It is intended to provide a new way of supplying electricity to the region to address the lack of electricity and electricity in the region.
Qinghai has a vast territory, and most areas have a situation of lack of electricity or even no electricity, which seriously restricts the economic development of the region and the improvement of people's living standards. The solar pool is a salt water pool with a certain concentration gradient. It combines the functions of solar collectors and heat storage devices. It can accumulate solar radiation energy in large areas, large-capacity heat storage and can be operated all day or even across seasons. Solar energy utilization system, after analyzing the resources of Qinghai, the author believes that Qinghai is the most ideal area for developing and utilizing solar pool power generation technology, and believes that it is technically feasible to apply solar pool power generation in Qinghai.
1 Introduction to the Sun Pool The Sun Pool is a facility for collecting and storing solar energy. The ordinary solar pool is a shallow pool with salt, and its depth is generally I! Above, the concentration of the salt solution in the pool gradually increases from the upper layer to the lower layer until it is saturated, and is in a gradient stable state, so that the convection heat can be suppressed, and the bottom of the pool is blackened to absorb the solar energy absorbed by the solar energy T is stored in the lower layer of water. The solar pool can be used for power generation, and the hot water can be extracted for heating, air conditioning, salt making, drying, etc. B. The structure of the practical solar pool is as shown.
2 Factors affecting the construction and operation of solar pools Solar energy resources, salt resources, climate conditions, water conservancy and geological conditions are the main factors affecting the construction and operation of solar pools. The ideal solar pool location should have the following characteristics: a high latitude sun Radiation to improve the performance of the solar pool; b has a large amount of cheap salt and wide ground to reduce the cost; c to have dry and low permeability soil T to maintain its good thermal insulation; d groundwater level to be deep, Reduce the heat loss at the bottom of the solar pool; fresh water should be easily used near e to ensure the cleaning of the pool and pool surface; f wind speed should be small to reduce the surface fluctuation; g evaporation should be small to reduce the water compensation.
However, in the specific construction, the above factors cannot be satisfied at the same time, showing m. The proportion of the four main factors is: 50% of solar energy resources, 30% of salt resources, 6% of environmental temperature and hydropower resources, annual rainfall. According to this ratio, the amount of wind and wind is 4%. According to this ratio, the resources of Qinghai are analyzed and compared. It is believed that the construction of solar pool in Qinghai has a unique advantage.
2.1 Solar energy resources Qinghai Province is located in the northeastern part of the Qinghai-Tibet Plateau. The direct solar radiation intensity is large, the total amount of radiation is long, and the sunshine time is long. The total annual solar radiation in the whole province is between 56377420M/m2, and the average sunshine hours are 2315 ~ 3521h. Among them, it is one of the regions with the most abundant solar radiation resources in China. Among them, the Qaidam Basin is dry and rainless, with more sunny weather. The annual total radiation is above 6700M/m2, and the annual sunshine hours are above 3000h. The total radiation is between 5673-6200M/m2, the sunshine hours are 2315~2700h; the Haibei, Hainan and Huangnan regions are 5900~ The Qaidam Basin in Qinghai Province is one of the key salt lake areas in China, and the Qaidam Basin is now There are 30 salt lakes, including 25 modern salt lakes with surface brines, and 5 dry salt lakes. The salt reserves of the main salt lakes are: stone salt (NaCl) billion tons; potassium potassium 370 million tons; magnesium chloride 2.9 billion tons Lithium chloride 14 million tons. There are currently 18 salt lakes, and the salt mines have been developed and utilized to varying degrees. The total output of products and primary processed products obtained from salt lake resources development is about 1.5 million tons, of which the main products
2.3 Freshwater resources The water resources of the province's surface water resources are divided into four major river systems, namely the Yellow River, the Yangtze River, the Lancang River and the Inland River. The rivers with a catchment area of ​​more than 500Km2 have 276 rivers. The average annual runoff of the province is 62.2 billion m3, the province of Qinghai. The total amount of water resources is 63.674 billion m3, the comprehensive recharge of groundwater in the plain area of ​​the province is 6.315 billion m3, and the shallow groundwater runoff is 3.377 billion m3. The fresh water resources are abundant.
2.4 climatic characteristics The province's climate belongs to the typical plateau continental climate, dry, windy, cold, and oxygen-deficient. The annual average temperature of the province is -5.6T-8.6. Due to the large terrain and relative enthalpy, the temperature distribution in the area as shown in the attached table is formed.
Scheduled gas distribution in Qinghai Province The average temperature in the sea area is the Yellow River and the Qinshui Valley sub-warm area. The Qaidam Basin, the sub-cold area of ​​the Qaidam Basin, and the Qinglian-Yuanyuan-2 cold area, the Qilian Mountain area and the Wudaoliang area are generally When the annual average temperature is lower than Ot: the solar pool should not be built. When the temperature is lower than -5TC, the solar pool cannot be built.
The general trend of precipitation and evaporation in our province is that the evaporation is greater than the precipitation and meets the requirements of the solar pool. However, if the difference between the two is too large, it will affect the solar pool. The annual average of the Qaidam Basin in our province. The evaporation is above 3000mm, which is much larger than the precipitation, which needs to be supplemented by sufficient fresh water resources.
The province's average wind speed is less than 3m / s, accounting for 35.8%, the sun pool is suitable for construction in areas with low wind speed, otherwise it will increase wind protection measures. The wind speed is above 5m/s. In principle, it is not suitable to build a solar pool. For example, the cliffs in our province are all above 5m/s.
3.1 Solar cell power generation principle Principle of solar cell power generation system The working principle of solar cell power generation is to use the 篼 warm concentrated salt solution to evaporate the low boiling point medium in the evaporator, and the generated steam drives the steam turbine and drives the generator to generate electricity. The vapor discharged from the steam turbine enters the condenser and is condensed. The condensate is pumped back to the evaporator by a circulation pump, and the hot salt solution heated by the solar pool is evaporated to start a new cycle. see.
3.2 Construction of the solar pool 3.2.1 Solar pool area The empirical formula for calculating the solar pool area was derived abroad. , I.lTd+ 1 plant solar pool storage area received radiation; (W / m2; Ip = 0.31If) I - annual average total radiation; (W / m2) b reflection loss correction factor, related to latitude; L year Average load. (W) 3.2.2 Sun pool depth and pool wall slope The solar pool storage area used for power generation should not be too deep, about lm, the gradient area is about 1.5m, the surface area is 0.3m, and then the freeboard (not wet water) Partially) 1.01, the total pool depth of this Yangyang pool is about 4m; at the same time, in order to prevent soil movement and collapse at the top of the pool wall, the pool wall should be formed into a slope shape, and when the disturbance of the wind is large, a slope ratio of 1:1 can be adopted.
3.2.3 lining in order to prevent the heat of the solar salt pool from being taken away by the soil and the groundwater below and the salt solution is lost to pollute the environment, the wall of the pool and the bottom of the pool should be used at home and abroad, and the effect is better. Type liner (sandwich type), which is made by overlapping clay and film. This type of liner has relatively low requirements on film materials, and is suitable for use in Qinghai, where the economy is relatively backward. The film can be made of tantalum density polyethylene. (HDPE) and polyethylene (PVC), etc., can be designed as three layers of 10cm poor clay sandwich two layers of film.
3.3 Establishment of the solar pool gradient The solar pool gradient means that the concentration of the salt solution in the pool gradually increases from the upper layer to the lower layer until it is saturated, and is in a gradient stable state. The establishment of the gradient requires a water pump and a diffuser. The number and type of pumps can be determined according to the volume of the solar pool. The diffuser can be made by itself. It consists of two plates supported by several spacers. Water comes in from the middle of the diffuser. And diffuse out from the horizontal direction between the two plates, so that the water can be mixed with the brine and greatly reduce the diffusion speed in the vertical direction, thereby avoiding local diffusion, and the number of diffusers should be consistent with the water pump.
3.4 The extraction and heating process of the solar pool is to raise the concentrated salt solution with high temperature from the storage area, and then return the cooled concentrated salt solution to the storage area after heat exchange. Heating is very important for maintaining the gradient, and heating is also a key part of power generation. The heat-raising equipment is mainly a pump and a pipeline for conveying salt solution. The pipeline must be corrosion-resistant, high-strength and anti-aging, such as high-temperature polyethylene pipes.
Through the above process, coupled with power generation equipment such as steam turbines, generators, evaporators, condenser organic media (low boiling point media), power generation control equipment and transmission lines, the solar pool can theoretically generate electricity, but there are still some technologies. The problem remains to be studied. 4 Problems and suggestions Although the solar pool power generation technology has been developed into a practical stage abroad, such as Israel has built a test solar pool power generation system with a capacity of several hundred kilowatts, but my country is still blank, therefore, There are still some technical problems in the development and utilization of solar pool power generation technology in Qinghai.
4.1 Pool surface anti-icing technology Qinghai Province is located in the cold region. The annual average temperature is -5.6-8.6T. Due to the cold weather, the surface of the solar pool is frozen. When the ice layer is too thick, it will hinder the transmission of solar radiation and affect the performance of the solar pool.
4.2 Pool surface wind protection technology The average wind speed in most areas of Qinghai is more than 3m/s, and the frequency of high winds is also high. Strong winds easily disturb the non-troposphere of the solar pool, causing the entire solar pool to fail, so wind protection measures must be considered in Qinghai.
4,3 Other solar cell gradient maintenance and transparency maintenance technology has no mature application experience in China at present; in addition, due to the high corrosivity of high temperature concentrated brine, many equipments and devices must resist corrosion and are therefore more expensive; If there is leakage in the solar pool, it will cause environmental pollution. Therefore, the author suggests that the relevant departments set up a project as soon as possible to establish a demonstration 150 kW solar pool power station in the Qaidam Basin of Qinghai to supply electricity to small manufacturers and prepare for the large-scale promotion of the solar pool in the region. It would be even better if you can apply for international assistance.
The anti-theft Wheel Nut & Bolt Kits are more and more popular now which are also known as an anti disassembly screw, which is used for preventing the theft of a vehicle which park in an outdoor public place. This kind of screws need to use special tools to take out, play the role of anti-theft. It's expensive to buy the alloy wheels, but it's economic to buy the Wheel Nut&Bolt Kits. So it's worthy of buying one set of Wheel Nut&Bolt Kits to protect your alloy wheels from stealing.
The Wheel Nut & Bolt Kits have many different types. It's easier to buy the Wheel Nut&Bolt Kits, instead of just buying a separate nut or bolt.
Lug Nut Lock Set,Locking Lug Nut Set,Wheel Nut Set,Wheel Lock Replacement
Ningbo Best Way Auto Accessory Co., Ltd. , https://www.autoaccessorycn.com