RU2813638C1 - Dust flushing device - Google Patents

Abstract

FIELD: dust collection technique.

SUBSTANCE: invention relates to devices for unloading dust from dust collecting equipment bins at industrial enterprises in power engineering, metallurgy and other industries. Device comprises a housing with opening and welded covers and with a cylindrical part in the form of an air chamber, at the top of which there is a dust inlet, and at the bottom there is a slit for outlet of the hydraulic mixture. On the opposite side of the housing relative to the cylindrical part for supplying flushing water to the slit for the hydraulic mixture outlet, a supply branch pipe with a nozzle and a hatch for servicing the nozzle are installed. A drain pipe is installed opposite the slit for the hydraulic mixture outlet. Screen to prevent emission of dry dust is installed with possibility of overlapping slit for output of hydraulic mixture by 25–60 %. Additional air chamber is located above cylindrical part of housing. Additional supply branch pipe for supply of flushing water and additional hatch for maintenance of the nozzle are located in the lower cylindrical part of the housing diagonally to the first supply branch pipe with a nozzle. Dust inlet is inclined with angle of inclination to horizontal equal to 50–80°. Cylindrical part of housing, including additional air chamber, is made with height H 1,000–2,000 mm and diameter D 400–1,200 mm.

EFFECT: higher reliability in conditions of high dust load due to reduced speed of dust at the input of cylindrical part, prevention of ejection of dry dust and effective washing of pulp.

1 cl, 4 dwg

Description

The invention relates to a dust washing device and is widely used as a device for unloading dust from bins of dust collection equipment at industrial enterprises in the energy sector, metallurgy and other industries.

A device is known for hydraulically unloading dust from the hoppers of a gas treatment plant, for example an electric precipitator. The installation consists of fields in which solid particles are separated from gases, and bunkers into which the collected dust is poured. The outlet of each bin is equipped with a device for unloading dust with a water supply and removal of a mixture of dust and water (pulp). (GB 2055629 A, B03C 3/88, 03/11/1981).

The closest analogue of a dust-removing device is an ash-removal device, which is both a water seal, since the dust-collecting installation operates under vacuum, and a device for unloading the collected dust from the hopper. The overall reliability of the entire dust collection installation, the flow rate of flush water, as well as the service life of the collecting electrodes and shaking systems depend on the reliability of the operation of such devices. The design of the ash flushing apparatus is disclosed in OST 24.838.16-74. Change No. 4. Ash flushing devices. Basic parameters and dimensions.

Technical requirements.

The principle of operation is that water constantly flows into the device through the inlet pipe, which fills it to the upper level of the drain pipe. In operating condition, the water level in the cylindrical part is higher than the level of the drain pipe by the amount of vacuum in the ash collection unit, which, as a rule, is in the range of 50-300 mm of water. Art. Dust enters through the ash flow, which, together with water, forms a hydraulic mixture (pulp). Through a slot at the bottom of the cylindrical part of the body, the pulp is washed out and enters the drain pipe, and then into the hydraulic ash removal channel. The design of these devices was developed for installation under the bunkers of ash collection plants about 50 years ago, when, for example, periodic shaking of the collecting electrodes, which allows for more efficient collection of solid particles, was not widely used for electric precipitators. In addition, highly efficient bag filters have begun to appear at domestic stations, which also require ash flushing devices designed to unload large amounts of dust.

The disadvantages of this design include unsatisfactory operation under conditions of high dust load, which leads to clogging of the housing and drain pipe with dust, dust emissions from the apparatus, the need to increase the water pressure in the supply pipe and, accordingly, increase the flow of flush water to ensure unloading, increase the frequency regeneration of collecting electrodes or sleeves to reduce the peak dust load on the device, etc. The release of dust from the ash flushing apparatus is also associated with the “piston” effect, when a large volume of dust, entering the hopper, moves along the vertical ash chute to the ash flushing apparatus. The higher the ash estrus, the more pronounced this effect is.

The technical problem to be solved by the claimed invention is the development of a new design of a dust-washing device that reduces or eliminates the above-mentioned disadvantages.

The technical result of the claimed invention is to increase the reliability of the device under conditions of high dust load by reducing the speed of dust at the entrance to the cylindrical part, preventing the emission of dry dust and effectively washing out the pulp.

The technical result of the claimed invention is achieved by the fact that a dust-flushing device containing a housing with an opening and welded lid and a cylindrical part in the form of an air chamber, at the top of which there is a dust input, and at the bottom - a slot for the outlet of the hydraulic mixture, on the opposite side of the housing relative to the cylindrical part to supply flush water to the slot for the outlet of the hydraulic mixture, a supply pipe with a nozzle and a hatch for servicing the nozzle are installed; a drain pipe is installed opposite the slot for the outlet of the hydraulic mixture, contains a screen to prevent the emission of dry dust, installed with the possibility of closing the gap for the outlet of the hydraulic mixture by 25-60%, an additional air chamber located above the cylindrical part of the body, an additional inlet pipe for supplying flush water and an additional hatch for servicing the nozzle, located in the lower cylindrical part part of the body diagonally to the first supply pipe with a nozzle, while the dust input is made inclined with an angle of inclination to the horizontal α equal to 50-80°, and the cylindrical part of the body, including an additional air chamber, is made with a height H of 1000-2000 mm and a diameter of D 400- 1200 mm.

In addition, the dust washing device contains a fitting for collecting dust samples for analysis, installed on an inclined dust input.

The invention is illustrated by drawings, where:

Fig. 1 shows a general view of the dust-washing device; Fig. 2 - dust washing device, view without the lower side part.

Figure 3 shows a side view of the dust washing device; Fig. 4 - top view of the dust washing device.

List of items used in the drawings: 1 - body; 2 - hatch; 3 - cover; 4 - supply pipe; 5 - nozzle; 6 - drain pipe; 7 - cover; 8 - inclined dust input; 9 - screen; 10 - fitting for collecting dust samples for analysis; 11 - slot for exit of hydraulic mixture (pulp); 12 - additional air chamber (dust damper).

The dust washing device contains a housing 1 with a welded 3 and opening 7 lid, with a cylindrical part, which is an air chamber, at the top of which there is a dust inlet 8, and at the bottom there is a slot for the outlet of the hydraulic mixture 11. On the opposite side of the housing 1 relative to the cylindrical part there is a supply pipe 4 with nozzle 5 for supplying flush water, hatch 2 for servicing nozzle 5 and drain pipe 6. The mentioned device is equipped with a screen 9 to prevent the emission of dry dust outside. The screen 9 is installed with the possibility of blocking the gap for the outlet of the hydraulic mixture 11 by 25-60% (Fig. 1). It should be noted that this range is optimal for preventing the emission of dry dust from the gap, since closing the gap by less than 25% will not significantly prevent release of unwetted dust from the device. Closing the gap by more than 60% will lead to unsatisfactory washing of dust from the cylindrical part of the case and, as a result, to the cessation of unloading dust from the device.

The dust washing device also contains an additional air chamber 12 located above the cylindrical part of the housing, and an additional supply pipe with a nozzle for supplying flush water and a hatch for servicing the nozzle, located in the lower cylindrical part of the housing diagonally to the supply pipe 4 with nozzle 5. Based on experience, it also follows It should be noted that one supply pipe is not enough for satisfactory operation in conditions of high dust load on the device. In this case, the use of three or more pipes seems inappropriate, since it will lead to a significant complication of the design of the apparatus and an unjustified increase in water consumption.

The inclined dust input 8 is made with an angle of inclination to the horizontal α equal to 50-80° (Fig.3), which is optimal for the necessary reduction in the dust flow rate at the inlet to the dust-washing device, since an inclination angle of less than 50° will lead to clogging of the dust inlet due to the fact that the static angle of repose for the vast majority of dusts is at least 50 °. An inclination angle of more than 80° will not significantly affect the deceleration of the dust flow before entering the cylindrical part of the apparatus. A fitting for collecting dust samples for analysis 10 is installed on the inclined dust input 8.

The cylindrical part of the housing 1, including the additional air chamber 12, is made with a height H of 1000-2000 mm and a diameter D of 400-1200 mm (Fig. 4). Reducing the height H to less than 1000 mm will not significantly smooth out fluctuations in excess pressure in the cylindrical part of the housing, which will lead to the emission of dust from the device. Increasing the height H by more than 2000 mm is impractical due to the increase in dimensions, which will lead to the complication or impossibility of placing devices under bunkers under dimensional restrictions. In addition, this significantly complicates and increases the cost of transporting devices. Reducing the diameter of the cylindrical part D to less than 400 mm is impractical due to limitations in the productivity of the apparatus. An increase in D by more than 1200 mm will make the transportation, placement and maintenance of devices more complicated, as well as make them more expensive.

Thus, the inclined dust input 8 makes it possible to reduce the speed of dust falling from a height of up to 30 m at the entrance to the dust washing device. In this case, the direction of the falling dust is oriented in such a way that the dust falls on the back side of the bottom of the housing and is then washed out through the slot 11. The inclined dust input is further strengthened to protect against abrasive wear. Screen 9 prevents the emission of dry dust from the device body. Experience in working under conditions of high dust loads without a screen and with it has shown that screen 9 prevents the emission of unwetted dust from the housing when shaking the collecting electrodes in periodic mode, as well as under conditions of reducing or removing high voltage when shaking the collecting electrodes. Additional air chamber 12 allows you to smooth out excess pressure differences at the time of shaking the electrodes. The second supply pipe makes it possible to more effectively wash out dust from the cylindrical part of the housing 4, which together improves the reliability of the device as a whole.

Claims (2)

1. A dust-washing device containing a housing with an opening and welded lid and a cylindrical part in the form of an air chamber, at the top of which there is a dust input, and at the bottom - a slot for the outlet of the hydraulic mixture, while on the opposite side of the housing relative to the cylindrical part for supplying flush water to the slot for the outlet of the hydraulic mixture, an inlet pipe with a nozzle and a hatch for servicing the nozzle are installed; opposite the slot for the outlet of the hydraulic mixture, a drain pipe is installed, characterized in that it contains a screen to prevent the emission of dry dust, installed with the possibility of blocking the slot for the outlet of the hydraulic mixture by 25-60%, additional an air chamber located above the cylindrical part of the body, an additional inlet pipe for supplying flush water and an additional hatch for servicing the nozzle, located in the lower cylindrical part of the body diagonally to the first inlet pipe with a nozzle, while the dust inlet is made inclined with an angle of inclination to the horizontal α equal to 50 -80°, and the cylindrical part of the body, including the additional air chamber, is made with a height H of 1000-2000 mm and a diameter of D 400-1200 mm. 2. The device according to claim 1, characterized in that it contains a fitting for collecting dust samples for analysis, installed on an inclined dust input.