfiltration membrane with enhanced support to remove suspended solids and bacteria. The membrane can be removed and rinsed if it becomes dirty, and will not break. The second stage uses activated carbon to remove residual chlorine, organic matter, colloids, odors, and more. The third stage uses a PS hollow ultrafiltration membrane to further remove suspended solids, microorganisms, and colloids. This thorough pre-treatment not only extends the service life of the RO membrane but also increases the recovery rate of pure water.
（4）Activated Carbon Fiber Filter Element
Activated carbon fiber (ACF) is made from viscous fiber or polyacrylonitrile-based fiber with a fiber diameter of about 10-20μm. The average pore size of the micropores is 17-26A for the former and 10-20A for the latter. Activated carbon fiber is often made into a felt that is 1-5mm thick. It has more micropores than granular activated carbon and is larger.
（5）Granular Activated Carbon Filter
Activated carbon has a significant role in removing residual chlorine, adsorbing colloids and organic matter, removing odors, and protecting reverse osmosis membranes. Its performance is mainly reflected in its ability to remove COD. The ability to remove COD is related to the flow rate and contact time design of the water purifier. According to the JB/T2932 “Technical Conditions for Water Treatment Equipment” standard, the filter can remove the residual chlorine in water (the effluent residual chlorine Ag2+ > Ag+, inhibiting bacterial growth and ensuring that the silver ion content in water does not exceed the standard).
（6） Purification Column
A purification column sometimes called an ultra-purification column, is designed to deeply desalinate reverse osmosis purified water to achieve primary or ultra-pure water levels based on the customer’s water quality needs. The principle behind it is ion exchange. The lifespan of the purification column is indicated by the online resistivity. If the resistivity is below a certain specific level, it means that the purification column has expired, which is a straightforward indication. In addition to the amount of water used, the filling amount of the ion exchange resin and the quality of the resin itself during production and design by each manufacturer are especially important factors in the lifespan of the purification column.
（7）Installation of Pressure Relief Pump
When the water pressure is too high, a pressure relief pump must be installed. If the incoming water pressure is consistently higher than 0.3 MPa or the pressure fluctuates greatly, it may cause damage to the ultrafiltration membrane. Therefore, a pressure relief pump should be installed when necessary to ensure that the water pressure reaches the normal working standards of the water purifier.
5. How to Maintain Your Ultrapure Water Systems？
Firstly, the machine must be operated correctly according to the correct procedure, and secondly, its maintenance and upkeep must be done to make its performance more stable. The filter cartridges used to filter the water quality in the ultra-pure water machine are consumables and have a certain service life. If consumables are not replaced in a timely manner, the entire system’s operating status will be poor, resulting in a gradual decline in performance.
Therefore, during the daily use of the system, it is necessary to strengthen the supervision of the machine’s performance indicators and identify problems in a timely manner to resolve them. For example, regularly cleaning the reverse osmosis equipment can remove residual pollutants from the equipment and extend the life of the pure water machine.
6. Final Words
Choosing the right manufacturer can extend the service life of ultrapure water equipment. As a manufacturer engaged in the design and development of professional ultrapure water systems, we guarantee to provide our customers with the best technical support and perfect after-sales service.
NEWater has been committed to the development and innovation of ultrapure water systems for 20 years. We can provide you with factory-priced laboratory ultrapure water systems, RO + EDI ultrapure water systems, laboratory deionization systems, etc. Our goal is to provide high-quality ultrapure water machines to more users.