JP2005206164A - Gas leakage preventive hatch for water supply system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reliably prevent gas from leaking, and to easily attach/detach a cover. <P>SOLUTION: In a gas leakage preventive hatch, a water-sealed groove 2 having a recessed section to surround an opening 1b is formed on an upper face of a top wall 1a of a tank body 1 of an activated carbon treatment tank of a water supply system treatment equipment, and water W is poured to the predetermined level in the water-sealed groove 2, a peripheral edge of a dome-shaped cover 3 is immersed in water W, and the cover is fixed to the tank body 1 by an adjust-fastener 4. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a gas leak prevention hatch for waterworks, which is provided in a treatment tank of a water treatment facility, and is particularly adapted to prevent leakage of gas in the treatment tank.

  Conventionally, water purification technology for water treatment facilities (especially clean water) supports chromaticity, which indicates the degree of water color as a numerical value. For example, the chromaticity in natural water is a yellow to tan coloration due to humic substances (humic substances) found in surface water flowing through peatlands and groundwater in soil areas containing organic matter. The main components of humic substances are humic acid, fulvic acid, etc., but in the case of humic acid, it can be handled by coagulation sedimentation treatment because of its relatively large molecular weight, but in the case of fulvic acid, it is similar to organic substances It is necessary to cope with a combination of activated carbon treatment and ozone treatment. Ozone and activated carbon treatment (including biological activated carbon treatment) is applied to organic substances (precursors) related to the generation of disinfection by-products such as trihalomethane, and air stripping (activated carbon treatment for exhaust) and activated carbon are applied to volatile organic compounds. It is necessary to treat the organic chemicals and pesticides with activated carbon. Then, it is necessary to provide a granular activated carbon treatment facility after the ozone treatment, and it is necessary to consider that the exhaust is treated with activated carbon so as not to release exhausted ozone or volatile organic compounds into the atmosphere (for example, non-patent document). 1).

  Thus, since the quality of raw water has deteriorated in recent years, ozone treatment is performed in place of conventional chlorination. The ozone treatment method is more effective than the chlorination method because the algae and sterilization are completed in a very short time, and the ozone is reduced to harmless oxygen in a short time. It is being evaluated. In an ozone treatment tank that performs ozone treatment, ozone is consumed by organic substances in water during the ozone treatment. Ozone that is not consumed by organic matter or does not dissolve in water diffuses out of the water, but ozone gas has an effect on the human body, so it is necessary to exclude ozone. Usually, the activated carbon treatment tank which performs activated carbon treatment is provided with a hatch for replacing the activated carbon. This hatch has a structure that reliably prevents gas leakage, an opening provided in the tank body, a cover that opens and closes the opening, a sealing material that seals between the tank body and the cover, and a large number of fixing the cover to the tank body It consists of bolts. In general, these openings, covers, seals, etc. are rectangular, and the cover is made of corrosion- and weather-resistant stainless steel (SUS316, etc.) or corrosion-resistant steel, and the seal is made of flat rubber (EPDM). Etc.). And a cover may be provided double.

  An invention of a device that locks a cover that is attached to and detached from an opening of a water treatment tank such as a septic tank is disclosed under the name “water treatment tank cover locking device”. In this lock device, when the cover lid is placed on the lid receiving portion and the opening of the water treatment tank is covered, the fixed engagement piece is fitted in the first recess portion. When the movable engagement piece overlaps and engages with the fixed engagement piece fitted in the first recessed portion from below, the position of the operation shaft is maintained at that position against the force of the spring body. The head of the operation shaft is held at a position where it does not protrude from the upper surface of the cover body. Further, when the movable engagement piece is swung to a position where it does not overlap the fixed engagement piece, the operating shaft is moved upward by the force of the spring body, and its head protrudes from the upper surface of the cover body. The second recessed portion includes an engaging portion on the upper surface side of the cover body. In addition, the cover main body has a handle unit, and the handle unit is held by a hand so as to be attached to and detached from the cover receiving portion (see, for example, Patent Document 1).

“Water Purification Technology Guidelines” 2000 edition, issued by Water Technology Center, P.A. 28-29 and P.I. 30 JP 09-125435 A (paragraph 0022 and paragraph 0023 and FIGS. 1, 4 and 5)

  Since the lock device for the water treatment tank cover has a space around all the fixed engagement pieces other than the fixed engagement pieces with which the movable engagement pieces engage, the surface material of the cover main body and the cover receiving portion Is not necessarily sealed, and is not intended to reliably prevent gas leakage in the water treatment tank. Therefore, this water treatment tank cover locking device cannot be applied to a conventional hatch structure of an activated carbon treatment tank that needs to prevent gas leakage. Therefore, in the conventional hatch structure of the activated carbon treatment tank, the cover is fixed to the tank body using conventional sealing and fixing means, that is, a sealing material and a large number of bolts.

For this reason, since the conventional hatch attaches and detaches a large number of bolts when attaching and detaching the cover, it has a problem that it takes a lot of time to attach and remove the cover. In addition, since the cover is square, cornering is necessary, and the bolt tightening force is not uniform. And since a sealing material is a square and flat type, when a cover is fastened with many volt | bolts, there exists a problem that a sealing material is wrinkled.
In addition, since the cover is made of stainless steel or provided twice, there is a problem that the material cost is high. Furthermore, since the cover is heavy, a chain block and a crane for attaching and detaching the cover are necessary, and there is a problem that the equipment cost is high.

This invention was made in order to solve the above-mentioned subject, and the 1st objective is for the waterworks which can prevent the leakage of gas surely and can attach or detach a cover easily. A gas leakage prevention hatch is obtained.
Moreover, the 2nd objective is to obtain the gas leak prevention hatch for waterworks which can reduce material cost, equipment cost, maintenance cost, etc.

The water leak prevention hatch for waterworks according to the present invention comprises a cover, a water sealing groove, and a fixing means.
Moreover, in the gas leak prevention hatch for waterworks which concerns on this invention, it consists of a cover with a water supply / drain port and a fixing means.

  According to the present invention, it is possible to reliably prevent gas leakage by providing the water sealing groove. In addition, as a fixing means, not only the troublesome work of tightening a large number of bolts at the time of removal is unnecessary, but also it can be configured to use a one-touch adjustment fastener, so the cover can be easily attached and detached. Can do. Further, since the cover can be made of a light material such as FRP, equipment such as a chain block and a crane that has been necessary in the past is unnecessary, and the equipment cost can be reduced. In the case of a cover containing water, if the cover is made of a light material and water is removed from the cover, the cover can be made extremely light and the cover can be easily attached and detached. In this case, the fixing means can be made unnecessary by increasing the amount of water.

Embodiment 1 FIG.
As shown in FIG. 1, in the gas leak prevention hatch for waterworks according to Embodiment 1 of the present invention, for example, a water seal groove 2 having a concave cross section is provided in a tank body 1 of an activated carbon treatment tank of a water treatment facility. The peripheral edge of the cover 3 is accommodated in the sealing groove 2, and the cover 3 is fixed to the tank body 1 by a plurality of adjusting fasteners (fixing means) 4. Then, by injecting water W into the water sealing groove 2, gas leakage from the tank body 1 is prevented.

  The top wall 1a of the tank body 1 is provided with an opening 1b for replacing the activated carbon. The shape of the opening 1b is circular, and the diameter is preferably about 2 m. The width of the water seal groove 2 is preferably about 300 mm and the height is preferably about 400 mm. And assuming the most intense generation of gas inside the tank body 1, assuming that the maximum pressure inside the tank body 1 at that time is 3000 Pa, the depth of the water W in the water seal groove 2 is about 300 mm. It is preferable to do this. In this case, depending on the pressure inside the tank body 1, the height of the surface of the water W inside the cover 3 may be lower than the outside of the cover 3 due to the gas pressure. In addition, although the diameter of the opening 1b is about 2 m, it can be changed depending on the workability and the situation of taking in and out of the activated carbon. Moreover, although the width | variety of the water sealing groove | channel 2 shall be about 300 mm, this can also be changed by construction or a maintenance condition. The height of the water sealing groove 2 is about 400 mm, but can also be changed by the gas pressure from the activated carbon treatment tank.

  The water seal groove 2 will be described in detail. The water seal groove 2 is provided on the top surface of the top wall 1a of the tank body 1 so as to surround the opening 1b of the tank body 1. The water sealing groove 2 includes an annular bottom plate 2a provided on the top surface of the top wall 1a, an inner plate 2b raised substantially vertically from the inner edge of the bottom plate 2a, and an outer plate raised substantially vertically from the outer edge of the bottom plate 2a. 2c. The inner diameter of the inner plate 2b is preferably matched with the inner diameter of the opening 1b, but there is no problem even if it is not matched. Moreover, although the height of the inner board 2b and the outer board 2c is made to correspond, it does not necessarily need to be made to correspond.

  Such a water-sealed groove 2 is fixed to the top wall 1a of the tank body 1 after being formed as a separate body. Therefore, the water seal groove 2 can be formed of any material. However, it goes without saying that the water sealing groove 2 can be integrally formed of the same material as that of the top wall 1a of the tank body 1. In cold weather or in cold regions, it is preferable to provide means for preventing the water W from freezing, such as an antifreeze liquid or a heater.

  On the other hand, the cover 3 is a dome-shaped cover body 3a that covers the opening 1b of the tank body 1, and an annular fixed body that protrudes outward in the vicinity of the periphery of the cover body 3a or has a sleeve from the horizontal. It is comprised from the board 3b. The peripheral edge of the cover main body 3a is positioned approximately in the middle of the inner plate 2b and the outer plate 2c of the water sealing groove 2 and is submerged in the water W. The fixing plate 3b of the cover 3 is shaped such that its outer edge engages with the upper end surface of the outer plate 2c of the water sealing groove 2.

  Such a cover 3 is made of ozone resistant FRP (fiber reinforced plastic). As shown in FIG. 2, the cover 3 includes an innermost layer 11 mainly composed of a heptic acid-based polyester resin, an intermediate layer 12 mainly composed of an orthophthalic acid-based polyester resin, and an outermost layer 13 serving as a gel coat layer. The innermost layer 11 includes an organic fiber 11a and serves as a corrosion-resistant layer. The intermediate layer 12 includes glass fibers 12a and serves as a strength layer. The cover 3 is preferably provided with a handle (not shown).

  The adjustment fastener 4 is a presser fitting, and fixes the cover 3 to the tank body 1 by a one-touch operation. Needless to say, the plurality of adjust fasteners 4 are preferably provided on a diagonal line. In FIG. 1, the cover 3 is fixed to the tank body 1 by the adjust fastener 4, but can be configured to be fixed to the water seal groove 2. In addition, when stopping at two places, it is also possible to fix one side and use the adjustment fastener 4 only on the other side.

  In the gas leakage prevention hatch for waterworks having such a configuration, when closing the opening 1b of the tank body 1, after the water W is poured into the water sealing groove 2 to a predetermined water level, the periphery of the cover 3 is moved to the water sealing groove 2. The outer peripheral edge of the fixing plate 3 b of the cover 3 is engaged with the upper end surface of the outer plate 2 c of the water sealing groove 2. Then, all the adjustment fasteners 4 are locked. Thereby, the water W in the water seal groove 2 prevents the gas inside the tank body 1 from leaking out. On the other hand, when removing the cover 3, the cover 3 may be lifted after all the adjustment fasteners 4 are unlocked.

  Thus, in the gas leak prevention hatch for waterworks of Embodiment 1, the tank main body 1 can be sufficiently sealed by the water sealing groove 2 and the cover 3. In addition, the cover 3 can be attached and detached simply by locking or unlocking each of the plurality of adjust fasteners 4 by one-touch operation. Therefore, since the conventionally used bolt is not used at all, the attaching / detaching operation of the cover 3 becomes extremely easy. In addition, since the cover 3 is made of FRP, the cover 3 becomes extremely light, equipment such as a chain block and a crane, which has been necessary in the past, is unnecessary, and this contributes to easy attachment / detachment of the cover 3. In addition, material costs and equipment costs can be reduced. Furthermore, since a conventional sealing material is unnecessary, material costs and maintenance costs are reduced.

  In addition, if it inserts in order to supplement the sealing material which is not shown in figure between the baseplate 2a of the water seal groove 2, and the periphery of the cover main body 3a, safety | security can be improved further. As the sealing material in this case, an O-ring, a flat sealing material, or the like having a shape suitable for the bottom plate 2a of the water sealing groove 2 and the peripheral edge of the cover body 3a may be selected. Unlike the conventional method of tightening with bolts, this can be reused by applying pressure to the whole like the adjust fastener 4. Further, if a water level sensor is provided in the water sealing groove 2, the amount of water W can be monitored, and maintainability can be improved. In addition, the cover 3 has a circular dome shape in accordance with the shape of the opening 1b of the tank body 1. However, other shapes such as a square dome shape, a circular flat shape, and a square flat shape may be used. Then, instead of the adjust fastener 4, other appropriate fixing means that exhibits its function with a small number of steps can be used.

Embodiment 2. FIG.
As shown in FIG. 3, in the gas leak prevention hatch for waterworks according to Embodiment 2 of the present invention, the tank body 5 is sealed by a hollow cover 6 and a seal member 7, and the cover 6 is tanked by a plurality of adjust fasteners 8. It is fixed to the main body 5. The top wall 5a of the tank body 5 is provided with an opening 5b having an inner diameter similar to that of the first embodiment. Further, an annular protrusion 5c is integrally provided on the top surface of the top wall 5a so as to face upward, and the inner diameter of the protrusion 5c is matched with the inner diameter of the opening 5b. However, if there is no problem in the installation and operation of the adjust fastener 8, the protrusion 5c may not be provided. The diameter of the opening 5b is about 2 m as in the first embodiment, and the width of the protrusion 5c, that is, the thickness in the horizontal direction is about 300 mm.

  Here, the cover 6 is made of an ozone resistant FRP similar to the cover 3 of the first embodiment. The cover 6 includes a bottom plate 6a having an outer diameter substantially the same as the outer diameter of the protrusion 5c, a top plate 6b opposed to and parallel to the bottom plate 6a, and a side plate 6c connecting the peripheral edges of the bottom plate 6a and the top plate 6b. Formed from. The distance between the bottom plate 6a and the top plate 6b of the cover 6 is about 300 mm, and the inside of the cover 6 is a water W containing chamber 6d. The top plate 6 b is formed with a water supply / drain port 6 e used for supplying or removing water W, and the water supply / drain port 6 e is sealed by a sealing means 9. The sealing means 9 may be a push plug, a screw cap, a check valve, or the like, but is not limited thereto, and other appropriate means that enables easy water supply / drainage can be used.

  When closing the opening 5 b of the tank body 5, the seal member 7 is disposed on the upper surface of the protrusion 5 c of the tank body 5, an empty cover 6 is placed on the seal member 7, and then the adjust fastener 8 is used. The cover 6 is fixed to the tank body 5. Then, water W is injected from the water supply / drainage port 6e of the cover 6 into the accommodation chamber 6d by a water supply unit (not shown), and when it is almost full, the water supply / drainage port 6e is sealed by the sealing unit 9. Thereby, the weight of the cover 6 and the water W presses the sealing member 7, and the cover 6 and the sealing member 7 reliably seal the opening 5 b of the tank body 5, thereby preventing the leakage of gas inside the tank body 5.

  On the other hand, when removing the cover 6, the sealing means 9 is first removed, and then the water W inside the cover 6 is sucked by a drain means such as a pump (not shown). Then, after the inside of the cover 6 is almost empty, all the adjustment fasteners 8 are unlocked, and the cover 6 that has become lighter with the water W removed is lifted.

  In Embodiment 2, since the weight of the cover 6 can be increased by injecting water W into the storage chamber 6d of the cover 6, the opening 5b of the tank body 5 can be sufficiently sealed. In addition, since the weight of the cover 6 can be reduced by removing the water W, equipment such as a chain block and a crane, which has been conventionally required, becomes unnecessary. Therefore, the attaching / detaching operation of the cover 6 becomes extremely easy, and the material cost and the equipment cost can be reduced.

  In addition, although the water supply / drain port 6e of the cover 6 was provided in one place, if it provides in two or more places, water supply / drainage time can be shortened. Moreover, although the cover 6 was circular corresponding to the opening 5b of the tank body 5, it can be matched to the existing shape. For example, when the shape of the opening 5b of the tank body 5 is a square, the shape of the cover 6 can be a square corresponding to the shape.

Embodiment 3 FIG.
As shown in FIG. 4, in the gas leak prevention hatch for waterworks according to Embodiment 3 of the present invention, the cover 6A has the same bottom plate 6a, top plate 6b, side plate 6c, storage chamber 6d, water supply / drainage port as those in Embodiment 2. 6e and sealing means 9 are provided. However, in the third embodiment, the side plate 6c of the cover 6A is integrally extended downward, and the skirt portion 6f that fits outside the protrusion 5c of the tank body 5 is provided. Others are the same as in the second embodiment. Therefore, in the third embodiment, the position of the cover 6A with respect to the protrusion 5c of the tank body 5 can be easily and reliably determined by the skirt portion 6f, and other effects similar to those of the second embodiment can be achieved. .

Embodiment 4 FIG.
As shown in FIG. 5, in the gas leak prevention hatch for waterworks according to Embodiment 4 of the present invention, the cover 6B has the same bottom plate 6a, top plate 6b, side plate 6c, storage chamber 6d, water supply / drainage port as those in Embodiment 2. In addition to having 6e and the sealing means 9, in this Embodiment 4, the drain port 6g for discharging the water W is provided in the lower part of the side plate 6c of the cover 6B, and this drain port 6g is sealed. 10 is sealed. Therefore, in the fourth embodiment, the water W can flow out from the inside of the cover 6B, the drainage means in the second embodiment is not necessary, and the other effects similar to those in the second embodiment can be obtained. .

Embodiment 5 FIG.
As shown in FIG. 6, in the water leak prevention hatch for waterworks according to Embodiment 5 of the present invention, the opening 5 b of the tank body 5 </ b> A is sealed with a spherical and hollow cover 21. For this reason, the tank body 5A has the same top wall 5a, opening 5b, and projection 5c as in the second embodiment, and in this fifth embodiment, an inclined surface 5d that houses the lower portion of the cover 21 is formed above the projection 5c. Is provided. The cover 21 is made of FRP as in the second embodiment, and the inside thereof is a water W accommodating chamber 21a. In the vicinity of the uppermost part of the cover 21, a vent 21b for facilitating water supply / drainage is provided. A water supply / drain port 21c is formed below the cover 21, and the water supply / drain port 21c is sealed by a sealing unit 22 similar to the sealing unit 9 of the second embodiment or the sealing unit 10 of the fourth embodiment. It is. In addition, if the top wall 5a can be manufactured in a shape suitable for a gas leak prevention hatch for waterworks at the time of construction, the protrusion 5c may not be provided.

  When closing the opening 5b of the tank body 5A, the empty cover 21 is first placed on the inclined surface 5d of the tank body 5A while the water supply / drain port 21c is positioned downward, and then the water W is covered using water supply means. 21 is pumped from the water supply / drain port 21c to the storage chamber 21a. Thereby, as the amount of water W in the storage chamber 21a of the cover 21 increases, the cover 21 comes into pressure contact with the inclined surface 5d of the tank body 5A and seals the opening 5b of the tank body 5A. On the other hand, when removing the cover 21, the sealing means 22 is removed, the water W is allowed to flow out, and the empty cover 21 is lifted.

  In this fifth embodiment, since the amount of water W is larger than in the first, second, and fourth embodiments, the adjustment fasteners 4 and 8 that are necessary in the first, second, and fourth embodiments are not required. In addition, the same effects as those of the second embodiment can be obtained. In addition, if the sealing member 23 is arrange | positioned between 5 d of inclined surfaces of the tank main body 5A, and the outer surface of the cover 21, the sealing degree between the tank main body 5A and the cover 21 can further be improved. In this case, as the shape of the seal member 23, an O-ring or a flat seal material having a shape suitable for the contact portion between the tank body 5A and the cover 21 may be selected.

  As shown in FIG. 7, the water supply facility is composed of a coagulation sedimentation tank 31, an ozone treatment tank 32, an activated carbon treatment tank 33, and a rapid filtration layer 34 in order from the upstream side. The water leak prevention hatch for waterworks concerning ~ 5 was applied. The activated carbon treatment tank 33 was a downward flow fixed bed system using granular activated carbon, the linear velocity was 360 m / d, and coconut shell activated carbon having an effective diameter of 1.1 mm was used as the granular activated carbon with a layer thickness of 2 m. The diameters of the openings 1b and 5b of the tank bodies 1, 5, and 5A were set to 2 m as described above. In any of the first to fifth embodiments, ozone gas did not leak from the tank bodies 1, 5, and 5A, and equipment such as a chain block and a crane was not required for maintenance.

  As shown in FIG. 8, the position of the activated carbon treatment tank 33 is changed as compared with the first embodiment, and the water supply equipment is sequentially arranged from the upstream from the coagulation sedimentation tank 31, the rapid filtration layer 34, the ozone treatment tank 32, and the activated carbon treatment tank. 33, and applied to the activated carbon treatment tank 33 the gas leak prevention hatch for waterworks according to the first to fifth embodiments. The activated carbon treatment tank 33 was a downward flow fixed bed system using granular activated carbon, the linear velocity was 500 m / d, and coconut shell activated carbon having an effective diameter of 0.6 mm was used as the granular activated carbon with a layer thickness of 2 m. The diameters of the openings 1b and 5b of the tank bodies 1, 5, and 5A of the activated carbon treatment tank 33 were set to 2 m as described above. In this case, the same effect as in Example 1 could be obtained.

It is sectional drawing of the gas leak prevention hatch for waterworks which shows Embodiment 1 of this invention. 3 is a schematic diagram showing a composition of a cover made of ozone resistant FRP according to Embodiment 1. FIG. It is sectional drawing of the gas leak prevention hatch for waterworks which shows Embodiment 2 of this invention. It is sectional drawing of the gas leak prevention hatch for waterworks which shows Embodiment 3 of this invention. It is sectional drawing of the gas leak prevention hatch for waterworks which shows Embodiment 4 of this invention. It is sectional drawing of the gas leak prevention hatch for waterworks which shows Embodiment 5 of this invention. It is a block block diagram which shows arrangement | positioning of the various processing tanks of a waterworks installation. It is a block block diagram which shows arrangement | positioning of the various processing tanks of a waterworks installation.

Explanation of symbols

1, 5, 5A Tank body 1a, 5a Top wall 1b, 5b Opening 2 Water seal groove 3, 6, 6A, 6B, 21 Cover 4, 8 Adjust fastener (fixing means)

Claims (2)

  A gas leakage prevention hatch for waterworks comprising a cover, a water seal groove, and a fixing means.   A gas leakage prevention hatch for waterworks, characterized by comprising a cover with a water supply / drain port and a fixing means.

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