Application Of Gas Surface Cleaning In Gas-water Backwash Filter

The survival,life and production of human beings are inseparable from water resources.Although the total amount of water resources in China is large,the per capita water resources are far lower than the world level.Although the total amount of water resources in China is large,the per capita possession is small.The phenomenon of unreasonable use of water resources in China is serious,and the problems of equipment obsolescence,aging and unreasonable use of technology are one of the main reasons.For conventional surface water treatment,filtration generally refers to the process of purifying water by removing suspended impurities through the interception of the filter material layer.With the development of filter technology,backwash technology is also developing.In practical projects,the common v-type filter usually adopts the three-stage washing method,namely,separate air cleaning,then gas-water simultaneous backwashing,and finally separate water washing.In the above process,the small hole at the bottom of the v-shaped groove continues to feed water,and transverse water flow is generated in the filter tank,forming the surface cleaning and pushing the impurities to the central drainage channel.As a result,a large amount of water needs to be raised by the previous structure in the backwash process.Moreover,if the wastewater is not treated properly,the water will not be properly used.This is the deficiency of the existing technology.In order to solve the shortcomings in the operation of the above mentioned filter tank,this paper takes the gas surface cleaning as the innovation point instead of the original water surface cleaning.On the basis of the gas jet theory,through the method of combination of model test and numerical verification,studies are carried out on the jet parameters to achieve the best treatment effect.The main research contents of this paper are as follows:(1)The following studies are made on the theory of gas orifice jet:the general characteristics of turbulent jet,the characteristics of turbulent jet and the study of multiple jets.(2)According to relevant specifications and engineering design experience,the test model was designed and made for experimental study.The analysis of the test results showed that for the trachea with a diameter of 100mm,when the ventilation rate is 15m~3/h,the orifice diameter is 6mm,and the hole spacing is 10cm,the gas surface cleaning effect is the best and the most energy-saving.(3)Based on the results of model test and the theory of gas orifice jet,the experimental results are verified numerically.On the one hand,the reliability of model test results is verified.On the other hand,it provides a reference for the design of process parameters for the gas surface scavenging and water backwashing filter.