Knowledge of Water Treatment Equipment

Author: Hongjie Water

1、 Working principle and process flow

Utilizing membrane technology as the core filtration material, supplemented by pre-treatment or other equipment, to achieve purification purposes.

Secondary reverse osmosis purified water process flow: 

Raw water - quartz sand filter - activated carbon filter - security filter - multi-stage pump - primary reverse osmosis membrane (concentrated water recovery) - multi-stage pump - secondary reverse osmosis membrane (concentrated water recovery) - purified water

Primary reverse osmosis purified water process flow:

Raw water - quartz sand filter - activated carbon filter - security filter - multi-stage pump - primary reverse osmosis membrane (concentrated water recovery) - purified water

Mineral water, mountain spring water, and water purification process flow:

Raw water - quartz sand filter - activated carbon filter - security filter - ultrafiltration membrane - mineral water, mountain water

Process flow of Ultrapure water and deionized water:

Raw water - quartz sand filter - activated carbon filter - security filter - multistage pump - primary reverse osmosis membrane (concentrated water recovery) (or secondary reverse osmosis process) - primary mixed bed equipment - secondary mixed bed equipment - Ultrapure water

2、 Introduction to filters and filter elements at all levels

1. Quartz sand filter:

The filter is filled with refined multi-layer and multi diameter quartz sand, effectively removing sediment, rust, large impurities, and suspended particles, and improving the inlet water quality. The filter can be manually flushed back and forth, and the filter element has a long service life. In theory, there is no need to replace it, only a small amount of supplementation is needed. There are two types of materials for the filter casing, one is stainless steel material, and the other is fiberglass material. The filling capacity of the filter material varies from 150 kilograms to 3000 kilograms depending on the processing capacity.

2. Activated carbon filter:

Activated carbon filters are mainly used to remove organic matter and residual chlorine. The filter is filled with purified activated carbon (mainly fruit shell activated carbon), and the filtered water enters the activated carbon filter. Firstly, it adsorbs some organic substances in the water, with an adsorption rate of about 60%; The second is to adsorb residual chlorine in water. The removal of residual chlorine by activated carbon is not simply an adsorption process, but a catalytic effect occurs on its surface, so there is no adsorption saturation problem with activated carbon, only a loss of carbon. There are two types of materials for the filter casing, one is stainless steel material, and the other is fiberglass material. The filling capacity of the filter material varies from 50 kilograms to 1000 kilograms depending on the processing capacity. After being adsorbed by activated carbon, the effluent has basically met the inlet water requirements of the RO device: SD1 ≤ 4;

3. Security filter:

The security filter is equipped with a PP20-30 filter element, which filters out finer impurities and particles to prevent particles from entering the high-pressure pump and RO membrane components and scratching the membrane surface. Under normal working conditions, the filter element can maintain a service life of more than 3 months, and the structure of the filter meets the requirements for quick replacement of the filter element. The outer shell of the filter is made of stainless steel, and the filter elements vary from 3 to 12 depending on the processing capacity.

4. Reverse osmosis membrane filter:

Reverse osmosis membrane is the heart part of purified water equipment. The water treated by RO reverse osmosis device can remove the vast majority of inorganic salts, all organic matter, harmful chemicals, pesticide residues, bacteria and viruses, making its water quality meet the standard of purified water. According to the requirements for effluent quality, it can be further divided into primary reverse osmosis treatment and secondary reverse osmosis treatment. After secondary reverse osmosis treatment, the desalination rate of water is over 99%, and the utilization rate of water is over 60%. The water quality meets the national standard for bottled pure water. The reverse osmosis membrane is generally used by the American company Heidelberg, with two specifications: 4040 and 8040. Depending on the processing capacity, there are 1-20 units with a service life of over 2 years.

5. Ultrafiltration membrane filter:

Hollow fiber ultrafiltration membrane is the heart part of mineral water equipment. The water treated by ultrafiltration device can remove the vast majority of bacteria and almost all organic matter, microorganisms, and make its water quality meet the water purification standard. The utilization rate of water has reached 75-90%, with a large processing capacity and is not easy to block. Currently, domestic membranes are used, and there are also two specifications: 4040 and 8040.

6. Mixed bed equipment:

Using anion and cation resin as filter material to remove anions and cations from water, in order to achieve the goal of being purer than pure water. The filter material in the mixed bed is divided into two types: renewable and non renewable. The cost of using renewable filter materials will be lower, and the mission of non renewable filter materials will be longer. The water treated by the mixed bed is called Ultrapure water. The unit of measurement is resistivity. The resistivity is the inverse ratio of conductivity. Generally, the resistivity of water treated by the mixed bed is between 1-15 megohm.

3、 Complete equipment configuration of purified water plant:

1. Secondary reverse osmosis water making machine:

According to QS certification requirements, the water production equipment of the purified water plant must be at least 1T/H. Therefore, the customer's needs are generally above 1T, with options such as 1T, 2T, and 5T. The equipment of the purified water plant must be a secondary reverse osmosis to meet the effluent requirements, which means that the conductivity is less than 10.

2. Fully automatic bottle washing and filling machine:

It is a specialized equipment used for cleaning purified water barrels and filling purified water. It adopts a pneumatic device and operates fully automatically from external washing to filling and sealing. The cleaning process generally involves four stations of cleaning: external cleaning - internal cleaning - disinfectant cleaning - pure water cleaning, followed by filling and capping; According to the different filling capacity, it can be divided into single row and double row. Generally, filling 60 to 120 bottles per hour is single row, and filling more than 120 bottles is double row (such as: 200, 400); It can be divided into linear and L-shaped according to its different appearance.

3. Stainless steel water storage tank:

The purified water filtered by the reverse osmosis water making machine should be stored in a stainless steel water storage tank, disinfected and preserved before filling. The water storage tank is generally divided into several specifications such as 1T, 2T, 3T, and 5T, with a liquid level switch that is connected to the water making machine to achieve automatic water inlet and shutdown. The material is 304 food grade stainless steel, and the bracket can be made of iron or stainless steel.

4. Ozone aquatic organism:

Using purified water as raw material, ozone disinfection and preservation of purified water are generated through electrolysis of purified water. The advantage of this equipment is that no other raw materials are needed and there is no pollution; The disadvantage is low ozone production, lack of mixing equipment, and insufficient disinfection. Generally used for water production equipment below 1T.

5. Ozone mixer:

Stainless steel frame, made of medical oxygen as raw material, generates ozone through electrolysis of oxygen, and then uses a mixing pump to fully mix ozone and purified water to form a milky white gas-liquid mixture, achieving complete disinfection and preservation effects. This device produces a large amount of ozone and has good disinfection effect, and is generally used for water production equipment with a capacity of over 1T. Ozone is a highly oxidizing gas with a special odor. During the storage process of pure water, ozone will naturally decompose into oxygen and free oxygen. Therefore, bottled water usually needs to be stored for more than 12 hours before sale to facilitate ozone decomposition.

6. Air purifier:

It is specifically used to purify the air in the filling room, ensuring that the air cleanliness in the sealed filling room reaches level 1000 or above, and eliminating secondary pollution during pure water filling. Depending on the size of the filling room, one or two units can be selected.

7. Bottle cap disinfection cabinet:

It is specially designed for disinfecting bottle caps, with a stainless steel structure and two types of disinfection facilities, ozone and ultraviolet, to ensure that bottle caps are pollution-free.

8. Automatic sealing machine (optional)

Installed behind the filling machine, using water vapor as energy to seal the heat shrink film on the bottle mouth. The specifications range from 60 to 300 bottles per hour, equipped with plastic chain plates.

9. Fully automatic water softener (optional)

Specially used in areas with hard raw water quality, it removes calcium and magnesium ions from water through ion exchange, achieving the goal of softening water and protecting RO membrane from scaling and blockage. Generally, if the hardness of the raw water exceeds 500, a water softener should be installed. Depending on the amount of water produced, a water softener with a processing capacity of 2-35T per hour can be selected.

10. Air shower room (optional)

Specially used for disinfecting operators before entering and exiting the filling room, to avoid human contamination of the air in the filling room.

4、 Complete equipment configuration for mineral water and mountain spring water plants

1. Ultrafiltration water purifier

The core technology is ultrafiltration membrane, which utilizes its larger pore size than reverse osmosis membrane to filter impurities and bacteria while retaining natural minerals in mineral water. The entire machine is made of stainless steel structure, luxurious and beautiful, equipped with large flow rate pre-treatment, and the water production capacity ranges from 1T to 15T.

2. Other equipment is the same as the "configuration of purified water plant equipment", except for water softeners.

5、 Ultrapure water equipment configuration

1. Primary or secondary reverse osmosis water making machine

As the pretreatment of Ultrapure water equipment, most impurities, bacteria and ions can be removed. Ensure the desalination rate of subsequent equipment.

2. Primary or secondary mixed bed

Further remove ions from water using anion and cation resins to achieve the required electrical resistivity for use.

3. Stainless steel water storage tank

It is used to store Ultrapure water.

4. Stainless steel Booster pump

It is used to pressurize the Ultrapure water in the water storage tank and deliver it to the designated work site.

6、 Unit pure water equipment configuration

1. Primary or secondary reverse osmosis water making machine

Unit use: firstly, internal drinking water and canteen water; The second is manufacturing process water, such as tableware disinfection companies using it to clean tableware. Generally, secondary reverse osmosis equipment is used in the north, and primary reverse osmosis equipment is used in the south. The general dosage is around. 3-1T/H, and can be configured with fiberglass or stainless steel.

2. Stainless steel water storage tank

3. Stainless steel Booster pump

4. Ozone aquatic organism

7、 The difference between large equipment and household and commercial pure water machines

1. Domestic and commercial pure water machines are all primary reverse osmosis, and there are two types of large equipment: primary and secondary.

2. The water volume of household and business pure water machines is relatively small. The Unit of measurement is how many gallons per day. The actual consumption can only be calculated by 6-8 hours. It can not work for a long time. It needs to be equipped with a special pressure bucket; The large equipment has a large amount of water. The Unit of measurement is how many liters per hour. It can work continuously for more than 10 hours without the need for a pressure bucket.