Method for adjusting ore slurry liquid level and foam thickness of coal flotation machine

[0021] At present, the liquid level sensor not only has a wide range of varieties, but also has greatly improved detection accuracy, which provides great convenience for slurry level detection. The thickness of the foam can be tested according to the conductivity of the foam layer. The testing equipment has a wide range of options, and the actuator technology has also been rapidly developed. The invention combines the controller 8, the actuator (the dosing amount regulating valve 3 and the gate height adjustment device 6), the liquid level sensor 4, and the electrode foam thickness sensor 1 to intelligently detect the slurry level and foam thickness And adjustment, and achieved satisfactory results.

[0022] The level sensor 4 is a pressure type level gauge, a float level gauge, an electronic ruler level gauge, an ultrasonic level gauge, a laser ranging level gauge, a radar level gauge or a magnetostrictive level gauge, which can be based on actual conditions. Select the situation. The foam thickness sensor 1 can choose high-resistance, low-resistance, and ultra-low-resistance models according to the different conductivity of the flotation foam. The gate height adjusting device 6 is an electric actuator composed of a motor, a reducer, and a rack and pinion mechanism. An electro-hydraulic actuator or a pneumatic actuator can also be used, which can be selected according to actual conditions.

[0023] The present invention includes the following steps:

[0024] (1) Determine the setting value H of the slurry level of the flotation machine tank according to the nature of the incoming slurry sp And set the dead zone interval ±X, and determine the lower limit of foam thickness H according to the specific production situation l And the upper limit of foam thickness H h , And write them to the controller 8;

[0025] (2) Install the liquid level sensor 4 in the flotation cell, and install the foam thickness sensor 1 (electrode liquid level switch) above the flotation machine cell body, and its common electrode 1-1 extends into the slurry layer to realize the electrode Reliably ground, adjust the height of the lower end of the low electrode 1-2 of the foam thickness sensor 1 to H sp +H l , The height of the lower end of the high electrode 1-3 is adjusted to H sp +H h , The slurry level height signal (digital or analog) detected by the liquid level sensor 4 is transmitted to the controller 8 (programmable controller) through the signal cable as the current value H of the slurry level height cv.

[0026] (3) Adjustment of slurry level height:

[0027] The controller calculates the setting value H of the slurry level height sp And the current value of the slurry level height H cv The difference ΔH = H sp -H cv , If ΔH>+X, the controller outputs the control signal of the gate height adjustment device, so that the gate height adjustment device drives the tailings gate up by one step, reducing the slurry flow into the tailings to increase the slurry level until ΔH falls within the set dead zone interval ±X; if -X≤ΔH≤+X, the controller does not output the control signal of the gate height adjustment device, and the gate height remains unchanged; if ΔH is less than -X, control The controller outputs the control signal of the gate height adjustment device, so that the gate height adjustment device drives the tailings gate down by one step, and increases the slurry flow into the tailings to reduce the slurry level until ΔH falls within the set dead zone ± X, so as to keep the slurry level near the set value;

[0028] (4) Adjustment of foam layer thickness:

[0029] Adjust the slurry level to the set value H sp Later, if the foam layer does not reach the lower end of the lower electrode 1-2, the foam thickness sensor 1 has no corresponding signal output, indicating that the foam layer thickness is less than H sp +H l -H sp =H l , Which is less than the lower limit of foam thickness, which is not conducive to the scraping of the concentrate scraper. At this time, the controller outputs the control signal of the dosing amount regulating valve on the dosing pipe to increase the opening of the dosing amount regulating valve by a certain value , Increase the foam thickness; if the foam layer reaches the lower end of the low electrode 1-2 but not the lower end of the high electrode 1-3, the foam layer thickness is greater than or equal to the lower limit of the foam thickness H l And less than the upper limit of foam thickness H h At this time, keep the opening degree of the current dosing amount regulating valve 3 to ensure normal production; if the foam layer reaches the position of the lower end of the high electrode 1-3, the thickness of the foam layer is greater than or equal to H sp +H h -H sp =H h , That is, it is greater than or equal to the upper limit of the foam thickness, the amount of foaming agent is too large, the foam is unstable, and the concentrate product cannot be carried well. At this time, the controller automatically reduces the opening of the dosage control valve to reduce the thickness of the foam layer , The foam thickness will be controlled within the set range.

[0030] The invention uses electromechanical integrated equipment to intelligently adjust the slurry level and foam layer thickness of the flotation machine in real time, and can control the slurry level and the thickness of the flotation foam layer within a reasonable range required by the flotation production process , To ensure that the clean coal can be separated out with high efficiency, improve the concentrate yield and product qualification rate.

[0031] This method is a brand-new method for detecting and adjusting the slurry level and foam layer thickness of the cell body of a coal flotation machine, and has high promotion value.