JPH035532A - Settling basin for ground-water utilizing system - Google Patents

Abstract

PURPOSE:To effectively utilize a settling basin by a method wherein a water disposing means containing removal of sludge, a snow melting disposing means, and an environmental protection means are built in the settling basin built under a ground. CONSTITUTION:An underground dam 1 having a cut-off wall 1a, an intake well 2, a cultivating well 3, and a settling basin 4 are built. Snow collected from an urban district during snow fall is charged in a snow melting disposing part 4a, and underground water is caused to flow to a heat exchanger 5 to melt snow. Water is caused to flow through a flow straightening wall 4e to a settling tank 4b, sludge is removed, and the water is injected in a cultivating well 3 togetherwith water from a heat exchanger 5. Rainwater during a rainy season is also purified in the settling tank part 4b to inject the water in the cultivating well 3. During a dry season, an aerating device 8 and a ventilating blower 10 are operated to cause ground-water to flow to an exchanger 5 for air conditioning, and mushrooms are cultivated. This constitution effectively utilizes the settling basin.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention is incorporated into a groundwater utilization system that utilizes groundwater stored in an underground dam as a cold source, and temporarily stores snowmelt water and rainwater collected on the ground side. , relates to a settling basin that removes mud and sand and then injects it into an underground dam to cultivate groundwater.

[Conventional technology]

Researchers have proposed a groundwater utilization system, mainly aimed at areas with heavy snowfall, that utilizes underground aquifers in the area to create subterranean dams, and uses the groundwater stored in these dams as a cold source for various purposes above ground. For example, the magazine "Water J" July 1987 issue "Snowmelting is an attempt at water utilization - combining it with groundwater"
(Author: Koji Fukami), 1985 Research and Development Committee Study Subcommittee Report published by the Engineering Promotion Association.
This is reported in Chapter 3: Long-term storage of local energy (cold heat from snow) using underground dams.

In other words, underground aquifers in areas with heavy snowfall contain naturally nourished groundwater (7
There is plenty of cold water (~14°C) stored. Therefore, in the above-mentioned groundwater utilization system, an underground dam is built in the area to utilize the groundwater stored in the underground aquifer as a water resource. It is used for air conditioning in buildings, mushroom cultivation, and low-temperature rice warehouses, etc. In addition, when it snows in winter, groundwater is channeled to the roofs of buildings, city streets, or specific snow collection plazas for use in melting snow, and throughout the year. Groundwater is used as cooling water for waste treatment and power generation plants in the area.

On the other hand, when viewed throughout the year, the amount of water in underground dams increases during the early spring snowmelt and rainy seasons, but at other times, the natural vortexing of groundwater decreases. Therefore, the above-mentioned research report also mentions the necessity of artificial vortex cultivation, which is used to pump up water from underground dams, recover water used above ground, and return it to the underground dam when operating a groundwater utilization system. When artificially cultivating a subsurface dam, in order to prevent clogging of the vortex feeding well with mud and sand, water collected on the surface side is led to a sedimentation pond to remove mud and sand, and then the water is pumped through the recharge well. It also mentions the need for injection into underground dams.

[Problems to be Solved by the Invention] By the way, when a sedimentation pond is combined with a groundwater utilization system and put into practical operation as described above, there remain some problems to be solved. In other words, (1) When snow that has fallen in the urban areas of a region is melted by pouring it into drains, etc., a large sedimentation pond is created downstream of the snow, and from the sedimentation pond, a vortex well is scattered throughout the region. A water transmission system up to 100m is required, which requires a costly investment in public facilities.

(2) Furthermore, even if a large sedimentation pond is installed in the area to treat snowmelt water, it will only be used for snowmelt treatment during the winter season, and the equipment will be idle the rest of the year. Efficiency is low.

The present invention has been made in consideration of the above points, and relates to a sedimentation pond used for artificial recharge of groundwater in combination with the above-mentioned groundwater utilization system, which not only collects and processes snowmelt water, but also
The investment will be made to function as a water retention pond to prevent urban flooding that occurs during the rainy season, and will also be configured to allow the sedimentation pond to be used for, for example, mushroom cultivation during the dry season, excluding periods of snow and rain. The purpose is to provide a multi-purpose sedimentation basin with improved efficiency.

[Means for Solving the Problems] In order to solve the above problems, in the sedimentation tank according to the present invention,
A water treatment method in which a sedimentation tank is constructed underground on the surface side, and includes mud and sand removal as ancillary equipment.

In addition to a snow melting means that uses groundwater to melt snow collected in a sedimentation pond, it shall also be constructed with an environmental conservation means to maintain the internal space of the sedimentation pond in an environment suitable for plant cultivation during periods of dry water. do.

[Effect]

With the above configuration, the settling pond is constructed underground using parks, vacant lots, etc. in the area. In addition, the water treatment means provided as ancillary equipment to the sedimentation pond are a mud discharge pump and an aeration device to prevent the water from becoming anaerobic and emitting a sewage odor during storage, and the snow melting treatment means is an underground dam. This is a snow melting heat exchanger that melts snow collected in a sedimentation basin using water pumped up from the sedimentation basin (approximately 14℃) as a heat source.Furthermore, as an environmental protection measure, a ventilation system and lighting windows are installed inside the sedimentation basin. ing.

With this configuration, during the winter snowfall (December to March), snow collected from roads in the city is transported to the sedimentation pond and thrown into the sedimentation pond, where the snow melting equipment is operated to melt the snow. Lend. In addition, mud and sand are separated from snowmelt water while it is stored in a sedimentation pond, and the water after sedimentation treatment is injected into a feeding well that leads to an underground dam. In addition, rainwater that temporarily overflows the sewer system due to heavy rains during the rainy season (June to September) is similarly collected in a settling pond, where the mud and sand are removed, and the treated water is passed through a vortex well to an underground dam. artificially recharged. Furthermore, the internal space of the sedimentation basin is empty during the dry season (excluding snowfall and rain showers), so ventilation, lighting, and air conditioning using the snow melting heat exchanger described above are used to remove sedimentation. The interior space of the pond will be maintained in an environment suitable for plant cultivation (including a working environment for humans), and will be used for cultivation of mushrooms, etc., and breeding of seeds and seedlings using biotechnology. This will allow the sedimentation pond to operate for multiple purposes throughout the year.

(Embodiment) FIGS. 1 and 2 are configuration diagrams of different embodiments of the present invention.

In the figure, 1 is an underground dam made by installing an impermeable wall 1a in an underground aquifer, 2.3 is an intake well and a recharge well that are connected to the underground dam 1, and 4 is a settling pond according to the present invention. The sedimentation pond 4 is constructed underground using parks, vacant lots, etc. in the area.

Here, the inside of the sedimentation tank 4 is a snow melting treatment tank section 4a.

It is divided into a settling tank section 4b and a water storage tank section 4c, and a hopper 4d into which snow collected and transported from the city is placed is opened on the top surface of the snow melting processing tank section 4a, and a hopper 4d is opened in the tank. Heat exchanger for snow melting as snow melting processing means 5. A stirrer 6 is installed. In addition, the sedimentation part 4b includes a mud pump 7 disposed on the bottom side as a water treatment means for discharging mud and sand, and an aeration system that combines an air supply blower 8a and an air diffuser plate 8b! 8, and a lighting window 9 installed in the ceiling wall as an environmental protection measure. and a ventilation blower 10. In addition, 11 is connected to the discharge side of the ventilation blower 10, and is, for example, an ozone treatment type deodorizer.

On the other hand, the water intake well 2 is equipped with a water intake pump I2, and the groundwater pumped up by the pump 12 is distributed to various places in the area as a cold water source as described above, and also as a heat exchanger for snow melting. Water is supplied to vessel 5. In addition, the outflow water from the snow melting heat exchanger 5 is combined with the return water of the groundwater used in the area.
The water stored in the water tank section 4c is piped so as to be injected into the underground dam 1 through the water well 3, and these constitute a groundwater utilization system including the settling pond 4.

With the configuration of such a groundwater utilization system, the cold water stored in the underground dam l is used for various purposes within the region throughout the year. In addition, during snowfall in winter, snow collected and transported from urban areas etc. is thrown into the snow melting treatment tank 4a through the hopper 4d of the sedimentation tank 4, where groundwater (water temperature of about 14°C) is poured into the heat exchanger 5. to melt the snow. In this case, water is stirred by the stirrer 6 to promote snow melting. Also,
The snowmelt water passes through the flow straightening wall 4e to the sedimentation seed section 4b, where the mud and sand are removed, and then overflows to the water storage tank section 4c, where it joins with the water from the snowmelting heat exchanger 5 and flows into the cultivation well 3. injected into. Note that the mud and sand accumulated at the bottom of the precipitate seed section 4b are appropriately discharged to the outside by the mud and sand pump 7.

Further, in order to promote sedimentation of mud and sand, a flocculating agent is added as necessary.

On the other hand, snowmelt water outside the settling basin and rainwater overflowing from sewers due to heavy rain during the rainy season also flow into the settling basin 4 and are collected, and after being purified in the settling tank 4b, it is passed through the water storage tank 4c. Injected into recharge well 3. In addition, if rainwater collected in the sedimentation pond 4 during periods of high temperature remains for a long time,
The water becomes anaerobic and gives off a sewage odor, so to prevent this, an aeration device 8 and a ventilation blower 10.
The deodorizer 11 is operated appropriately to prevent foul odor pollution from being caused to the surrounding area.

Furthermore, during periods of drought (excluding snowfall and rainy seasons), settling ponds 4
There is no water collection, and the internal space is almost empty.

Therefore, during this period, the aeration device 8° ventilation blower 10 is operated to introduce fresh outside air into the internal space, and if necessary, ground water is flowed into the snow melting heat exchanger 5 for air conditioning, and the lighting window 9 is turned on. is taken in to maintain the internal space of the sedimentation pond 1 in an environment suitable for various operations including human operations, and in this environment, for example, cultivation of mushrooms and seedlings are carried out. In addition, during this period, stones,
By mounding up the soil and taking advantage of the suction effect of the soil and stones, you can also plant plants here and use it as a flower bed.

FIG. 2 shows an applied example, in which, compared to FIG. 1, the sedimentation tank 4 is constructed in an upper and lower two-stage structure, and the upper stage has a snow melting tank section 4a and a settling tank section 4b. In addition, a heat exchanger 5 for snow melting is provided at the opening of the snow charging hopper 4d, and above it, water taken from the water storage tank 4c is provided. A water sprinkling device 13 is additionally equipped to sprinkle water to assist snow melting.

Such a sedimentation tank with an upper and lower two-tiered structure requires less site area, and is advantageous as a sedimentation tank in urban areas where there is little open space.

〔Effect of the invention〕

The sedimentation basin according to the present invention is constructed as described above and exhibits an excellent effect.

In other words, for a sedimentation basin incorporated into a groundwater utilization system with the main purpose of artificial IT for a subterranean dam, the sedimentation basin is constructed underground on the surface side, and water treatment means including mixed waste removal are provided as ancillary equipment. .

In addition to snow melting means that uses groundwater to melt snow collected in sedimentation ponds, we have also provided environmental conservation means to maintain the internal space of sedimentation ponds in an environment suitable for plant cultivation during dry periods. 1) The snow that falls in the area is intensively melted in a settling pond,
Furthermore, after sand is removed, it can be injected into the subsurface dam from a nearby vortex feeding well, which eliminates the need for long water distribution pipes and simplifies the system.

(2) The same sedimentation pond can not only process snow melting, but also function as a water retention pond to prevent urban flooding by collecting large amounts of rainwater during the rainy season.

(3) Furthermore, during periods of drought, the internal space of the sedimentation basin can be utilized for plant cultivation under good environmental conditions, making it possible to operate the sedimentation basin throughout the year, increasing the efficiency of capital investment. can be improved.

[Brief explanation of the drawing]

FIGS. 1 and 2 are block diagrams of different embodiments of the present invention, respectively. In FIG. Mixing pump, 8: Aeration device, 9: Lighting window,
10: Ventilation blower.

Claims (1)

[Claims] 1) This is a sedimentation pond built into a groundwater utilization system that uses groundwater stored in an underground dam as a cold source. Snowmelt water and rainwater collected on the ground side are temporarily stored, mud and sand are removed, and then injected into the underground dam. In those that recharge groundwater by
The sedimentation basin is constructed underground on the surface side, and its auxiliary equipment includes water treatment means including mud and sand removal, and snow melting means that uses groundwater to melt snow collected in the sedimentation basin. A sedimentation pond of a groundwater utilization system characterized by being equipped with environmental protection means to maintain the internal space of the sedimentation basin in an environment suitable for plant cultivation.