JP5751244B2 - Gas purification device - Google Patents

Description

  The present invention relates to a gas purification device, and more particularly to a gas purification device including an activated carbon element that adsorbs corrosive components.

  In order to remove sulfur oxide, hydrogen sulfide, and the like from the air, it is known to use activated carbon impregnated with potassium iodide (Japanese Patent Laid-Open No. 2003-10688). Japanese Patent Application Laid-Open No. 9-262273 describes using activated carbon carrying copper chloride or a metal oxide in order to remove malodorous components such as hydrogen sulfide.

  Japanese Patent Application Laid-Open No. 2004-89963 describes a method of adsorbing and removing an odor component by adjusting the humidity of the odor component-containing gas to a relative humidity of 85% or more and then bringing it into contact with an activated carbon-containing honeycomb adsorbent.

  Japanese Patent Application Laid-Open No. 2000-157620 describes a deodorizing device that deodorizes by passing a waste odor component-containing air containing hydrogen sulfide or the like through a bed filled with activated carbon by a fan.

JP2003-10688 JP-A-9-262273 JP 2004-89963 A JP 2000-157620 A

  If the gas to be treated containing a corrosive component is continuously passed through an activated carbon element such as an activated carbon molded body or a packed bed, the adsorption capacity of the activated carbon gradually decreases, and finally the activated carbon breaks through and the corrosive component is formed. To leak.

  Conventionally, in order to detect leakage of this corrosive component, gas analysis is performed, or a test piece made of a metal piece is arranged on the outlet side of the adsorption device, and the presence or absence of leakage is determined from the corrosion state of this test piece. However, there are disadvantages that it takes a long time to make a determination and can only be detected after a leak has actually occurred.

  An object of the present invention is to provide a gas purifying apparatus capable of replacing an activated carbon element at an appropriate time before the leakage of corrosive components actually starts and without becoming too early.

The gas purification device of the present invention includes a housing through which a gas to be treated passes, an activated carbon element that adsorbs a corrosive component, a fan that circulates the gas to be treated in the activated carbon element , and the activated carbon. A pre-filter provided across the housing upstream of the element; an after-filter provided across the housing downstream of the activated carbon element ; and a gas passage differential pressure of the activated carbon element detecting means for detecting means and the gas passage of, a gas purifying device provided with a determining means the replacement timing of the activated carbon element based on the detected value of the detection means, said determining means, the gas The activated carbon element includes a gas-permeable inner cylinder and an outer cylinder, and an inner portion of the activated carbon element. A ring-shaped first end plate that closes one end side of the space between the outer cylinder and the outer cylinder, a second end plate that entirely closes the other end side of the activated carbon element, the inner cylinder and the outer cylinder, The granular activated carbon is filled with potassium iodide, and the amount of potassium iodide added is 0.01 to 10 wt% of potassium iodide impregnated activated carbon.

  When the gas to be treated containing the corrosive component is passed through the gas purification apparatus of the present invention, the corrosive component is adsorbed on the activated carbon element, and the purified gas is taken out. If the gas supply to the gas purifier is continued, the pressure loss of the activated carbon element increases due to the consolidation of the activated carbon and the air volume decreases. In the present invention, at least one of the gas passage differential pressure and the gas passage amount of the activated carbon element is detected, and the replacement timing of the activated carbon element is determined based on this. For example, it is possible to replace the activated carbon element at an appropriate time by determining the replacement timing of the activated carbon element when the passing differential pressure is equal to or higher than a predetermined value or the passing amount is equal to or lower than the predetermined amount. .

It is sectional drawing of the longitudinal direction of the gas purification apparatus which concerns on embodiment. It is sectional drawing of an adsorption | suction unit, (a) A figure is sectional drawing of the axial center direction of an activated carbon element, (b) A figure is the BB sectional drawing of (a) figure.

  Hereinafter, embodiments will be described with reference to the drawings. As shown in FIG. 1, the gas to be treated containing corrosive components is introduced from the duct 1 to the adsorption unit 2, and the purified gas flows out through the duct 3.

  The adsorption unit 2 includes a cylindrical housing 4, a prefilter 5 made of a non-woven fabric or the like provided so as to cross the upstream end of the housing 4, and a space between the prefilter 5 and the activated carbon element 7. After-arrangement comprising: a fan 6 arranged; the activated carbon element 7 provided so as to transmit air supplied from the fan 6; and a HEPA filter provided so as to cross the downstream end of the housing 4 And a filter 8.

  As shown in FIG. 2, the activated carbon element 7 closes one end side of a space between the inner cylinder 10 and the outer cylinder 11, and a breathable inner cylinder 10 and an outer cylinder 11 each made of a perforated plate, a mesh or the like. A ring-shaped front end plate 12, a rear end plate 13 that completely closes the other end of the activated carbon element 7, and a granular activated carbon 14 filled in a space between the inner cylinder 10 and the outer cylinder 11. .

  In this embodiment, activated carbon is impregnated with potassium iodide. The amount of potassium iodide is preferably 0.01 to 10 wt%.

  A ring-shaped mounting seat 15 having a center hole 15 a is provided on the inner surface of the housing 4. The front end plate 12 of the activated carbon element 7 is detachably attached to the attachment seat 15 with bolts or the like. The center hole 15a and the inner cylinder 10 have substantially the same diameter and are arranged coaxially. The diameter of the outer cylinder 11 is smaller than that of the housing 4. The outer cylinder 10 is installed coaxially with the housing 4, and a ventilation space is formed between the outer peripheral surface of the outer cylinder 10 and the inner peripheral surface of the housing 4. The gas passage linear velocity of the activated carbon element 7 is preferably 0.2 m / s or more, particularly preferably about 0.3 to 0.35 m / s.

  The ducts 1 and 3 are provided with pressure sensors 20 and 21, respectively, and their detection signals are input to the determination device 22. The duct 3 is provided with a flow rate sensor 23 such as a hot-wire anemometer, and a detection signal of the flow rate sensor is input to the determination device 22.

  In the gas purification apparatus configured as described above, when the fan 6 is driven, the gas to be treated containing corrosive components passes through the prefilter 5 from the duct 1 and flows into the adsorption unit 2, and the inner cylinder 10 of the activated carbon element 7. Then, it passes through the filling portion of the activated carbon 14 and the outer cylinder 11, and the purified gas passes through the after filter 8 and flows out to the duct 3. The fan 6 is rotated at a constant speed and the operation is continued. Then, the determination device 22 determines the difference between the pressure sensors 20 and 21 (differential pressure) and the detected flow rate of the flow rate sensor 23 over time.

  When the operation is continued, the differential pressure gradually increases and the passing flow rate gradually decreases. Therefore, when the differential pressure is equal to or higher than a predetermined value set in advance or the flow rate is lower than the predetermined flow rate, the activated carbon element 7 is removed from the mounting seat 15 and replaced with a new (or activated carbon regenerated) activated carbon element 7. .

  It is preferable that a differential pressure or a flow rate when the leakage of the corrosive component starts from the activated carbon element 7 is obtained in advance, and a value in consideration of the safety factor is set as the predetermined value or the predetermined flow rate.

  When the leak of the corrosive component is detected, the notification means for notifying the breakthrough of the activated carbon is activated. The notification means includes, but is not limited to, a warning lamp lighting means, a warning sound generation means, a warning mail transmission means, and the like.

  Thereby, the activated carbon element 7 can be replaced at an appropriate time before the corrosive component leaks and without being excessively early.

  Note that the measurement of the differential pressure and the flow rate sensor may be performed continuously or intermittently (for example, once every several hours to several months).

  The gas may be circulated in a transient manner or circulated.

  Experiments were conducted to confirm the effects of the present invention.

  An activated carbon element having an inner diameter of 200 mm, an outer diameter of 350 mm, and a length of 500 mm and having a granular activated carbon filling amount of 15 kg and having a structure shown in FIG. 2 was installed in the housing of FIG. The granular activated carbon has a particle size of 90 wt% with a particle size of 2.4 to 4.7 mm. Activated carbon was impregnated with 0.5 wt% potassium iodide. Air adjusted to a hydrogen sulfide concentration of about 100 ppb was passed through the gas purification device, and the differential pressure and the air volume were measured. The presence or absence of breakthrough of the activated carbon was determined by the change in the hydrogen sulfide concentration measured in the outlet duct of the housing. The results are shown in Table 1.

From Table 1, it was confirmed that there was a correlation between activated carbon breakthrough, air volume reduction, and differential pressure increase. Also, from Table 1, when the air volume falls below 11 m ³ / min, when the air volume falls below 75% of the initial volume, when the differential pressure exceeds 190 Pa, or the differential pressure exceeds 140% of the initial value. It was found that it could be determined that the activated carbon broke through at any point in time. Therefore, for example, a value at the time of 15 months before breakthrough is set as a set value, and when this set value is reached, the activated carbon element is replaced at an appropriate time by replacing the activated carbon element.

DESCRIPTION OF SYMBOLS 1,3 Duct 2 Adsorption unit 4 Housing 5 Pre filter 6 Fan 7 Activated carbon element 8 After filter 14 Activated carbon 20, 21 Pressure sensor 22 Judgment device 23 Flow rate sensor

Claims (3)

A housing through which the gas to be treated passes;
An activated carbon element that adsorbs corrosive components provided in the housing ;
A fan that distributes the gas to be treated to the activated carbon element ;
A pre-filter provided so as to cross the housing on the upstream side of the activated carbon element;
An after filter provided so as to cross the housing on the downstream side of the activated carbon element;
A means for detecting a gas passage differential pressure and a means for detecting a gas passage amount of the activated carbon element;
A gas purifying apparatus provided with a judging means for judging replacement time of the activated carbon element based on the detected value of the detection means,
The determination means includes a gas passage differential pressure determination means and a gas passage amount determination means,
The activated carbon element includes a breathable inner cylinder and outer cylinder, a ring-shaped first end plate that closes one end side of a space between the inner cylinder and the outer cylinder, and the other end side of the activated carbon element over the entire surface. A second end plate that is closed, and granular activated carbon filled in a space between the inner cylinder and the outer cylinder,
The granular activated carbon is a potassium iodide-impregnated activated carbon having a potassium iodide addition amount of 0.01 to 10 wt%. 2. The gas purification apparatus according to claim 1, wherein the pre-filter is made of a non-woven fabric, and the after-filter is made of a HEPA filter . 3. The gas purification device according to claim 1, wherein the fan rotates at a constant speed so that a gas passage linear velocity of the activated carbon element is 0.2 to 0.35 m / sec .

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