| 摘要 |
<p>PURPOSE:To prevent the leakage of dangerous gas and discharge dusts efficiently by opening airtight discharge valves for a predetermined time with plural stages of valve boxes provided in a dust separating part and controlling the gas supply to a pressure equalizing box by the actuation of gas detecting sensors. CONSTITUTION:Captured dusts are conducted through a duct 2 into an intermediate accumulation box. When the dusts accumulate to a predetermined amount, the uppermost stage airtight discharge valve 5a opens by a predetermined time, and the dusts fall into the uppermost stage valve box 4. Thence, the airtight discharge valve 5b of the next stage opens for a predetermined time, and the dusts fall into an equalizing box 6. Consequently, the dangerous gas in the duct 2 accumulates in an intermediate accumulation box 3 and does not flow downward. An inert gas is fed into the box 6. The gaseous pressure in this box 6 is controlled by opening and closing of a control valve 15 in such a manner that the detected values of the 1st sensor 9a detecting the pressure of the dangerous gas in the duct 2 and the 2nd sensor detecting the gaseous pressure of the discharge space are equalized. Finally, the dusts are discharged by opening and closing of a controlled valve driving device 8c.</p> |
