1, problems

1) filter bag filter selection area too small, the actual volume of inadequate ventilation, crusher machines blanking the mouth of crusher dust mask and it is difficult to form micro-cavity negative pressure, resulting in higher positions dust environment (see table 1).

Table 1 of the situation before and after the dust environment mg/m3
Measuring point Crusher corner posts belt machine at the exit of dust emissions (superscript status)
Transformation of the former 12.2 27.7
After transformation 4.3 5.3 27


2) When the crusher broken materials, high humidity (after the rain or materials Linshui after), precipitator dust particles entering a broken stem coarse material, easy to paste bag filter bags under the feeder easy plug, bag filter ventilation resistance caused substantial increase in ventilation capacity decreased dust serious.

3) Figure 1 Layout of the process, precipitator dust into the pipeline, the entrance to the bend of the increasing resistance to the system, bend parts wear and dust easily plug. A screw conveyor and sub-transmission grid round of the down bag filter dust collection, power consumption increase, machinery maintenance workload increase; often need round demolition of the grid under the feeder, and the passage of time, the feeder flange leakage, Leakage increased dust hopper.


4) belt of the whereabouts of the materials in the process, materials with air and the dust cover confined within the dust cover gas through a crack in the wall outlet to the hood, and the spread of pollution of the environment. In addition, since the corner of the dust belt point set up properly, and it is precipitator both of the lower levels and stop-gap dust belt almost no impact. Therefore, on the 5th rock breaking machine running, the ESP are not running off, the lower belt machine has been in the diffuse dust, the process arrangement shown in Figure 2.

Figure 2 of the former belt-corner layout of dust

5) In order to reduce air leakage due to a broken shell of dust in the actual production, when the materials are often in the dry entrance Linshui crusher, and the results exacerbated paste bag filter bags and bags under the feeder plug . The bag filter cleaning is intermittent, when Duster normal working hours, the grid is also a round of air leakage problems not to be neglected.
6) bag filter and component parts more the fault not only affects the normal dust, and increased equipment maintenance workload. Maintenance of equipment from the statistics, with the poor quality of equipment failure is caused more important reason.

2 technical measures

1) crusher machine and conveyor system at the corner of bag filter were updated to LNGM64-4 and LNGM4-8 bag filter, its technical performance parameters in table 2. According to the characteristics of dust, a water repellent and oil filter. LNGM4-8 bag filter open layout, its insulation waterproof shell for processing. In order to ensure reliable operation of equipment, in the acquisition of bag filter attention should be paid to the key accessories brand and model specifications, in order to reduce the failure rate of equipment.


Table 2 crusher bag filter technical performance
Technical parameters HZ-Ⅱ CR-20/10-LNGM64-4 LNGM4-8
Dealing with air volume / (m3 / h) 24000 ~ 390003 500 180003 000
Filtration area / m2 118.81 20256 32
The number of bags / a 105 20256 60
Filtration velocity / (m / min) 3.37 to 5.47 2.9 1.17 1.56
Resistance / Pa 1177 <1200 <1 400
Cleaning mode pulse-pulse-pulse me me Pulse
Room /-4 1 4 4

2) improving layout bag filter technology, according to the direction of belt machine layout lithotripsy machine precipitator, will be the standard type bag filter dust hopper ash bucket of dual structure, so Taiwan lifted a screw conveyor, elevation bag filter, into the duct to the layout (of the angle of the wind); set up in the air inlet into the bellows so that the material I crusher dust precipitator direct access to the intake air box, saving elbow, reduce the resistance of the system and improve the efficiency of the ESP. Its layout of Figure 3. Wind dust hopper lock using single flap valve, eliminating a round of the sub-grid electrical feeder and reduce secondary dust, raising dust effects.

Figure 3 after the transformation process layout crusher dust

3) belt at the corner of the site conditions restricting dust, dust mask chute and can not be changed, dust layout of Figure 4 taken in the form of the micro-dust mask in a state of vacuum to remove dust belt machine.

Figure 4 modified belt-corner layout of dust

4) should be beneficial to both filter and pulse valve life, but also take into account the gray dust hopper off the dust, in order to improve the crusher and conveyor system integrated dust, and in broken dry materials, may, if necessary, Crusher materials appropriate Linshui entrance (called a crusher 10 ~ 20 min after).
5) strengthening the management of dust removal equipment, periodic inspection of the dust cover closed and found that dealing with problems in a timely fashion. On the status of the environment and bag filter dust emissions targets management assessment, regular monitoring of dust and use economic leverage to mobilize posts staff enthusiasm for work, raising the level of dust removal equipment maintenance, minimize dust pollution.

Experience with the effects of 3
1) After the transformation, crusher and conveyor system at the corner of the environment to achieve the design requirements, exports almost see precipitator dust emissions (see table 1). Run more than three months, the maintenance of the equipment has not.
2) 2-bag filter, bag filter media phenomenon without paste.
3) It must be noted that dust mask block dust screens dust effects on the structure of a great impact on the block dust screens can not use an old belt just hang on, the old belt   be should cut15 to 20 mm wide, 1 / 4 part of superposition into a curtain (the northern winter-like windshield screens), both for the convenience of such materials on the belt of passage are confined good performance.
4) To ensure that there is a good job environment, in addition to strengthening post workers dedusting equipment maintenance, maintaining jobs and sanitation equipment is also very necessary.