A Coolant for Wind Power
Wind is one of the pollution-free energy sources, and it is inexhaustible. With the development of the global economy, the wind energy market has also developed rapidly.With the development of technology and environmental protection, wind power generation can compete with coal-fired power generation in business.China is rich in wind energy resources, and the exploitable wind energy reserves are about 1billion kW. At present, wind power projects are all over the country.
With the investment of a large number of wind power generation equipment, some problems have been found during long-term operation.The power generation efficiency is reduced and the liquid cooling system is corroded.This is mainly because the cooling system is essential in wind power generation, and even affects the power generation efficiency.The main cooling systems include:1. In the unit including the gearbox, the gearbox has a set of gear oil cooling system;2. The generator has its own cooling system, such as cooling fan, natural air cooling, etc; 3. In the unit containing the converter system, there is also the cooling system of the corresponding converter system, which adopts different cooling methods, such as air cooling and water cooling;4. For the cooling system of the whole machine, in order to solve the problem of excessive temperature in the fan room, the fan has a set of cooling system as a whole, such as the overall air cooling system with chimney effect;5. Cooling system for other equipment.
The coolant of the existing cooling system mainly adopts ethylene glycol products, but there is no coolant specially developed for wind power generation equipment.Only some automobile antifreeze sold on the market can be used.However, there are still many differences between the materials and working conditions of automobile application and wind power generation, and the antifreeze has a service life.After finding this problem, the Glacial Coolant began to carry out relevant development experiments.Firstly, the cooling system of wind power generation equipment is made of copper, iron, aluminum and other materials. There is a potential difference between the materials, which is prone to electrochemical corrosion when the conductivity is high. When the conductivity is very low, it corrodes some metals faster. On this basis, a low conductivity coolant is developed to achieve corrosion inhibition of different metals with excellent physical parameters.However, the coolant should be included in the maintenance scope of wind power during the use process. The electricity should be tested and adjusted and maintained in time. Lifelong after-sales maintenance of Glacier Coolant.
Application of Coolant in Ice Ball Cold Storage System
Ice ball type cold storage air conditioning system uses a cold storage tank containing ice balls to store cold.The shell of the ice ball is made of high-density polyolefin material and is filled with a cold storage solution with high solidification melting latent heat.And use the coolant to flow through the gap between the balls in the cold storage sample to exchange the cooling capacity with the ice ball. When using brine unfrozen liquid or evaporation coil to make ice, the brine or refrigerant is in the pipe and the cold storage is outside the pipe, while the coolant of the ice ball type cold storage system flows outside the pipe and the cold storage body is in the ball. The maximum heat transfer area can be released to achieve efficient wet cooling and cold storage. It is widely used in ice storage system.
The traditional coolant is ethylene glycol, which has low viscosity and high specific heat under service conditions, so it is also widely used. However, in the system used for many years, the coolant has been seriously corroded. During the use process, it is found that the efficiency of the cold storage system has decreased, and the surface of the ice ball is attached with rust and dirt.
By establishing the flow model of ice storage tank, some researchers conducted experiments on the flow direction, inlet flow rate and physical property parameters of the coolant, and found that the higher the inlet flow rate, the coolant flows in from the bottom and out from the top, the lower the viscosity of the coolant, and the larger the Nu number tested.In some practical projects, relevant processes have been adopted, but ethylene glycol has been used as coolant, and there is no more suitable product.Glacial Coolant LM-4 uses modified ethylene glycol, which has low viscosity, higher specific heat and similar density. It can directly replace the traditional ethylene glycol system without corrosion.For the ice ball storage system, the glacier coolant LM-4 is suitable. At present, the company has several applications, and the application effect is good.
Glacier Coolant focuses on the research and development of coolant and the application experiment of coolant system, and customizes exclusive coolant for different systems.
Application of Coolant in Constant Temperature Air Conditioning System
With the progress of science and technology, more and more venues need high-precision constant temperature and humidity air conditioning.At present, some universities and enterprises have precision laboratories, data center machine rooms, power distribution of the State Grid, precision instrument processing workshops, and plant culture environments in agriculture. The characteristics of precision air conditioning are constant temperature and humidity, timely feedback and self-tuning to cope with load fluctuations.
Precision air conditioners generally use indirect refrigeration, which controls thermal fluctuation with small temperature difference. In particular, PID regulation can be realized in control. Combined with frequency conversion control, indoor air outlet temperature and humidity will be stable to meet high process requirements.With the economic development of the north, its demand for compact air conditioning is also gradually increasing. However, in the mode used in the south, there is a risk of pipeline freeze damage in the north. Some air-conditioning manufacturers have adopted the antifreeze solution on the market to solve the antifreeze problem.However, with the long-term use, it is found that the stability of the system has decreased. The main reason is that the physical properties of the antifreeze are unstable.It is necessary to calculate the selection of equipment in the design stage of precision air conditioning, and the physical parameters of coolant are essential.The main function of antifreeze in the market is antifreeze. There are few physical property tests, and it is corrosive after a long time. Rust mud will accumulate at some heat exchangers or regulating valves, affecting regulation and heat exchange, resulting in instability of the air conditioning system.
Glacial Coolant is specialized in making coolant,It has been used in many and stable fields, such as medicine and chemical industry. It is a product developed in the industrial field.Upgrade high-end testing software such as physical property testing laboratory, mass spectrometer and chromatograph, and provide high-quality after-sales service.When the precision air-conditioning system studies the control to improve the accuracy, it needs to pay attention to some external conditions of the coolant, so as to achieve more stable high-precision control.
Analysis on The Development Direction of Cold Storage Refrigeration System in Carbon Emission
With the goal of carbon peaking and carbon neutralization, carbon emissions are gradually affecting various industries, especially large energy consumers.As an important material supporting facility, the energy consumption of cold storage has always been an important factor in its development. However, under the goal of double carbon, carbon emissions will affect its later development direction.
Carbon emission is a comprehensive concept, which involves the construction of cold storage, material consumption, energy consumption, material recycling and other carbon footprints.Among them, energy consumption and refrigerant supplement account for a large proportion. The development direction of cold storage is mainly around energy consumption and refrigerant.At present, domestic cold storage systems mainly include ammonia refrigeration system, freon refrigeration system and carbon dioxide refrigeration system.Each system is the product of the development of policy and technology, and its advantages and disadvantages are obvious.
The energy consumption of ammonia refrigeration system is the lowest, the GWP of ammonia refrigerant is 0, and its comprehensive carbon emission is the lowest.From the perspective of carbon emission, ammonia refrigeration system will always be used in the future.However, due to the toxic, flammable and explosive properties of its products, some places and environments have been restricted.
Freon refrigeration system has a high energy consumption and a high global warming index. In the pipe library of some barrel pump systems, the leakage supplement of refrigerant is large. Its carbon emission is higher than that of energy consumption, and the comprehensive carbon emission is particularly high.It will be gradually reduced in the future cold storage application. Because of its good safety performance, there are still many cold storages used at present.
The energy consumption of carbon dioxide system is equivalent to that of freon, but its GWP is 1. The carbon emission from leakage and supplement during operation is also small, and the comprehensive carbon emission is moderate. It is a product of replacing Freon storage.However, its physical properties are quite different from those of ammonia and Freon systems. In the application of cold storage, the maintenance requirements are high, and the low-temperature defrosting is constrained. We still need to continue to explore in the development of cold storage.
The coolant refrigeration system is an indirect refrigeration system. Its main function is to cooperate with the refrigerant system to reduce the system charge.It is combined with ammonia refrigeration system to reduce the level of hazard sources, and with freon to reduce carbon emissions. Its energy consumption is slightly higher than that of Freon system, and its comprehensive carbon emission is low. It is an essential supplement in the future application of cold storage.
The exploration of refrigerants has been ongoing. The characteristics of safety, low carbon, energy saving and low investment will also be the ultimate direction of the refrigeration system of cold storage.
Glacial Coolant on the coolant refrigerant system and its application.
Energy Consumption Control of Coolant System
The application of coolant system has been very common.For example, pharmaceutical chemical industry, refrigeration, HVAC, heat pump and other systems.As the leading enterprise of domestic coolant carrier, glacier coolant has been supplied by more than 2000 enterprises, including new projects and transformation projects. The use effect has been highly praised, but the energy consumption in the use process is different. The owner often mentions the matter of energy consumption. Through our field investigation and analysis, we provide the owner with some opinions on energy conservation and emission reduction.
The first control point is mainly in the design stage. It is necessary to design a matching coolant system according to the physical properties of the refrigerant, so that the coolant pump, refrigeration compressor and end heat exchange can operate at the most efficient point. Such a system is the best for energy saving.This method is only suitable for new projects or projects with complete refrigeration system transformation.
The second control point is the selection of coolant. The design institute has little understanding of the physical properties of coolant. Generally, the physical parameters of ethylene glycol or brine are queried, and the parameters obtained are often insufficient, which will have a certain impact on the calculation.Finally, there will be high energy consumption in the process of operation.The energy consumption of the reconstruction project is generally high, so it is particularly important to select a suitable coolant, which can directly reduce the energy consumption. It is not an exaggeration to say that it is also possible to save 50% energy.
The third control point is the daily operation and maintenance. During the operation process, there are often gases entering the system. The filter or system impurities lead to the increase of system operation energy consumption, which requires regular maintenance.The physical parameters of the coolant need to be tested every year and adjusted in time to ensure the stable and efficient operation of the system.
The operation energy consumption of the coolant system is a whole process control, and each link needs to control the energy consumption.
Under the concept of carbon neutralization, the cooling system also needs fine control.This process requires a close combination of the design unit, the owner and the coolant manufacturer. As a coolant manufacturer, glacier coolant provides cooling system solutions to track the whole process of the project and realize energy conservation and emission reduction of the system.
Function of Intermediate Water Tank of Coolant System
There are many liquid supply forms of coolant system. According to the requirements of the system, primary pump liquid supply system and secondary pump liquid supply system can be set.At present, the secondary pump liquid supply system is widely used. The most important part of the secondary pump liquid supply system is the intermediate circulating water tank. The size of the water tank has a great impact on the stability of the system and the energy consumption of the system operation.Here is some analysis on the function of the intermediate water tank:
The circulation mode of the intermediate water tank: the primary water tank circulates with the refrigeration host, and the secondary water tank circulates with the end cooling equipment. Generally, the primary side is a constant flow system and the secondary side is a variable flow system.
The requirements of the primary side for the water tank mainly involve the start and stop of the host. The host generally has a short loading time and cannot be started again after shutdown. The interval is generally not less than 15 minutes. Therefore, it is necessary to ensure the load at the corresponding time after the host is shut down.
According to the requirements of the secondary side for the water tank, the end load of the secondary side is not a stable value. It is necessary to ensure that the cooling load of the water tank can provide the end load during the use process or during the reaction time when the main engine is shut down and loaded.In this case, the system can operate stably, and there will be no temperature oscillation in both the host and the end.
In addition, how to save energy in the intermediate water tank also needs to be considered.Assuming that the water tank is an infinite carrier, it can be understood as a cold source with constant temperature. The host transmits the cooling capacity during off peak power, and the end obtains the cold source from the water tank at any time according to the production needs.The operation energy consumption of this refrigeration system is about to reach the lowest, and the selection of equipment can also choose an efficient refrigeration host, which is the most ideal energy-saving practice. However, the actual capacity of the water tank needs to consider its economy and the investment and return in a reasonable range. At least its static payback period is within 5 years.
To sum up, the selection of intermediate water tank needs to fully consider the attributes of the system and select a reasonable intermediate water tank to ensure the operation of the whole system. Glacial coolant focuses on the systematic application of coolant.
Selection of End Pipe Arrangement Form of Coolant Cold Storage
Low temperature cold storage usually use exhaust pipes as heat exchangers, and the external heat transfer forms are natural convection and radiation heat transfer.In general, multiple circulation of refrigerant is used for liquid supply in the pipeline, which is mainly phase change heat exchange, with large local heat exchange. Generally, the cooling and temperature return are relatively fast.There will be a big difference when the heat exchange of exhaust pipe is used in the coolant system.The most intuitive feedback is that the temperature of the cold storage cannot be reached, or the cooling is relatively slow.In fact, it has a great relationship with the arrangement of system exhaust pipe, the pipe form of heat exchange exhaust pipe and the physical parameters of coolant.Glacier coolant through cold storage laboratory tests, different evaporator, different heat exchange pipe, different coolant, different pump circulation system found the following phenomenon.
Under the same heat exchange area, the cooling time of aluminum row tube is longer than that of smooth row tube, and the efficiency of aluminum row tube fin of load coolant system decreases obviously.
Under the same working condition and the same coolant, the cooling time of steel row pipe is close to that of aluminum row pipe. Considering the cost, the economic value of using ordinary seamless steel pipe is better.
The efficiency of the plate heat exchanger is significantly higher than that of the shell and tube heat exchanger. The channel in the shell and tube is several millimeters. The boundary layer of the coolant is relatively small, and the main thermal resistance of the heat exchanger is on the side of the coolant. The reduction of the measured thermal resistance of the coolant significantly improves the efficiency.
According to some comprehensive test data, during the transformation or design of the cold storage, the heat exchange exhaust pipe needs to be reasonably used. First, ensure the flow rate in the exhaust pipe, and then ensure that the cooling in the exhaust pipe is not too large or the single circuit is not too long.
The volume of coolant in the cold storage is small, and the finned tube is used. If it is really needed, the calculated heat exchange area needs to be increased by 30%.In addition, the pressure of the coolant system is generally 2 ~ 3bar. In fact, the pipe used can have less wall thickness and reduce the heat conduction and thermal resistance.
Glacier Coolant focuses on the coolant and provides various application system solutions.
Talking about the refrigeration mode of data center
The data center is part of the future infrastructure. There are more and more data centers in China. Due to the characteristics of high heat load of data center, energy saving of data center has become a hot topic.Especially in the case of carbon peak and double carbon targets, the cooling methods of data center are becoming more and more abundant.This paper mainly analyzes the refrigeration methods and practical conditions of several data centers.
The first is the traditional water-cooled or air-cooled chiller, which is used in most domestic data centers.With the optimization and improvement of the refrigeration system, PUE has reached below 1.4 from more than 2.0 at the beginning.However, due to the high condensation temperature in the south, the efficiency of the refrigeration host is low, so water-cooled units should be used in places with sufficient water resources.
The second is the use of natural cold source combined with traditional refrigeration system. This system is generally used in severe cold areas and cold areas in China.Referring to the application cases of some domestic data centers, the utilization of natural cold energy in such areas accounts for more than half of the time. Half of the extra investment recovery time shall not exceed 4 years, and some areas can recover it in one year.This natural energy recovery system is not standardized, and all data centers are exploring applications.Glacier coolant is specialized in making coolant. It has certain experience in cold energy recycling and can be combined with natural energy utilization in data center.
The third is fluorinated liquid immersion refrigeration, which has been tested in Alibaba data center. They use the boiling point of fluorinated liquid at 50 ℃, phase change refrigeration to cool the CPU, and then reflux through condensation and liquefaction. At present, the test effect is good.The advantage of this method is that the unit heat flux of fluorinated liquid phase change is large, which can meet the fan heat of high heat flux of CPU.In addition, some company use fluorinated liquid as cooling system, which circulates and cools the fluorinated liquid on the basis of immersion. Its heat transfer is between convection and subcooled boiling, and the heat transfer efficiency is also high. This scheme requires a large amount of fluorinated liquid, and the initial investment cost is high.
The fourth is evaporative refrigeration. This system mainly absorbs heat and refrigeration through the evaporation of water vapor without compressor compression. The power load of the system is low, and the PUE can reach 1.1.However, this scheme has a great impact on the weather, and the place with low wet bulb temperature is more appropriate, which is affected by geographical location. In addition, the refrigeration equipment has large volume and high investment.
The fifth is absorption refrigeration, which mainly uses waste heat for refrigeration, but the temperature of the heat source has a great impact on the refrigeration efficiency.The heat source recovered in the data center is at 50 ℃, the efficiency of absorption refrigeration is very low, and it is technically difficult.If there is a waste heat source with a temperature above 90 ℃, this method is still used for energy saving. This refrigeration scheme is rarely used at present. Most scientific research institutions are still exploring absorbing materials and reducing the temperature of recovered heat source.
The sixth is to use direct cooling system for refrigeration. At present, freon is being limited due to double carbon. The transcritical cycle or supercritical cycle of carbon dioxide can be utilized, which needs to be developed with the application of many scholars.
The forms of refrigeration methods are diverse, and the ultimate goal is energy conservation, environmental protection and stability, which is the goal of the data refrigeration system. Glacier coolant focuses on the application of data center and provides professional coolant.
Precautions for Transformation of calcium Chloride Brine Secondary Cooling System
Calcium chloride brine is widely used in practical engineering projects, and its advantages are prominent, such as high specific heat, high density, low viscosity, high thermal conductivity, low cost and so on. However, its disadvantage is also very prominent, that is, it is corrosive. The service life of each brine system will be relatively short. In addition, there will be many small problems within the service life, which requires a lot of manpower to maintain. Therefore, at present, high-end pharmaceutical enterprises no longer use brine and have adopted the corresponding products of glacier coolant.
The new project design institute is designed according to the physical parameters of glacier coolant, with good use effect and low operation cost. However, there are more or less minor defects in the use of the transformation project, and then summarize some precautions for the transformation of brine system:
- During the transformation of the refrigeration host, due to the different physical properties of the coolant, there should be a good trade-off between the cost and effect when selecting the coolant, and try to select the one with similar physical parameters to ensure the heat exchange.
- The transformation of the coolant pump is directly related to the effect of heat exchange. The change of coolant density and viscosity often leads to the cheap operation curve of the pump, which can not reach the design flow, resulting in slow cooling and unable to pull down the temperature. Therefore, in the transformation system, the pump needs to be rechecked and selected. Since the equipment cost of the pump is not high, it is recommended to replace the pump. Variable frequency pump is recommended for systems with long operation time and large load fluctuation.
- It is suggested to adopt the secondary pump circulation system and set a buffer pool in the middle. The larger the filling volume in the pool, the more stable the temperature during operation. However, considering the economy of initial investment, the end load and the frequency of start and stop of the main engine are comprehensively considered. Energy saving and stable operation of the system can be realized.
- For the cleaning of the original system, the calcium chloride in the system must be cleaned. Calcium chloride belongs to strong acid and weak alkali salt. The system is acidic and corrosive.
Glacial coolant has accumulated a lot of experience in the transformation of calcium chloride brine cooling system. The above are some common problems for your design reference, so as to avoid problems with changing the refrigerant directly.
Energy Consumption Control of Coolant System
The application of coolant system has been very common.For example, pharmaceutical chemical industry, refrigeration, HVAC, heat pump and other systems.As the leading enterprise of domestic coolant carrier, glacier coolant has been supplied by more than 2000 enterprises, including new projects and transformation projects. The use effect has been highly praised, but the energy consumption in the use process is different. The owner often mentions the matter of energy consumption. Through our field investigation and analysis, we provide the owner with some opinions on energy conservation and emission reduction.
The first control point is mainly in the design stage. It is necessary to design a matching coolant system according to the physical properties of the refrigerant, so that the coolant pump, refrigeration compressor and end heat exchange can operate at the most efficient point. Such a system is the best for energy saving.This method is only suitable for new projects or projects with complete refrigeration system transformation.
The second control point is the selection of coolant. The design institute has little understanding of the physical properties of coolant. Generally, the physical parameters of ethylene glycol or brine are queried, and the parameters obtained are often insufficient, which will have a certain impact on the calculation.Finally, there will be high energy consumption in the process of operation.The energy consumption of the reconstruction project is generally high, so it is particularly important to select a suitable coolant, which can directly reduce the energy consumption. It is not an exaggeration to say that it is also possible to save 50% energy.
The third control point is the daily operation and maintenance. During the operation process, there are often gases entering the system. The filter or system impurities lead to the increase of system operation energy consumption, which requires regular maintenance.The physical parameters of the coolant need to be tested every year and adjusted in time to ensure the stable and efficient operation of the system.
The operation energy consumption of the coolant system is a whole process control, and each link needs to control the energy consumption.
Under the concept of carbon neutralization, the cooling system also needs fine control.This process requires a close combination of the design unit, the owner and the coolant manufacturer. As a coolant manufacturer, glacier coolant provides cooling system solutions to track the whole process of the project and realize energy conservation and emission reduction of the system.