Pressure Oxygen Increasing System Design Of Oriented To Factory Freshwater Aquaculture

In view of the various aeration devices currently on the market or not suitable for factory breeding oxygenation,or interference with intelligent operation equipment,or the inability to use air as a gas source to solve the emergency oxygenation demand and other issues,this topic takes factory freshwater aquaculture as the application background,proposes the system framework of "pressure aeration",and develops a pressure aeration device for factory freshwater aquaculture.The main contents include:(1)The traditional aeration methods such as aerator,aeration pipe and aeration cone are analyzed.The traditional aeration method is applied to the factory freshwater aquaculture system,and there are mainly the following problems: 1)the traditional aerator cannot carry out operations in the factory breeding pond;2)the bubbles continuously generated by the aeration pipe oxygenation disturb the water body and seriously interfere with the operation of intelligent equipment;3)the oxygen cone can only use oxygen as the gas source,and cannot use air as the gas source to meet the emergency oxygenation demand.(2)Design and trial production of pressure-type aeration device.The pressure-type aeration device is mainly composed of tank components,impeller mixing system,inlet control system,intake control system,etc.,and circulates in the way of "pumping pump water injection-air compressor pressurization-motor driving impeller mixing-flow valve drainage",and each link is independent of each other.On the basis of the design of key components such as tank,stirring device,inlet and drainage system design,and gas path,a prototype of the pressure aeration device was trial-produced,and the control system of the pressure aeration device was designed to complete the coordinated control of water injection,pressurization,agitation,drainage and other links.The maximum pressure tolerance of the tank is 0.60 MPa.The maximum storage capacity of high dissolved oxygen water that can be prepared per batch of prototypes is 385 L.(3)The performance test of the pressure-type aeration device was carried out.The experimental results show that the factors such as impeller speed,stirring time,gas-water volume ratio,and pressure in the tank significantly affect the dissolved oxygen content of the water in the tank(P<0.01).Under the conditions of the test factor level,the impeller speed corresponding to the dissolved oxygen content from high to low is 120 r/min,60r/min,90 r/min,30 r/min,0 r/min,the impeller mixing time is 30 s,20 s,50 s,40 s,10 s,the gas-water volume ratio is 5:5,4:6,3:7,2:8,1:9,and the tank pressure is 0.25 MPa,0.20 MPa,0.15 MPa,0.10 MPa、0.05 MPa。(4)In order to further optimize the process parameters for the preparation of dissolved oxygen,the orthogonal test of the oxygenation effect of the pressure aeration device was carried out with the impeller speed,impeller stirring time,gas-water volume ratio and the pressure in the tank as the test factors.The results showed that the primary and secondary order of the influence of various factors on dissolved oxygen content and dissolved oxygen increases per KW h was pressure,gas-to-water volume ratio,impeller speed,and impeller agitation time.Based on the dissolved oxygen content and the dissolved oxygen increases per KW h,the optimal operating parameters of the pressure-type aeration device selected are: impeller speed 90r/min,impeller stirring time 30 s,gas-water volume ratio 4:6,and tank pressure 0.25 MPa.The dissolved oxygen content of the water prepared under this process condition was 19.94 mg/L,and the dissolved oxygenincreases per KW h was40040.91 mg/(KW?h).(5)In order to verify the oxygenation effect of the pressure aeration device on the fish pond,the fish pond oxygenation test of the pressure aeration device was carried out.The experimental results show that the dissolved oxygen water prepared by the pressure-type aeration device can quickly exchange dissolved oxygen with the pond water body,and the dissolved oxygen in the overall water area can reach equilibrium for a short time,which can meet the emergency oxygenation needs.