JPS5937367B2 - Waste landfill method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION This invention is a waste landfill method, in particular, covers the upper part of the landfill site to prevent rainwater from penetrating, and at the same time, it aerates the organic matter in the waste by introducing too much air into the landfill site. Concerning a waste landfill method that promotes decomposition.

The methods of processing and disposing of municipal waste can be roughly divided into three methods: composting for reuse or resource recovery, methods that perform intermediate treatment such as incineration, crushing, and compression, and then dispose of it in a landfill, and methods that dispose of it in a landfill without treatment. It is divided into different methods.

Of this amount, the amount that is disposed of in landfills without treatment is estimated to be about 40 to 50 times the amount of waste generated.

Conventionally, one of the following methods has been adopted to dispose of waste in a landfill without treatment.

In other words, there are so-called anaerobic landfills in which waste is simply dumped in a concavely formed landfill site, and so-called anaerobic landfills in which waste, covered soil, waste, and covered soil are repeatedly formed in a concavely formed landfill site. Anaerobic sanitary landfill, in which an impermeable layer is formed at the bottom of the concave landfill site and a drainage pipe is provided, and layers of waste and covering soil are alternately formed on this, similar to the anaerobic sanitary landfill. These include so-called improved sanitary landfills, semi-aerobic landfills, and the most effective aerobic landfills.

However, according to these methods, the amount of liquid leached from the landfill site increases due to the influence of rainwater that permeates into the landfill site, and the quality of the water is contaminated by leachate from organic matter contained in the waste. As a result, it has become a source of secondary pollution around the landfill site.

Currently, in order to treat such leachate, an excessively large treatment facility is required at the landfill site.

Furthermore, the decomposition of waste is easily affected by changes in temperature and may not be sufficient in some cases.

The inventors completed this invention, which eliminates the drawbacks of the conventional waste physics legislation, while researching the prevention of secondary pollution to the environment by leachates from waste landfill sites.

Therefore, the purpose of this invention is to prevent wastewater from flowing out from a landfill site to the surrounding area, and the purpose of this invention is to promote aerobic decomposition of organic matter contained in waste. A further object of the present invention is to purify undecomposed sewage contained in waste, and a further object of the invention is to prevent volatilization of malodorous components and scattering and leakage of waste. Another object of the present invention is to prevent sewage odor pollution in landfills with extremely simple equipment.

That is, in the present invention, as in the illustrated embodiment, the upper part of a landfill site 2 whose side and bottom parts are formed with an impermeable layer 1,
A landfill site 2 is covered with a covering material 3 made of an impermeable material.
A waste product characterized by preventing rainwater from penetrating into the waste material, and by introducing air into the waste layer 4 of the landfill site 2 to aerobically decompose organic matter contained in the waste material. In addition to making the landfill construction method a specified invention, the upper part of the landfill site 2 whose sides and bottom are formed with an impermeable layer 1 is covered with a coating made of an impermeable material to allow rainwater to permeate into the landfill site 2. At the same time, air is introduced into the waste layer 4 of the landfill site 2 to aerobically decompose the organic matter contained in the waste, and at the same time the coating is expanded upward by the air pressure. The first combined invention is a waste landfill construction method characterized by to prevent rainwater from penetrating into the landfill site 2, and to aerobically decompose organic matter contained in the waste by introducing air into the waste layer 4 of the landfill site 2, The leachate generated from the organic matter due to this decomposition is recirculated to the landfill site 2 and purified by a watering hearth method using the waste layer 4 as a furnace material, thereby simultaneously performing waste decomposition and wastewater treatment. A waste landfill construction method characterized by the following is provided as a second combined invention.

Next, the present invention will be explained based on illustrated embodiments.

An impermeable layer 1 is formed on the sides and bottom of the landfill site 2.

The impermeable layer 1 is made of rubber, synthetic resin, asphalt, concrete, etc., which is impermeable to water, has corrosion resistance, and has sufficient strength.

Thereby, the landfill site 2 and the outside of the impermeable layer 1 are cut off.

The upper part of the landfill site 2 is covered with a covering material 3 made of a water-impermeable material.

The covering material 3 may have any structure as long as it prevents rainwater from entering the landfill site 2, but in this embodiment, a covering material was used.

Although the coating is not particularly shown, it is formed by joining together a large number of unit membranes each having a relatively small area.

Therefore, a coating suitable for the area and shape of the landfill site 2 can be formed.

A reinforcing rope is sewn around the unit membrane, and the reinforcing rope has metal fittings for connection.

The membrane 3' is assembled by overlapping the circumferences of each unit membrane and tightening the metal fittings with bolts.

Although the connection is made by bolts, the peripheral parts of the unit membranes overlap, so if each membrane is tensioned by air pressure as described later, the shielding performance between the inside and outside will be good.

A water collection pipe 5 and an air supply pipe 6 are arranged along the bottom of the landfill site 2, and the water collection pipe 5 is connected to an external water collection pit 7, and the air supply pipe 6 is connected to a blower 8. Then, air is sent into the landfill site 2 from the air supply pipe 6, and the liquid in the landfill site 2 collects in the water collection pipe 5 and flows into the water collection pit 7.
sent to.

4 is a waste layer, which is alternately laminated with the soil cover layer 9.

A leachate sprinkler 10 is provided between the upper surface of the landfill site 2 and each coating, and is connected to a submersible pump 11 in the water collection pit 7 by a water pipe 12.

13 is a dam, and a rainwater storage tank 14 is located behind the water collection pit 7 in FIG.

In this way, the coating 3' and the impermeable layer 1 prevent rainwater from penetrating into the landfill site 2, and air is fed into the landfill site 2 through the air supply pipe 6 by the blower 8.

Air passes through the laminated waste layer 4 and soil covering layer 9, exits to the upper blade of the landfill site 2, and expands the coating upward.

The air comes into contact with the waste and the organic matter contained in the waste is decomposed under aerobic conditions.

This decomposition is mainly thought to occur in two ways: by aerobic bacteria and by oxidation.

The leachate produced by the decomposition of organic matter has a higher biochemical oxygen demand (BOD) and chemical oxygen demand (CDO) than the leachate produced from an anaerobic landfill such as the conventional example.
, ammonia nitrogen (NH4+-N) and other water quality evaluation indicators are improved.

The air passing through the landfill site 2 and coming out upwards fills up and expands the coating upwards.

When the coating 3' is tensioned, the polymerized portions of the unit membranes that constitute the coating are bonded together by the pressure of the internal air, so that the shielding properties between the inside and the outside of the coating are improved.

However, if the coating 3' seals the upper part of the landfill site 2, the internal air pressure will become excessive and the air supply from the air supply pipe 6 will stop, or the coating 3' will rupture. ' is provided with a gap to allow air leakage and prevent rainwater from entering.

In the case of the coating 3' of this embodiment, air leaks from the overlapping portions of the individual membranes constituting it.

If an amount of air corresponding to this amount of leakage is sent from the air supply pipe 6, air will be supplied into the landfill site 2 while maintaining a constant pressure inside the coating 3', thereby achieving aerobic conditions. , coating 3'
expansion is ensured.

The inflated state can be maintained if the pressure difference between the inside and outside of the coating 3' is about 10 to 30 mmAq.

The coating 3' can also have a double structure to prevent the temperature of the landfill site 2 from decreasing in winter.

This is to prevent a decrease in the decomposition rate of organic matter due to a drop in temperature.

Further, without using the coating 3' for the covering material 3, a roof having a fixed shape such as a kamabot-shaped roof or the like may be used.

In that case, it goes without saying that it is not necessary to maintain the shape of the covering material 3 using the injected air pressure, but the structure must be such that it prevents rainwater from entering and allows the injected air to leak appropriately. is required.

As described above, the leachate produced by the decomposition of organic matter under aerobic conditions is mainly composed of water, but still contains undecomposed sap.

This water is introduced from the bottom of the landfill site 2 through a water collection pipe 5 into a water collection pit 7.

The leachate collected in the pit 7 is sent to the landfill site 2 from the leachate sprinkler 10 via the connecting pipe 12 by the submersible pump 11.
is recirculated to

Here, the leachate is oxidized and purified by a forced watering hearth method using the waste layer 4 and the soil cover layer 9 as furnace materials, and introduced from the bottom through the water collection pipe 5 into the water collection pit 7 in the same manner as described above. Recirculated from the water sprinkler 10 to the landfill site 2,
The exudate is purified by such repetition.

This forced watering hearth system improves the biochemical oxygen demand (BOD), chemical oxygen demand (COD),
If the ammonia nitrogen (NH40N) etc. meet the standard values set by law, the leachate will be purified and can be discharged.

Therefore, there is no need to separately provide a treatment facility for the leachate, but even if it is necessary, the treatment facility can be small because the purification rate is high.

This purification is achieved by the formation of a tear film of aerobic microorganisms on the surface of the furnace material when the leachate passes through the landfill site 2, which comes into contact with the leachate to remove colloidal substances and dissolved substances from the leachate. be purified.

In order to maintain the aerobic condition of the furnace material, it is necessary to supply a sufficient amount of oxygen, and this oxygen supply can be effectively achieved by forcing air upward from the air supply pipe 6.

Therefore, the air supplied from the air supply pipe contributes to promoting the decomposition of organic matter in the waste, promoting purification of the leachate, and simplifying the structure of the coating material 3 by expanding the coating 3'.

The landfill site 2 is surrounded by a coating 3' and other covering materials 3 and an impermeable layer 1, and there is no permeation of water from the outside. If the water required to keep the decomposition of Suitable moisture can be obtained by sprinkling water on the landfill site.

When the aerobic decomposition of the organic matter is completed, there will be no leaching of liquid from the waste or generation of bad odors, so the covering material 3 will be removed and the landfill site 2 will be used for multiple purposes as a landfill. can be provided.

In addition, when the coating 3' is used as described above for the coating material 3, it is sufficient to attach the coating 3' around the landfill site 2, which makes the equipment and removal easy, and the Easy to store.

Furthermore, if the membrane surface is damaged or aged, it can be partially replaced, repaired, or relocated, making maintenance and storage easier.

As is clear from the above, according to the present invention, since the sides, bottom and upper part of the landfill site 2 are surrounded by impermeable materials, there is no possibility that leachate will overflow and leak into the surrounding area. , it does not cause pollution of lakes and marshes, and prevents the scattering and outflow of waste and bad odors.In addition, by introducing air and circulating leachate, it is possible to aerobically decompose organic matter contained in waste. Furthermore, the leachate generated from the waste can be purified simply by circulating it.

Therefore, there is a significant effect that waste can be treated very effectively in a short period of time without causing environmental pollution.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, and FIG. 1 is a longitudinal sectional view, and FIG. 2 is a sectional view taken along the line A--A in FIG. 1. In the figure, 1 is an impermeable layer, 2 is a landfill site, 3 is a covering material, 3' is a coating, and 4 is a waste layer.

Claims (1)

[Scope of Claims] 1. The upper part of a landfill site whose sides and bottom are formed with an impermeable layer is covered with a covering material made of an impermeable material to prevent rainwater from penetrating into the landfill site, and A waste air physical construction method characterized by introducing air into the waste layer of the landfill site to aerobically decompose organic matter contained in the waste. 2. The upper part of the landfill site, which has an impermeable layer on the sides and bottom, is covered with a film made of an impermeable material to prevent rainwater from penetrating into the landfill site, and to prevent the waste on the list of landfill disposal sites from entering the landfill site. A waste landfill method characterized in that air is introduced into the layer to aerobically decompose organic matter contained in the waste, and at the same time the coating is expanded upward by the air pressure. 3. The upper part of a landfill site with an impermeable layer on the sides and bottom is covered with a covering material made of an impermeable material to prevent rainwater from penetrating into the landfill site, and to prevent the disposal of the landfill site. A water sprinkler furnace that uses the waste layer as the furnace material by introducing too much air into the material layer to decompose the organic matter contained in the waste, and by recirculating the leachate produced from the organic matter to the landfill site. A waste landfill method that uses a bed method to purify waste and performs aerobic decomposition of waste and wastewater treatment at the same time.