| River water source heat pump(RWSHP) is a new type of building energy-saving technology. Now it is got more and more attention in Chongqing and even the country. Because the sediment concentration of the Yangtze River and Jialing River is high and the sand diameter is getting smaller as the Three Gorges Reservoir Area finished its water storage work, how to get the best possible cost-effective water has become the key technical issue to apply river water source heat pump in Chongqing, and has important impacts on the construction of the entire system, operating costs and energy efficiency. So it is urgent to conduct a further research on water intake works.According to the raw water quality from the Yangtze River and Jialing River, we developed the lateral flow vane inclined plate water intake head(LFVIPWIH) and studied on the inffluent, sand removal and sand discharge of the water intake head based on the research progress at home and abroad.And we obtained the following main results:①They analysed the hydrology, sediment concentration and temperature of the Yangtze River and Jialing River, and found that the tow rivers were appropriate to implement the open-style River water source heat pump technology.But the high sediment concentration of theYangtze River and Jialing river water and small particle size of the sand from June to September limited application of the RWSHP. So the technologies of the water intake and water treatment have strict requirements.②They developed the LFVIPWIH, and carried out the experiments on sand removal efficiency with coarse sand, fine sand, mixed sand when the flow rate was in the section level of 7mm/s~15mm/s range, respectively. Also we obtained that the main factors to affect the sand removal efficiency of the lateral flow vane inclined plate are as follows: section level flow(empty tower velocity), the structure size of vane inclined plate, the obliquity of vane inclined plate, the vane cell number. The experiments showed that it was suitable to select the device for sand removal with lateral flow vane inclined plate with the specs of vane inclined plate in 60mm×60mm×30mm, 60°-obliquity of the vane inclined plate, 9mm/s~15mm/s of the section level flow, and 25 grids of the vane cell.③They proposed the way of inffluent with wavy weed preventation, anti-blocking and bucket self-cleaning sand discharging. Also we identified the flow velocity and size of the water inlet of the wavy water intake. In the same time, we obtained the reasonable range of main design parameters, such as the total volume and height of the sand bucket set, the total area of sand discharge hole and height of the sand discharge tube, etc.④On the basis of the above research, whlie the scale of water intake quantity was 5.0m3/h, the sediment concentration of the raw water is 0.5~3.0kg/m3,the sediment median diameter D50 is about 12μm and the velocity of section level flow changes between 9~15mm/s, we carried out the pilot studies on sand removal efficiency, effluent turbidity, sediment diameter of effluent of the LFVIPWIH. The results show that: The LFVIPWIH has a good effect on sediment removal which was more than 45%, but has nothing to do with turbidity. Compared with the raw water, the sediment median diameter D50 of the effluent decreased significantly. D50 is basically under 10μm, and the Dmax of effluent is about 74.17μm. It is worth noting that the LFVIPWIH is useless for the raw water while the sediment median diameter is under 5μm. Compared with the existing water intake head of weed preventation and sand removal on the performance of separation and economic, LFVIPWIH has significant technical and economical advantages. It is feasible to apply the LFVIPWIH in the surface water source heat pump water system of the upper reaches of the Yangtze River.The results of this research will also provide a reference for the similar problems which encountered in the upstream area of Yangtze River.
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