JPH072305A - Disposal pit for industrial waste - Google Patents

Abstract

PURPOSE:To temporarily store the industrial waste difficult to be finally disposed in a storage pit similar to the final disposal pit so that the waste is extracted for disposal when it can be harmlessly disposed. CONSTITUTION:Corrosion-resistant metal cases 40 are arranged inside the throw-in tank of a disposal pit 33 made of cutoff type concrete and sealed with a deleterious waste liquid, and waste liquid discharge openings are provided on the upper faces of the metal cases 40. Since the corrosion-resistant metal cases 40 made of stainless steel or the like are arranged inside the throw-in tank, the disposal pit 33 can be easily molded when concrete is placed, no concrete corrosion occurs, and the waste liquid can be easily extracted and recovered from the opening sections of the metal cases 40 when the waste liquid disposal becomes technically feasible.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a waste treatment pit for enclosing a hazardous waste liquid, and more particularly to a pit structure that enables the waste liquid to be taken out after encapsulation and embedding.

[0002]

2. Description of the Related Art Increasing industrial waste has been of particular interest in recent years with regard to the safety of its final disposal site. The amount of industrial waste emitted during the course of various business activities is extremely large, and it is difficult to completely remove harmful substances even by various intermediate treatments. Safety is a problem.

Regarding the final disposal of such industrial waste,
Conventionally, standards for ensuring safety have been established in the national and local governments. For example, as shown in FIG. 5, a fence 2 is provided around a disposal site 1 and a standing bill 3 describing necessary display items is provided. A method such as landfilling the waste 4 is adopted.

FIG. 5 shows a barrier type disposal site using concrete pits. An internal partition 6 is provided in the barrier pit 5 made of concrete, and a concrete lid 7 is provided in the barrier pit 5 filled with waste. It is covered and sealed, and a roof 8 is provided in the pit 5 being dumped to prevent rainwater. In the disposal site using such a blocking pit 5, wastewater sludge, which is highly harmful, and incineration ash such as plastics are mainly buried. Although these have been subjected to intermediate treatment for detoxification, for example, plastic incineration ash has a technical difficulty for disposal, such as trace amounts of mercury and cadmium added as stabilizers and colorants. Many are accompanied.

The treatment pit according to the present invention performs a treatment similar to the final disposal, and as a result, has a structure similar to that of the barrier concrete pit.

[0006] However, looking at the conventionally proposed barrier type pits like this, none of them exceeds the administrative guidance standard. In other words, the conventional technique is only to increase the concrete thickness of the pit or to dispose a waterproof sheet on the inner wall surface of the pit (for example, Japanese Patent Laid-Open No. 59-59).
-136183), a more reliable and permanent technology has been disclosed that takes into consideration the possibility of waste material leakage in the event of a strong shock such as an earthquake, and long-term chemical changes of harmful substances. Absent. Therefore, the applicant has filed a patent application for a concrete pit that improves seismic resistance and reliably prevents leakage of harmful components (Japanese Patent Application No. 3-3).
50049).

[0007]

SUMMARY OF THE INVENTION The present invention is intended for storage of a waste liquid for a relatively long period of time until a detoxification treatment can be realized in the future, rather than a concrete pit of a blocking type for the final disposal of waste. It concerns processing pits. However, such a processing pit is of a type that has never been seen before.

As is well known, there are treatment standards of the national and local governments for industrial waste, and it is necessary to strictly comply with them. However, there are many types of waste, and conventionally there are long-term chemical changes and environmental impacts. Due to the lack of basic data, and the fact that there are still some fields for which no suitable detoxification method has been proposed, the pit structure is still being improved in terms of structure and material.

The waste liquid treatment according to the present invention is also the same. For those that can be rendered harmless through so-called intermediate treatment, appropriate final disposal such as burying and sealing in a barrier concrete pit is carried out, but sufficient detoxification treatment is performed. At present, some difficult things remain, and it is often difficult to take the form of final disposal (sealed burial → neglected).

Therefore, an object of the present invention is to temporarily store industrial waste such as waste liquid that is difficult to be finally disposed of in a storage pit similar to final disposal, and to take out the waste liquid when it can be detoxified. Is to

[0011]

In order to achieve the above object and achieve the object, the industrial waste treatment pit according to the present invention has a technical premise of a cut-off type treatment pit structure for enclosing a hazardous waste liquid. A corrosion-resistant metal case was arranged on the inner surface of the disposal tank of the processing pit made of concrete, and an opening for discharging the waste liquid was provided on the upper surface of the case body.

[0012]

The industrial waste treatment pit according to the present invention is technically premised on the construction of a blocking type treatment pit for enclosing the hazardous waste liquid, and by adding a means such as arranging a vibration-proof rubber in the concrete layer. It is possible to increase the strength such as earthquake resistance, and it is possible to have various variations in rigidity improvement.

Further, since a corrosion-resistant metal case such as stainless steel is arranged on the inner surface of the dumping tank, pit formation at the time of placing concrete is easy, but concrete erosion due to the waste liquid does not occur, and stable for a long time. Waste liquid can be stored. Since an opening for discharging the waste liquid is provided on the upper side surface of the case body, even if the lid is provided by placing concrete on the upper surface of the pit, there is a technical perspective on the waste liquid treatment when the waste liquid is taken out. The waste liquid can be easily collected from the opening of the metal case body.

[0014]

Embodiments of the present invention will be described below with reference to the accompanying drawings. 1 to 3 show an example of a processing pit according to the present invention, in which a crushed stone 30 is cut on a bottom floor surface of a landfill space excavated into a predetermined shape, and a waste concrete 31 is placed on the crushed stone 31.
To form a base, and the processing pit 33 is formed on the base. Reference numeral Q is a U-shaped side groove for discharging rainwater and the like.

The processing pit 33 is formed by placing a mold on the foundation 32 and pouring concrete. A stainless steel case 40 is arranged in each dump layer 34, and an elastic resin is formed in the concrete wall. Membrane material such as natural rubber sheet 3
Insert 6

The stainless case 40 is closely fitted to each of the dump layers 34, and has an opening 41 in a part thereof as shown in an enlarged view in FIG. The opening 41 has a cylindrical shape,
A screw thread 43 for screwing the cap 20 is provided on the upper end portion of the rising portion 42. Further, the bottom surface of the stainless steel case 40 is provided with an inclination 45 in order to eliminate the residual liquid when the waste liquid is taken out (during suction). Since it is expected that the suction hose will be inserted from the opening 41, it is desirable that the area immediately below the opening 41 be the deepest portion 46.

The natural rubber sheet 36 functions not only as a vibration absorbing material in the event of an earthquake, but also as a material for preventing leakage of harmful substances when a crack occurs in the concrete layer. To be installed. In this embodiment, it is disposed so as to be sandwiched between all the concrete layers including the partition walls 35 that define the respective dump tanks 34.

A natural rubber sheet 36 is provided on the outer wall 38 of the pit.
In addition to this, it is desirable to dispose a heat insulating panel, for example, a crosslinked foamed polyethylene panel (trade name Hiethylene S; Hitachi Chemical). This expanded polyethylene panel provides a heat insulating effect in the pit 33, prevents the chemical change of the waste liquid caused by the temperature change, and minimizes its progress. The primary cause of chemical changes is the effect of temperature changes that are sustained over a long period of time. Therefore, a heat insulation panel is provided so as to cover the entire outer periphery of the pit outer wall 38 including the entire outer periphery of the pit 33, if possible, the pit floor surface 37 and the lid 39, and the chemicals of the waste caused by the temperature change. Restrain change. When performing such heat insulation treatment, place a heat insulation panel also in the concrete layer that will be the lid,
It is desirable to keep the temperature inside the dump tank 34 constant.

The opening 41 of the stainless case 40 is sealed by the cap 20. This cap 20 is shown in FIG.
As shown in FIG.
A ring 22 is arranged to prevent the evaporative gas from leaking to the outside. The material of the disk 22 is, for example, stainless steel. An air spring 23 is attached to the center of the disk 22 to absorb the rise in the pressure inside the case due to the vaporized gas. The upper edge of the air spring 23 is supported by the stainless plate 24. This stainless plate 24
Is attached to the lower flat surface of the soft urethane resin 25 having a convex lens shape, and the soft urethane 25 has a function of absorbing the pressure from below by the air spring 23. Further, a hard urethane resin 26 is formed on the outer peripheral surface of the soft urethane 25.
A cap surface layer made of is provided. At the lower edge of the inner circumference of the hard urethane 26, a screw portion 27 that is screwed into the screw thread 43 is cut, so that the cap 20 is screwed into the screw thread 43 of the stainless steel case 40 to completely seal the opening 41. Stop. The air spring 23 has a rotatable intermediate expansion and contraction portion 29, and the O-ring 22 does not move even when the cap 20 is rotated.

According to the processing pit 33, since the stainless case 40 is arranged on the inner surface of the dumping tank, the pit formation at the time of pouring concrete is easy, but the concrete erosion due to the waste liquid does not occur, and the long-term stability is ensured. Then, the waste liquid can be stored. Further, since the opening 41 for discharging the waste liquid is provided on the upper side surface of the stainless steel case 40, even if the lid 39 is provided by placing concrete on the upper surface of the pit, it is easy to insert the suction hose into the opening 41 to take out the waste liquid. Can be collected at Moreover, since the bottom surface of the stainless steel case 40 is provided with the inclination 45, the remaining liquid can be almost completely recovered without remaining.

When the waste liquid is stored, the internal pressure of the case may increase to some extent due to the evaporated gas, but since the pressure is absorbed and attenuated by the air spring 23, the screw-sealed state of the cap 20 can be stably maintained for a long period of time. Since there is little data on the pressure change due to the type of waste liquid and the temperature environment at the beginning of implementation, it is desirable to insert a pressure gauge into the cap 20 so that it can be visually observed from the outside to monitor the change in the internal pressure.

Further, in this embodiment, since the natural rubber sheet 36 is arranged on the concrete wall portion, the earthquake resistance of the pit 33 is increased and the leakage of harmful waste liquid can be prevented. As a result of arranging the natural rubber sheet 36, the pit 33 has a structure that absorbs vibration shock and withstands an earthquake of magnitude 10. Further, since the heat insulating panel is arranged on the outer peripheral wall portion 38 of the pit 33, the chemical change of the waste liquid due to the temperature environment change of the buried place can be suppressed. The heat insulation panel also functions as a vibration absorber. Natural rubber sheet 36 and heat insulation panel 4
Since the resin-based film material such as 0 is lightweight and easy to handle, the entire pit 33 can be easily covered without any difficulty in working.

FIG. 6 shows another embodiment of the present invention. The stainless steel case 61 applied to the processing pit 60 is a case body having an open upper side. In this pit 60, a stainless steel case 61 is arranged in advance, a concrete lid body 62 is arranged in the ceiling portion, a natural rubber sheet 63 is arranged thereon, and an upper concrete layer 64 is further formed to seal the pit. . Then, valve openings 65v and 66v of a waste liquid injection pipe 65 and a waste liquid extraction pipe 66 are provided in a part of the upper concrete layer 64, and a roof 67 is provided at the valve openings 65v and 66v. The lower end of the take-out pipe 66 is arranged so as to reach the bottom of the stainless steel case 61. Reference numeral 68 is a swing stop at the tip of the pipe.

According to this structure, the structure of the pit is simpler than in the case where the cap is provided on the ceiling of the pit, and the pipes 65 and 66 arranged in advance simplify the work of injecting and removing the waste liquid.

Since the treatment pit according to the present invention is used for a purpose different from the concrete barrier type pit based on the conventional administrative guidance, the material of the pit is not necessarily limited to concrete. Acid, base,
Of course, other materials that can store and store cadmium and other harmful substances and can withstand chemical changes and prevent leakage can be used.

If more strict strength conditions are required, for example, as shown in FIG.
A lead plate, a stainless plate, or other metal panel 50 may be arranged, or a rigid panel such as FRP may be arranged to reinforce the entire pit.

In the above description including the embodiments,
Although the term "waste liquid" is used, it means a harmful liquid which has a bad influence on human body-environment. Hexavalent chromium waste liquid, P
In addition to waste liquid waste oil containing CB or cadmium, various liquids such as acid liquid and basic liquid are included. Among these, there are some that can be detoxified at the present time, but there is a limit in the capacity of the intermediate processing company, and in some cases immediate processing is difficult from the viewpoint of cost, so once the present invention is applied. In many cases, it is desired to store the waste liquid in the waste liquid treatment pit and perform the detoxification treatment at the stage where the conditions such as the technology, the cost and the like are satisfied.
Therefore, it should be understood that the application range of the treatment pit according to the present invention includes a harmful liquid which can be detoxified by the present technology. The liquid recovery period is assumed to span, for example, from January to about 10 years.

The cut-off pit according to the present invention is not limited in the number of dump tanks 34. The number of dump tanks 34 can be appropriately increased or decreased depending on the topography and environment of the treatment plant. In addition, the concrete thickness that defines the pit is 250k in accordance with the standard value of the barrier pit.
It is desirable that the wall thickness is 15 cm or more so as to have a compressive strength of g / cm ² or more. The pit shape, size, and definition are also free.

Regarding the inner wall surface of the dump tank 34, in addition to a corrosion-resistant metal case such as a stainless case, an appropriate waterproof sheet may be provided if necessary, or a waterproof resin such as FRP may be sprayed to improve the corrosion resistance. good. This also applies to the outer wall of the pit. However, regarding the treatment of the inner wall surface that contacts the waste liquid, the optimum material that does not show a chemical reaction is selected and used. In the present invention, since the metal case is closely joined to the inside of the pit, it is not only waterproof but also the rigidity itself of the pit against earth pressure or the like is improved.

The resin-based membrane material disposed inside the concrete layer exhibits good elasticity with respect to the set thickness of concrete,
Further, it is not limited to natural rubber as long as it can block moisture (or gas) accompanied by harmful substances. The film thickness is also free. Therefore, in addition to the sheet-shaped one, a panel-shaped film material may be used. Since this resin-based film material also has a vibration absorbing function, it is desirable that the concrete is cast as closely as possible so as not to separate from the concrete wall. Normal boltland cement may be used as the concrete, but when using special concrete or adding a mixture such as a hardening accelerator, etc., consider the compatibility with the resin-based membrane material and heat insulation material and use the resin-based sheet. Prevents deterioration and deterioration of panel function.

[0031]

As described above, in the waste liquid treatment pit according to the present invention, since the corrosion-resistant metal case such as stainless steel is arranged on the inner surface of the dumping tank, it is easy to form the pit at the time of placing concrete. Waste liquid can be stored stably for a long time without erosion of concrete due to waste liquid, while the waste liquid discharge opening is provided on the upper side of the case body, so waste liquid can be easily collected from the opening of the metal case body. You can do it. Therefore, for industrial waste such as waste liquid that is difficult to finally dispose of, store it in this pit once,
The waste liquid can be taken out and treated at the time when the detoxification treatment is possible.

[Brief description of drawings]

FIG. 1 is a side sectional view showing an example of a processing pit according to the present invention.

FIG. 2 is a plan view showing an example of a processing pit according to the present invention.

FIG. 3 is a sectional view showing a ceiling cap of a processing pit according to the present invention.

FIG. 4 is a diagram showing another configuration example of a processing pit according to the present invention.

FIG. 5 is a diagram showing a general example of a barrier-type final disposal site for industrial waste.

FIG. 6 is a sectional view showing another embodiment of the processing pit according to the present invention.

[Explanation of symbols]

 20 Cap 23 Spring 33, 60 Processing Pit 34 Disposal Layer 36, 63 Natural Rubber Sheet 40, 61 Stainless Steel Case 41 Stainless Steel Case Opening 45 Bottom Inclination

Claims (1)

[Claims] A cut-off processing pit for enclosing hazardous waste liquid, characterized in that a corrosion-resistant metal case is arranged on the inner surface of the disposal pit made of concrete, and an opening for discharging the waste liquid is provided on the upper side surface of the case body. Pit for industrial waste.