Seawater desalination plant with "Russian Maritime Register of Shipping" certificate
1. Why do we need water treatment units on ships
2. Water treatment stages
3. Conclusions
Sea, river vessels or yachts are complex mechanisms where everything must work according to certain instructions and comply with regulations. One of the important systems is water treatment devices. After all, it is important not only to obtain clean water, but also to maintain its quality. Water can contain many harmful elements that will affect not only health, but also equipment.
1. Why do we need water treatment units on ships?
Fresh, clean water is needed on yachts at all times. This applies to almost any type of water transport. But carrying large volumes with you is simply unprofitable. Firstly, you never know exactly how much water will be needed, only approximate figures. And secondly, such tanks will take up a lot of space. In addition, water can become infected with bacteria if it stays in the tank for a long time. Especially if the tanks used do not meet the standards.
Water must meet certain requirements and GOST 2874-82 "Drinking water. Hygienic requirements and quality control". In addition, mandatory wastewater treatment is required. The main purpose of purification is to remove existing contamination of the water supply system. It is necessary if the operating conditions are violated, and the water does not meet the standards. When stored for more than 10 days. If someone from the crew is diagnosed with intestinal diseases.
Mandatory treatment is also required after repairs or construction, when carrying out work on the water supply system, when the quality of water deteriorates or when using water in ports with an unfavorable epidemiological situation.
2. Water treatment stages
Ship purification units can have different configurations. This depends on the purpose of the system and the filtration level. The system performance is also taken into account. If we consider the full filtration cycle, it includes several purification stages.
At the first stage, mechanical impurities are removed. This can be silt, dirt, scale and other contaminants. This preliminary treatment is necessary not only to correct the composition of the water, but also to protect subsequent filters.
Fig. 1 Seawater desalination plant
The second stage involves the elimination of the main elements. These can be chlorine compounds, iron, manganese, calcium and magnesium salts, and other impurities. Various filters with sorbents or ionic resin are used for this. Most often, reverse osmosis systems are installed, which have been used for desalination for a long time. The last stage is water disinfection, that is, the elimination of bacteria and viruses. Previously, an ozonizer or chlorination method was used for this. In principle, you can still find such a system. But most modern installations disinfect using ultraviolet lamps. They are completely safe, environmentally friendly, and effective.
The installation of the system is carried out by specialists. It is quite simple, but it is important to connect all the elements in the correct sequence and check the connections.
How is the equipment installed? Each configuration has its own installation instructions. But there are general points for any type of equipment. The system is firmly fixed. An important point is that it is necessary to leave space for servicing the device. Then the grounding is connected. If the kit includes softening and iron removal cartridges, they are installed. Then the system is connected to the main line and water is supplied. An important point will be checking for leaks. If such a situation occurs, then it is necessary to carry out a pressure test. To do this, shut off the water supply and release the pressure in the system. All gaskets are checked. The entire sequence of actions is repeated until the tank is completely sealed.
Next, the unit is connected to the power supply and external emergency sensors. Then the control cabinet is connected, water is supplied to the unit. All indicators must work in normal mode. If malfunctions occur, refer to the instructions. The main methods of desalination on yachts are ion exchange columns and reverse osmosis systems.
Desalination by reverse osmosis. The element that removes salts and other impurities is a semipermeable membrane. Passing under pressure, up to 60 bar, all impurities are removed from the water flow. Purified water enters the storage tank. The remaining concentrate is disposed of in the sea. The advantages of such desalination are obtaining water of the highest quality of purification, which is suitable not only for drinking, but also for any other purposes. The units are small-sized and do not take up much space. In addition, no chemicals are used during desalination. And the technical components of the water do not change after filtration. The disadvantages include the service life of the membrane. To extend the service life of the element, additional filters are installed to prepare the water. Semi-permeable membranes for desalination are more reinforced, due to which they can withstand increased loads and are protected from the negative effects of impurities.
Fig. 2 Reverse osmosis system
Desalination with ion plants. In this case, a special synthetic resin is used. It looks like small balls with a certain charge. When the flow passes, the salt ions are replaced by safe elements. The positive aspects of the method are its safety and the quality of desalination. The resin is washed by regeneration with a concentrated solution.
3. Conclusions
Marine water purification plants are a very important element. In order for the system to work effectively, it is worth paying attention to the correct operation. And the creation of optimal filtration conditions. The initial flow must have a certain pressure if a reverse osmosis unit is purchased. The approximate range is from 20 bar. The water temperature should not exceed +45 degrees. Filtration equipment is selected based on several parameters. First of all, the performance of the unit is important. If the yacht or boat is small, then systems that operate on 12/24 V are suitable for desalination. Such devices do not take up much space. However, they produce up to 100 liters of water every hour with a high degree of purification. Secondly, the purpose of the water. If drinking water purification is required, then it is mandatory to equip the system with pre-filtration cartridges.
Desalination plants for yachts require certain control and regulation according to standards. This function is performed by automatic controllers. The entire desalination system on yachts is fully automated, without human intervention. Equipment maintenance is mandatory. Despite the fact that it can operate smoothly for a long time, mandatory inspection of the equipment is required. The terms are specified in the device passport or in the instructions. Such systems require periodic flushing or replacement of elements. If these requirements are not met, the efficiency will significantly decrease and the quality of the water will deteriorate. And if it does not meet the standards, it cannot be used.
It is also necessary to create certain conditions for the operation of the device. The systems must be securely fastened so that they remain in place during the voyage. The disinfection unit must be protected from any mechanical damage. The unit must be grounded. Otherwise, it cannot be worked with. Any work with the system must be carried out with the power supply disconnected. The same applies to failures in operation. In case of emergency situations, the installation is switched off and the water supply is cut off.
