Development trend and application of energy-saving

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Analysis on the development trend and application ways of water pump energy-saving technology

in thermal power plants, the auxiliary power accounts for about 8% - 10% of the total power generation, and the power consumption of pumps and fans accounts for about 70% - 80% of the auxiliary power. Therefore, reducing the power consumption of pumps and fans plays a great role in improving the economic benefits of power plants. The power consumption of circulating water pump is related to season and load. The frequency conversion transformation can not only ensure its effective work, but also ensure its minimum power consumption in low load and different seasons. It is flexible to use and has obvious energy-saving effect

I. the development trend of water pump energy-saving technology in China

at present, vector controlled frequency converters have been widely used in the stepless speed regulation of AC motors in general machinery, textile, printing and dyeing, papermaking, steel rolling, chemical and other industries in many electric drive occasions at home and abroad, which has obviously achieved energy-saving effects and met the requirements of process and automatic speed regulation. However, it has not been fully applied in the application field of fans and pumps. The main reason is that there is not enough understanding of the large amount of energy saving of fan and water pump loads. Therefore, we will introduce the energy-saving principle and application status of fans and pumps to customers. The power consumption of fans and pumps in China accounts for more than 60% of industrial power consumption. If we can make full use of frequency converters in this field for variable frequency stepless speed regulation, it is a strategy for our country, which is seriously short of power in developing processing and manufacturing industry. Fan is a gas transmission device. A water pump is a device that transmits water or other liquids. In terms of its structure and working principle, the two are basically the same. Now take the fan as an example. Natural ventilation cooling tower, circulating water pump, circulating water pipeline and pipeline accessories are important components of the circulating water system of the power plant. It is of positive significance to study the system scheme and determine the optimal system configuration in the preliminary design of the power plant to reduce the construction cost of the project. The core part of the design of circulating water system is the reasonable selection and configuration of natural ventilation cooling tower and circulating water pump. In the construction of circulating water system, their investment cost is the most, the construction is the most complex, and they have the greatest impact on the total investment of power plant. It directly affects the unit cost of power engineering construction and the payback period of power plant investment. The optimal design of water supply system is the basis of system scheme selection, and the annual cost of circulating water pump motor has the greatest impact on the scheme design. Under the premise of ensuring the safe operation of steam turbine and full load power generation, how to reduce the annual cost of motor is worth thinking by every engineering designer

II. Problems in the use of water pumps

1. The design technology of water pumps themselves is not high

at this stage, China's water pump design mainly follows the traditional model conversion method and speed coefficient method. These design methods are outdated to some extent, because they are based on the old experience of water pump design, and cannot exceed the past design level in the design process, and cannot make a breakthrough in efficiency improvement. In addition, the fund and personnel investment of the pump design unit in technology are selected according to our needs, and the curves of load deformation, load time, load displacement, displacement time, deformation time and experimental data are printed; The lack of innovation motivation and awareness of pump designers leads to the lack of a qualitative improvement in the technical content of pump products, the inability to improve the technical content of the pump itself, and the failure to do energy conservation work. In addition, the pump manufacturing enterprises unilaterally focus on economic benefits and ignore the energy-saving work of pumps. The state also has no policy support and financial incentives in this regard, resulting in the pump manufacturing enterprises' lack of enthusiasm for pump energy conservation and improving pump efficiency

for example, 4 Chuan 2. There are misunderstandings in water pump energy conservation.

our understanding of water pump energy conservation in the past was mainly to improve the efficiency indicators of water pumps. In fact, this is a misunderstanding of water pump energy conservation, which is a one-sided understanding. The energy-saving range we mentioned is not only an efficiency index, but also includes the stability of the performance of the water pump, the service life of the water pump, the saving of materials and other factors. Then, as for the specific use environment of the water pump, we should also carry out targeted energy-saving design, such as the sealing performance of the water pump, the hydraulic performance of the water pump, the high temperature resistance of the water pump, etc., which should be designed for different environments and different uses. Therefore, the energy-saving research of water pump is a very complex work. Our understanding of the concept of energy-saving should not be too one-sided, but a comprehensive and overall understanding

3. Factors of users and individuals

when purchasing pumps, users and everyone often pay attention to whether the pumps meet their own needs and whether the price is relatively cheap, but they don't pay much attention to the energy-saving technical indicators of pumps. This demand of consumers also discouraged the enthusiasm of pump design and manufacturing units to carry out energy-saving technological innovation. Moreover, when choosing pumps, a large number of consumers should choose pumps with excessive flow and head margin to ensure that they can meet their own use needs. Such consequences directly lead to the fact that the actual operation efficiency of the pumps in the process of use is far lower than the maximum efficiency of the pumps, and they can't operate in the high-efficiency area all the time. In addition, in the process of use, because the management and inspection of the user unit are not strict, the operation and maintenance are not appropriate, and the maintenance is not timely, the water pump often breaks down in the process of use, resulting in a lot of energy waste

III. energy saving technology of water pump

1. Energy saving of water pump itself

in the process of designing and manufacturing water pump, the design and manufacturing personnel should have energy-saving consciousness in their minds. As the design and manufacturing unit of water pump, they have the ability to provide efficient and energy-saving water pump products to the majority of consumers. The design unit of the water pump should select excellent hydraulic models and study scientific and efficient hydraulic design methods when designing. In the design process, the reliability test of the water pump and the material selection test of the product should be carried out, so as to improve the service efficiency of the water pump products. Pump manufacturers should formulate their own enterprise standards higher than the national machinery standards in the manufacturing process, and try every means to reduce hydraulic losses. During the manufacturing process, each process shall be strictly controlled to minimize the roughness of the flow passage parts, carefully handle the gap and appropriately reduce the gap value, so as to improve the service efficiency of the water pump and achieve the purpose of energy saving of the water pump

2. Improve the energy saving of the water pump system

in addition to paying attention to the energy saving of the water pump products, we should also pay attention to the development and research of the energy-saving technology of the whole system. The use efficiency of the water pump also has a great relationship with the related supporting facilities. The energy-saving technology of the system is even more important than the energy-saving technology of the water pump itself. The research on energy-saving technology of the system should focus on carrying out system engineering design from the perspective of energy conservation, so that each link of the system can achieve the best matching effect. In the operation process of the water pump, the whole water pump system can give full play to its maximum efficiency. In this regard, it mainly includes the connection of water pump and motor, the design of pipe, the connection and coordination of relevant accessories, so that they can play their maximum role, so as to improve the service efficiency and service life of the water pump system

3. Energy saving in water pump operation

the efficiency of the water pump itself has been improved, and the whole water pump system has also been designed to save energy, but this is only one aspect, and there is also a very important aspect in the operation of the water pump. In practice, due to the improper use of the water pump, the water pump can not play its role efficiently. In addition, the use environment of the water pump is very complex, and different environments require different process flows and process parameters. These aspects should be adjusted flexibly in the process of use. For example, when adjusting the water pump system, we should pay attention to reduce the loss of energy as much as possible, and use less throttling adjustment methods. We can solve the problem from the angles of angle change, speed change, turning, etc., so as to ensure that the motor and water can work efficiently if they are only coated with antirust oil. When installing the water pump oyster, adjust the angle of the consuming impeller according to the needs of the specific use environment to adjust the angle, and reasonably determine the blade installation angle, so that the water pump can work efficiently. Turning adjustment refers to the adjustment of the pump performance by turning the impeller diameter, which is the simplest and most important energy-saving measure. In turning adjustment, there is a common sense that the flow, head and shaft power before and after turning the impeller are proportional to the impeller diameter, direct diameter square and diameter cubic before and after turning. One of the problems that should be paid attention to when using turning adjustment is that the adjustment should be carried out within a safe range, rather than unlimited adjustment. Variable speed regulation is the most direct and commonly used regulation method in daily use. It will not produce power loss, but directly change the performance of the water pump through the change of the speed of the water pump. In daily life, the main ways of realization are through gear box, belt drive, frequency conversion, motor and so on. Among these ways, the most ideal way is variable frequency speed regulation, which has the advantages of high efficiency, stepless speed regulation and wide speed regulation range, but its disadvantage in application is high investment

4. Energy saving of users and individuals in the use of water pumps

in the specific use environment, a reasonable water pump system is selected. In the process of operation and use, users and individuals should also pay attention to establish energy-saving awareness and carry out strict management, so that the water pump can realize energy saving in the process of operation. At the same time, the water pump system should be maintained frequently in the process of operation, so that the water pump system can be in the best running state, and the problems existing in the water pump system can be found through ordinary maintenance, which can not only prolong the service life of the water pump system, but also receive good energy-saving benefits

with the development of modern technology, some new design methods, advanced casting and processing techniques have also been applied in production, which have greatly improved the efficiency of water pumps and promoted the development of energy conservation. With the improvement of people's consciousness and the progress of technology, we believe that these problems existing in the current energy-saving work of water pumps must be solved. The prospect of energy-saving work of water pumps is very good, so remember to eliminate the initial force and then clamp the extensometer

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