First, 15 tons / hour large-scale industrial two-stage reverse osmosis RO water device _ principle and composition of water treatment
The working principle of industrial two-stage reverse osmosis RO water production device is to remove impurities and pollutants in the raw water through the filtration effect of two-stage reverse osmosis membranes, as well as possible pre-treatment and post-treatment steps, so as to obtain high-purity water. The working principle of the industrial two-stage reverse osmosis RO water production unit is mainly based on the selective permeability of the reverse osmosis membrane. The following is a detailed description of the working principle:

1) Pre-treatment system:
Raw water first enters the pretreatment system, which usually includes multi-media filters, activated carbon filters, softeners (if the water hardness is high) or scale inhibition and dosing devices and security filters. The role of these devices is mainly to remove large particles of impurities in the water, organic matter, residual chlorine and reduce water hardness to protect the subsequent reverse osmosis membrane from contamination and damage.

(2) a reverse osmosis device:
The pre-treated water enters the primary reverse osmosis system. Here, a high-pressure pump increases the water pressure to a pressure higher than the osmotic pressure, and then the water passes through the first-stage reverse osmosis membrane. The reverse osmosis membrane only allows water molecules to pass through, while most of the salts, organic matter, microorganisms and other impurities are retained on one side of the membrane, thus realizing the initial purification of water.

3) Dosing system:
In the two-stage reverse osmosis system, we in order to improve the desalination rate of reverse osmosis, to further improve the quality of the effluent water or to meet specific needs, the effluent of the first stage of reverse osmosis may go through pH adjustment and other intermediate treatment steps.

4) Secondary reverse osmosis stage:
After primary reverse osmosis and possible intermediate treatment the water enters the secondary reverse osmosis system. Here, the water is again pressurized by a high-pressure pump and passes through a second-stage reverse osmosis membrane. The second stage reverse osmosis membrane further removes residual impurities from the water, including viruses, bacteria and other particles, resulting in a higher purity effluent.

5) Produced water and concentrated water discharge:
Eventually, the high purity water after the two-stage reverse osmosis treatment is collected and supplied to the water point. Meanwhile, the concentrate (concentrated water) produced during the reverse osmosis process is treated or recycled through the discharge pipeline.
Second, 15 tons / hour large-scale industrial two-stage reverse osmosis RO water plant _ water treatment advantages and disadvantages of the analysis is as follows:

Advantages
(1) high purity water quality: two-stage reverse osmosis membrane technology can remove more than 98% of the dissolved salts in the water and more than 99% of the colloids, microorganisms, particles and organics, etc., and the output of water is of high quality, which is suitable for the industrial field with very high requirements for water quality.
(2) energy saving and environmental protection: the device usually adopts fully automatic control, low energy consumption and high stability. Although the initial investment is high, but the long-term operating costs are relatively low, and is conducive to resource conservation and environmental protection.
(3) small footprint: compact equipment, small footprint, easy transportation and on-site installation and commissioning, suitable for a variety of industrial environments.
(4) easy to operate: fully automatic control system makes the equipment easy to operate, the user only needs to set the relevant parameters, the equipment can run automatically, reducing the operating difficulties and labor costs.
5）Strong adaptability: the device can adapt to the environment of different water quality, purify the incoming water through the pretreatment system, ensure the stable operation and prolong the service life of the reverse osmosis membrane.

Disadvantages 
High initial investment: the initial investment of industrial two-stage reverse osmosis RO water production device is usually high, including the purchase cost of membrane components, high-pressure pumps, pretreatment equipment, control systems and so on.
Operation and maintenance costs: In order to maintain stable desalination performance, membrane elements need to be replaced and equipment maintenance on a regular basis, which is a considerable expense. At the same time, the cleaning and maintenance of equipment also requires a certain cost and time.
High water quality requirements: RO membrane pore size is very small, easy to be suspended particles, colloids, microorganisms and other pollutants clogging, so the feed water quality requirements are strict. Need to be equipped with a comprehensive pretreatment system to purify the feed water, increasing the complexity and cost of the system.
Energy consumption: Although the energy consumption is lower than traditional desalination technology, the RO process still requires higher operating pressure and consumes a certain amount of electricity. This can be a limiting factor in areas with energy constraints or high electricity prices.
Concentrated water discharge problem: The concentrate (concentrated water) produced by the RO process contains high concentrations of salts and other pollutants, and in wastewater treatment, direct discharge can have a negative impact on the environment. It is necessary to handle the concentrated water properly, such as through recycling, deep treatment or comprehensive utilization to reduce its environmental impact.

Third, 15 tons / hour large industrial two-stage reverse osmosis RO water device  water treatment selection and considerations
(1) understand the water quality needs: in the selection of industrial two-stage reverse osmosis RO water device, you first need to understand the required water quality standards and water requirements. Different industrial areas have different water quality requirements, so you need to select according to the actual situation.
(2) Examine the strength of manufacturers: choose manufacturers with professional R & D team, advanced production equipment and rich after-sales experience to cooperate. This will ensure the quality of the equipment and after-sales service quality.
3) Focus on equipment performance: understand the key performance indicators such as water production, desalination rate, recovery rate, etc., and ensure that the equipment meets the relevant standards and regulatory requirements. At the same time, you also need to pay attention to the operational stability and durability of the equipment and other aspects.
(4) Consider the cost of maintenance: When choosing equipment, you also need to consider its subsequent maintenance costs and the ease of replacement parts and other factors. Selecting equipment that is easy to maintain and replace parts can reduce the later operating costs.