Introduction to the replacement cycle and basis for consumables of purified water equipment

Familiar with and master the maintenance standards of purified water equipment and effective implementation, is the long-term stable operation of the equipment, the effective guarantee of continuous water supply, of which the timely and effective replacement of equipment consumables, is an important measure
to ensure water quality.

The consumables that need to be replaced and maintained regularly in purified water equipment are quartz sand, activated carbon, softening resin, PP filter element, RO membrane, EDI module, respirator filter element, ultraviolet lamp, seal\diaphragm
.

As the main filter material, quartz sand is used to filter out fine particles, suspended solids, colloids and other impurities
in raw water.

Avoid contamination of THE RO membrane element leading to a decrease in
water production.

When the system is running, a large number of suspended solids are intercepted, which increases the pressure difference between the filter in and out of the water, and the cumulative time of the system operation reaches 24 hours (which can be set according to the raw water quality), and the filter needs to be cleaned
.

The replacement cycle of quartz sand is 1 to 2 years, depending
on the quality of the raw water.

The main replacement basis is that the inlet and outlet water pressure difference is too large, and the normal value cannot be reached after multiple cleaning; The SDI value of the water quality >5, and the SDI value cannot be reduced to the normal range after multiple cleanings; The service life of quartz sand has exceeded the service life provided by the manufacturer; Fig.
1 Consumables replacement reference table activated carbon, the main replacement of the water pressure difference is too large, after multiple cleaning can not reach the normal value; Residual chlorine value of water quality>0.
05mg/L; The service life of activated carbon has exceeded the service life provided by the
manufacturer.

The role of activated carbon is mainly generated by adsorption, which can remove macromolecular organic matter, iron, oxides, and residual chlorine in the water, and protect the RO film from oxidation
.

A large amount of organic matter is intercepted during the system operation, which increases the pressure difference between the inlet and outlet of the filter, and the cumulative time of the system operation reaches 24 hours (which can be modified according to the raw water quality) and the filter needs to be cleaned
.

Because of the special shape structure of activated carbon, it is easy to become a warm bed for the growth of bacteria and microorganisms, and if it is not controlled, it will lead to the contamination
of RO film and EDI.

Therefore, activated charcoal should be disinfected once
in 1-3 months.

Hot water disinfection is usually used, which can kill microorganisms
in the water very well.

The activated carbon replacement cycle is 8 to 12 months, depending
on the quality of the raw water.

The main replacement basis of the softening resin: the inlet and outlet water pressure difference is too large, and the normal value cannot be reached after multiple cleanings; Resin poisoning and oxidation cause the hardness of the water produced to > 0.
03mmol/L, and the hardness of the produced water after regeneration cannot reach the normal value; The service life of the resin has exceeded the service life provided by the
manufacturer.

The role of softening resin is mainly manifested in the use of sodium-type cation exchange resin to remove calcium and magnesium ions in water, reduce the hardness of raw water, prevent scaling on the surface of reverse osmosis membrane, and affect water production and use performance
.

The system runs to the resin to absorb a certain amount of calcium, magnesium ions will no longer be exchanged, the system needs to use NaCl to regenerate the resin, the system running accumulation time or flow rate to reach the set value (can be set according to the raw water quality), usually the system automatic mode is completed, because the softening regeneration time is longer, in the system selection to avoid purification water supply is insufficient, you can consider the double softening process
.

Because the resin is easy to become a warm bed for bacteria and microorganisms, the system should be disinfected once every 1-3 months, and it is recommended that the hot water disinfection method be more effective
.

The resin replacement cycle is 1 to 2 years, mainly according to the quality of the raw water
.

Figure 2 The role of the security filter element of the net DERUI purified water equipment is to prevent the ≥ 5μm particles from entering the reverse osmosis membrane by using a PP cotton column filter element, resulting in easy contamination and scratching
of the RO membrane.

Important monitoring indicators: inlet and outlet water pressure difference <0.
05MPa, filter pollution status<b138>.

Whether the filter element, joints and seals are deformed or damaged and lead to failure, the spare parts
should be replaced in time.

The filter replacement cycle is 1-3 months, mainly according to the quality of the raw water
.

The main replacement basis: refer to the difference in inlet and outlet water pressure of
the filter.

The service life of the filter element reaches the manufacturer's recommendation or the internal replacement cycle time of the
enterprise.

Reverse osmosis system with the help of reverse osmosis membrane to select the function of permeable (semi-permeable) membrane, with the pressure difference as the power of the reverse osmosis membrane, filter the impurities in the inlet water, such as ions, organic matter, bacteria, viruses and other substances, so as to achieve the purpose of separation and purification, to achieve low conductivity of water quality
.

In order to avoid fouling and fouling on the concentrated water side of the reverse osmosis membrane, the reverse osmosis system should be flushed with a fixed cycle and rinsed before shutdown and before start-up to extend the chemical cleaning cycle time
of the reverse osmosis membrane.

Reverse osmosis membrane is an important component of the purified water system, enterprises should analyze changes in system performance according to daily spot inspection data, so as to prevent in advance and avoid irreparable damage
.

When any of the following changes are found in the operating data, the reverse osmosis membrane needs to be chemically cleaned
.

The replacement cycle of reverse osmosis membrane is 2-4 years, depending
on the water quality and operating conditions.

The main basis for replacement: the performance of the reverse osmosis membrane is reduced, and the performance cannot reach the normal range
after chemical cleaning.

When the reverse osmosis membrane is irreparable damage, it affects the operation of the
system.

The service life of the reverse osmosis membrane has exceeded the service life provided by the
manufacturer.

Fig.
3 The continuous electrodeionization equipment of the purified water equipment of NetDerui is referred to as EDI, which realizes the directional migration of ions in water under the action of the electric field through the selective transmission of cations by anionic membrane and the exchange of ions in water by the ion exchange resin, so as to achieve the purpose
of deep desalination of water.

It should be noted that EDI is divided into temperature-resistant type and normal temperature type, and temperature-resistant EDI is regularly disinfected by pasteurization
.

The replacement cycle of EDI is 3-5 years
.

The main replacement basis: EDI performance is reduced, after chemical cleaning performance can not reach the normal range
.

The service life of EDI has exceeded the service life provided by the
manufacturer.

The main basis for the replacement of the respirator filter element, the normal production situation of the enterprise, continuous monitoring and analysis of integrity test data, to confirm the internal replacement cycle standards
.

The service life of the filter element has exceeded the service life provided by the
manufacturer.

Its role lies in the use of filtration accuracy ≤ 0.
22μm hydrophobic PTFE material filter element
.

Filter the air to avoid airborne particles and microorganisms from entering the terminal water tank and causing the terminal water to be contaminated
.

Replacement cycle: The replacement cycle of the respirator filter element is 6-12 months; The role of the ultraviolet sterilizer is to use 245 nm wavelength of ultraviolet light to effectively kill free microorganisms in the water and extend the disinfection cycle of
the distribution system.

Among them, the TOC remover, with a wavelength of 185nm ultraviolet light, can effectively remove the total amount of organic carbon in the water and improve the quality
of the water produced.

Important monitoring indicators: radishity replacement cycle: the replacement cycle of ultraviolet lamps is 6000-8000 hours, the main replacement basis: when the use time of ultraviolet lamps is extended, ultraviolet light gradually weakens below 80% of the initial value intensity; The service life of UV lamps has exceeded the service life
provided by manufacturers.

In the content of the consumable replacement piece, there is also an important point that in order to purify the safe and stable operation of the water system, it is recommended to use the original brand consumables of the system when replacing important consumables
.

If you need to replace consumables of different brands, models or materials, you should control the change
.

Planned periodic and preventive maintenance should be traceable and maintenance costs
effectively controlled.

Each replacement of consumables should be done with relevant replacement records and test records of water quality before and after production
。