Sludge dewatering technology

Pressure filtration dehydration section

The press and filter dehydration section mainly includes support and protective cover, transmission device, tensioning device, rectifying device, detection and protection device, filter belt washing device, series press and guide roller and filter cake unloading device.

(1) Bracket

The bracket of press filter section is used to support other components of pressure filter section to play the role of positioning and supporting. The bracket is made of section steel with sufficient stiffness to produce vibration without bending deformation and operation under all dynamic and static loads. The frame is convenient for observation and maintenance of internal parts.

(2) Drive device

The driving device is composed of reducer, transmission roller and so on, with overload and overheating protection function. The reducer drives the driving roller of the upper filter belt to rotate, and drives the driving roller of the lower filter belt through a pair of gears with the same modulus and number of teeth to ensure the synchronous operation of the upper and lower filter belt. The motor is squirrel-cage asynchronous motor. At the same time, the stepless speed regulation can be realized by the frequency conversion governor, which can make the upper and lower filtration with a speed range of 0.4-5m/min, in order to adapt to the filtration requirements of different situations, and the system indication is consistent with the actual mechanical speed.

The output speed is adjustable, all moving parts run smoothly without abnormal phenomenon, and the noise is no more than 80Db(A). The protection grade of the motor is IP54, grade F insulation, and the power supply is applicable to 3P/380V/50Hz.

(3) Tensioning device

The function of the strainer tensioning device is to tensify the upper and lower strainer to avoid the slipping of the strainer and roller, and to dehydrate the filter cake by applying certain pressure. This device adopts air pressure tensioning, one cylinder is set at both ends of the roller, the four cylinders tensioned by the upper and lower filter belt are controlled by the air control valve, and a mechanical synchronous mechanism is set to ensure synchronous action.

(4) Rectifying device

The device adopts one side of the cylinder to correct deviation, and its structure and principle are the same as that of the concentration section.

(5) Detection and protection device

In case the rectifying device fails and the one-side deviation of the filter belt reaches 40mm, the proximity switch of detection protection will send a signal to stop the system. Two emergency stop buttons are set on both sides of the machine for emergency stop.

(6) Filter belt washing device

The filter belt washing device is equipped with an equispaced nozzle to spray water in a fan shape across the width of the press cloth, which is conducive to reducing water pressure loss and good regeneration of the press cloth.

(7) Series press roller and guide roller

The structure of each roller is similar. The driving roller and the rectifying roller are covered with neoprene to increase friction. The two main dewatering rollers are steel filter drums, the rest of the roller surface are covered with a special anticorrosive coating, so it has a strong corrosion resistance.

(8) Filter cake discharging device

The upper and lower active rollers are equipped with upper and lower unloading devices. The blade of the scraper is pressed on the roller along the tangent direction of the diameter of the unloading roller, and its tightness can be adjusted to an appropriate degree.

(9) Filter belt

The filter belt is a closed dewatering mesh belt made of 100% polyester monofilament according to the required wire diameter and braided. It has the advantages of high strength, smooth surface, good permeability, not easily blocked, high solid recovery and long service life. The service life of the filter belt conforms to the relevant national industrial standards.

(10) Bearing

All bearings are outer spherical centering bearings, lubricated with grease, and protected by sealing plate and dust cover. The service life of all bearings is not less than 10000 hours.

(11) Machine automatic protection device

In order to ensure the normal and continuous operation of the machine and the automatic stop in case of serious failure, it is required to set up the necessary automatic protection devices:

A. The deviation rectifying device of the filter belt fails, and the deviation of the filter belt exceeds the allowable range (40mm on the left and 40mm on the right), then the machine will be given an alarm and shut down.

B. Two emergency stop buttons are set on both sides of the machine to be used for stopping in an emergency.

(12) Pneumatic control cabinet

The air compressor provides the power needed for cylinder tensioning and cylinder rectifying. Select the appropriate control pressure, can achieve the best effect, in the pneumatic control cabinet on the door panel set tensioning barometer and pressure adjustment knob, rectifying air pressure by the air control triplet display and adjustment.