Research And Design Of Sludge Organic Sand Wash System For Urban Drainage Network Ditch

As one of the key parts of the Internet+ Urban Drainage Netcom Ditch Sludge Mobile Treatment and Disposal Project,this article's urban drainage pipe Net Trench Sludge Mobile Disposal Device can realize the mobile resource of the sewage sludge and convenient handling through the Internet.In this paper,the sludge cleaning process in the urban drainage ditch net-groove sludge disposal device was studied,and a number of advanced and mature technical principles were used to design an automatic sludge-grading organic sand and gravel washing device system.The aim is to reduce the content of organic matters in the sludge so as to obtain high-purity sand and gravel in the subsequent process,which can be applied to low-grade building materials(road foundation materials,pipeline landfill materials,etc.),so that the sludge can be used for resources and the pipeline plugging which other environmental pollution problems caused can be solved.In response to the call of the nation to build smart cities and sponge cities,we have built the most beautiful homes for human settlements.(1)Coanda effect to achieve initial separation of siltThe organic sand and sand washer is the main device of the organic sand and stone washing system,design concept comes from a spoon,the water will be bent along the direction of spoon deflection,changing the original direction of operation.Therefore,the design of a turbo bell mouth,water,sand,organic and other components of the mixture by this device,the direction of its movement from the original vertical to horizontal direction.And the mixed material has a very high flow rate in the feed zone and its flow rate decreases rapidly when it changes to a horizontal direction.Therefore,the mixing material in the direction of the swirling flow and run down the dual role of flow rate,to achieve the initial separation of mixed materials.(2)The fluidized sand bed is used for laminar washingAccording to the liquid-solid fluidized bed coarse coal slurry separation mechanism,a fluidized sand bed sand washing device was designed.Separation of sand and sand in the lower part of the sand washing device can achieve stratification of organic matter and minerals.The density of the mixed material is lower than that of the fluidized sand bed,and the rising water flow enters the overflowing weir of the sand washing device.This part is intermittently discharged through the ball valve to obtain the product fine sand and the organic floating material contained therein.If the density of the mixed material is higher than the density of the fluidized sand bed,it will enter the conical sand discharging device through the center sand discharging port through the fluid distributor.And with the screw conveyor discharge,to get the product coarse sand.At the same time,there are three layers of stirring devices inside,fluidized sand bed can increase the residence time of mixture materials in the device body,and achieve effective washing of sand and gravel.(3)Ultrasonic cleaning to promote the effect of sediment washingUltrasonic cleaning can increase the floatability of minerals;speed up the flotation rate;increase recovery;improve selectivity.At the same time,ultrasound on the minerals are broken,cleaning and flocculation.Larger particles can produce crushing dissociation and surface cleaning effect.In this system,a special design spiral ultrasonic cleaning device is used for secondary washing of fine sand.Spiral sorting can not only achieve the separation of organic floating material and fine sand,but also increase the time of ultrasonic cleaning,so that the fine sand washing effect can be more effective;at the same time,in the main scrubbing device of coarse sand,the internal three layers of the device can be agitated,so that the muddy sand surface material can be effectively dropped off,thereby enhancing the washing effect and achieving flushing.After the organic content <5%.(4)Spiral conveying enhances dewatering performance of siltScrew conveyor is the last of the dehydration process of the system,then sent to the outside of the device,while dehydration and transportation,is one of the key equipment in particular.Sand washing device to wash the organic matter in accordance with the process,automatic but not continuous discharge,so as to ensure the device separation and cleaning efficiency,the solid content of 90%.(5)Automatic control system to meet the device intelligent operationAutomatic control system is the main system of the device,its main role is to monitor the critical value of the system in real time and control their normal work is a very important part.Among them,the pressure sensor signal through the PLC control system will convert the data into an average density,and then through a PLC internal PID control loop.The PID control process compares the sensor measurements with user setpoints and the actuator controls the auger to turn it on or off to control the entire system to maintain the required suspended bed density.(6)Multi-layer products to achieve secondary use of resourcesBefore the sand washing device before a vibration screening process.Vibrating sieve 10 mm above the branches,garbage and other large particles with the municipal garbage truck away disposal;under the sand washing device is divided into two layers: the upper overflow fine sand and organic floating debris by spiral sorting ultrasound device,filtered to remove Out of the organic matter,to obtain a diameter of less than 0.2mm fine sand;the lower fluidized sand bed,mechanical stirring and ultrasonic cleaning equipment,and the screw conveyor dehydrated gravel can be used as low-grade building materials(road base material,pipe Landfill materials,etc.).