JP2003290733A - Waste landfill disposal site, gas collecting apparatus and gas treating apparatus at the site - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To treat a gas produced in a waste landfill disposal site without diffusing to the surroundings. <P>SOLUTION: A collecting and distributing pipe 11 for exuded water is placed in the bottom of the waste landfill disposal site 10, a gas releasing pipe 13 with its lower end communicating with the water collecting and distributing pipe, having upper end opened to the air and having a gas flow port on the peripheral wall is erected from the water collecting and distributing pipe, a gas suction means F communicating with the collecting and distributing pipe for the exuded water is provided and a gas treating means 15 for treating the gas sucked by the gas sucking means is installed. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a waste landfill processing site for landfilling waste, a gas collecting apparatus and a gas processing apparatus therefor.

[0002]

2. Description of the Related Art At a waste landfill disposal site, in addition to methane and carbon dioxide gas, gases containing hydrogen sulfide, methyl sulfide, methyl disulfide, methyl mercaptan, ammonia, etc. are generated from the layer of the input waste. It causes problems such as landfill work environment due to bad odor and environmental pollution around the landfill site, fire, and in a broad sense, environmental destruction due to emission of greenhouse gases.

[0003]

For this reason, in many existing disposal sites, a pipe for collecting and distributing leachate is laid at the bottom of the recessed part constructed by excavating the ground, and the upper end opens to the atmosphere and the peripheral wall There are many quasi-aerobic landfill structures in which the lower end of a gas vent pipe having a gas flow port is erected in communication with the water collection and distribution pipe, and air naturally flows into the waste layer that generates gas under anaerobic conditions. However, due to the nature of the landfill waste, the response cannot be made in time and the problem of gas has not been resolved. In addition, in order to positively treat the generated gas, it has been attempted to install a gas treatment device on top of all the existing gas vent pipes or to newly install a gas vent well, but this is very difficult. Costly and time consuming.

[0004]

The present invention was developed in order to solve the above-mentioned problems, and the waste landfill disposal site according to claim 1 has a pipe for collecting and distributing leachate at the bottom. Along with communicating the lower end to the water collection and distribution pipe, the upper end is open to the atmosphere, a gas vent pipe having a gas flow port on the peripheral wall is erected from the water collection and distribution pipe, and a gas suction means that communicates with the water collection and distribution pipe of the leachate is provided, A gas treatment means for treating the gas sucked by the gas suction means is additionally provided. In this case, a means for adjusting the amount of inflow of air is provided near the upper end of the gas vent pipe, or on the peripheral wall of the portion of the gas vent pipe that contacts the atmosphere,
It is preferable to provide a shielding means for shielding the gas flow port. The gas collection device at the waste landfill disposal site according to claim 4 is constructed such that the lower end of the leachate collection and distribution pipe laid at the bottom of the waste landfill disposal site is communicated with the collection and distribution pipe, and the upper end is the atmosphere. In a gas collection device at a waste landfill disposal site, which is provided with a gas vent pipe having a gas flow port on its peripheral wall, a gas suction means communicating with the collection and distribution pipe of the leachate is provided. . Further, the gas treatment device at the waste disposal site according to claim 7 is constructed such that the lower end of the leachate collection and distribution pipe laid at the bottom of the waste landfill disposal site and the lower end of the collection and distribution pipe communicate with each other. A gas treatment device in a waste landfill disposal site, comprising: a gas vent pipe that is open to the atmosphere and has a gas flow port on its peripheral wall; and a gas suction means that communicates with a water collection and distribution pipe for leachate. It is characterized in that the gas sucked in is supplied to the gas processing means. Further, both the gas collecting apparatus at the waste disposal site according to claim 4 and the gas processing device at the waste disposal site according to claim 7 are provided with air inflow amount adjusting means near the upper end of the gas vent pipe. It is preferable to provide a shielding means for blocking the gas flow port on the peripheral wall of the portion of the gas vent pipe which is in contact with the atmosphere.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION In the illustrated embodiment, 10 is a vast landfill disposal site constructed by digging deep into the ground to form a recessed portion, the inner circumference and bottom of which are well known in the recessed portion. It is covered with a water impermeable sheet to prevent the leachate from penetrating into the ground and contaminating the groundwater. Further, at the bottom of the concave portion, a water collecting and distributing pipe 11 for draining the leachate generated from the discarded waste to a storage tank 12 outside the site is provided like a mesh. In the portion of the water collection and distribution pipe 11 which is piped in the concave portion, a water passage opening for taking in the leachate into the pipe is formed in the peripheral wall.

A gas vent pipe 13 having a lower end communicating with the water collection and distribution pipe is erected at various places of the water collection and distribution pipe 11 which are arranged in the concave portion. The upper end of the gas vent pipe 13 is open, and the peripheral wall has a gas flow port for taking in the gas generated from the waste A discarded in the concave portion. When the height of the waste layer dumped in the concave portion approaches the upper end of the degassing pipe 13, a new degassing pipe is spliced and extended upward, and the upper end is always located above the upper surface of the waste layer. Let

The leachate collected in the storage tank 12 is pumped by the pump P ₁
The water is sent to the leachate treatment facility to make it harmless and then discharged.

In addition, an air supply pipe 14 is provided in the gas phase portion of the storage tank 12.
Is open at one end. A fan F is provided in the air supply pipe 14 as a gas suction means, and the other end of the air supply pipe 14 is connected to the gas processing means 15. The gas generated in the layer of the landfill waste put into the concave portion of the disposal site by the operation of the fan F enters the inside of the gas vent pipe 13 from the gas circulation port of the peripheral wall and flows downward to collect the leachate. It is guided to the storage tank 12 through the inside of the water pipe 11, and the gas treatment means 15 is connected to the gas supply pipe 14 by the gas supply pipe 14.
Sent to and processed there.

The gas treatment by the gas treatment means 15 may be a general gas treatment, for example, water washing, alkali washing, acid washing, alkali + sodium hypochlorite washing, acid washing + alkali washing, acid washing + ( It is an alkali + sodium hypochlorite cleaning), activated carbon adsorption, biological deodorization (including blowing into the aeration tank for water treatment), desulfurization tower, etc., and is selected according to the properties of the generated gas. This gas treatment may be performed collectively at the leachate treatment plant.

Since all the upper ends of the gas vent pipes are open to the atmosphere, it is preferable to provide a facility such as a damper for adjusting the opening degree to all the vent ports to control the inflow of air. . This is because air and the generated gas are efficiently sucked from all the gas vent pipes, and the landfill waste is kept anaerobic and aerobic, which promotes decomposition and generation of hydrogen sulfide and the like due to anaerobic fermentation. This is to suppress it. Therefore, the damper 16 or the like is adjusted so as to suck some air from all the gas vent pipes. A flow meter may be attached to each gas vent pipe. If possible in this way, it is desirable that the oxygen concentration at each connection point between the gas vent pipe and the water collection and distribution pipe is 15% or more.

As the gas vent pipe, one having a gas flow port on the peripheral wall is used, but the portion above the landfill waste layer near the opening is covered with a cover 17 so that the gas flow port on the side of the gas vent pipe is provided. Temporary shielding is desirable for efficient gas suction. In addition, the water collection and distribution pipes that normally have water passages on the peripheral wall are also used, but if waste is not piled up on the water collection and distribution pipe at the bottom of the recess at the beginning of landfill, temporary shielding will be performed for the same reason. Is desirable. However, these shields should be removed immediately before they are buried in the landfill so as not to interfere with the original functions of the gas vent pipe and the water collection and distribution pipe.

In particular, as described above, the gas vent pipe is extended upward as the volume of the landfill becomes higher. Therefore, a gas flow port shield and an air inflow adjusting device such as a damper are easily installed. , It is desirable to be able to remove it.

In the embodiment of FIG. 1, the leachate storage tank 12 has a closed structure to prevent gas from leaking out from the storage tank, but the upper surface of the storage tank is open as in the embodiment of FIG. You may have. In this case, the terminal 11 'of the water collection and distribution pipe that introduces the leachate into the storage tank is immersed in the liquid of the leachate in the storage tank to prevent the gas from flowing out of the storage tank, and the inside of the water collection and distribution pipe is closed. The gas sucked in is the air pipe 1 connected to the water collection and distribution pipe.
4 to the gas processing means 15.

The waste landfill disposal site has been described by taking the case where the earth is dug down as an example. However, it may be constructed by forming a valley in a mountain, or a soil weir wall and a concrete side wall are provided on a flat land. You may form it. Further, the present invention can be applied to an existing disposal site and a new disposal site.

[0015]

EFFECTS OF THE INVENTION According to the present invention, a gas containing a malodorous, flammable, toxic, and global warming substance generated from a waste landfill site is connected to a gas vent pipe from the end of a water collection and distribution pipe such as a fan. By sucking with the suction means and processing with the gas processing means, it is possible to effectively improve the environment without diffusing the generated gas to the surroundings. Further, since gas treatment is performed at one place of the collection end point of the collection and distribution pipes (inlet of the waste water storage tank), it is more efficient than the method of installing a treatment device in all the gas vent pipes or installing a gas vent well At the same time, if gas problems become apparent after the operation of the landfill site facility, it is easy to add more.

[Brief description of drawings]

FIG. 1 is a flow sheet of an embodiment of a waste landfill disposal site, a gas collecting apparatus and a gas processing apparatus therefor according to the present invention.

FIG. 2 is a flow sheet of a waste landfill disposal site according to the present invention, and a gas collecting apparatus and gas processing apparatus therefor according to another embodiment.

[Explanation of symbols]

10 Waste landfill disposal site 11 Leachate collection and distribution pipe 12 Leachate storage tank 13 Venting tube 14 Air pipe 15 Gas processing means 16 damper 17 Shielding cover

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Yasuhiko Ishii             Kurita, 3-4-3 Nishi-Shinjuku, Shinjuku-ku, Tokyo             Industry Co., Ltd. F-term (reference) 4D004 AC07 BB03 CA12 CB50

Claims (9)

[Claims] 1. A leachate collection and distribution pipe is laid at the bottom of the waste landfill site, and the lower end is connected to the collection and distribution pipe,
A gas vent pipe having an upper end opening to the atmosphere and having a gas flow port on the peripheral wall is erected from the water collection and distribution pipe, and a gas suction means communicating with the water collection and distribution pipe of the leachate is provided to remove the gas sucked by the gas suction means. A waste landfill site characterized by being equipped with a gas processing means for processing. 2. The waste landfill disposal site according to claim 1, further comprising air inflow control means provided near the upper end of the gas vent pipe. 3. The waste landfill disposal site according to any one of claims 1 and 2, wherein a shielding means for shielding the gas flow port is provided on a peripheral wall of a portion of the gas vent pipe which is in contact with the atmosphere. A characteristic waste landfill site. 4. A collection and distribution pipe for leachate laid at the bottom of a waste landfill site and a lower end communicating with the collection and distribution pipe, the upper end opens to the atmosphere, and the peripheral wall has a gas flow port. A gas collecting device in a waste landfill disposal site, comprising a gas suction means in communication with the water collection and distribution pipe of the leachate in the waste landfill disposal site. 5. The waste gas landfill disposal facility according to claim 4, further comprising air inflow control means provided near the upper end of the gas vent pipe. Gas collector in the field. 6. The gas collecting apparatus for a landfill disposal site according to claim 4, wherein a shielding means is provided on a peripheral wall of a portion of the degassing pipe which is in contact with the atmosphere for shutting off a gas flow port. A gas collection device at a waste landfill disposal site. 7. A collection and distribution pipe for leachate laid at the bottom of a waste landfill site and a lower end communicating with the collection and distribution pipe, the upper end of which is open to the atmosphere, and the peripheral wall has a gas flow port. A gas treatment device at a waste landfill disposal site comprising a gas vent pipe and a gas suction means communicating with a collection and distribution pipe for leachate, wherein the gas sucked by the gas suction means is supplied to the gas treatment means. Gas treatment equipment at a waste landfill disposal site. 8. The gas landfill disposal facility according to claim 7, further comprising air inflow control means near the upper end of the gas vent pipe. On-site gas treatment equipment. 9. The gas treatment apparatus for a waste landfill according to claim 7, further comprising a shielding means for shielding a gas flow port on a peripheral wall of a portion of the gas vent pipe which is in contact with the atmosphere. A gas treatment device at a waste landfill site characterized by being provided.