What issues need attention in disposal well?
Disposal well is a relatively technical one. For reinjection well, it will be affected by the environment by separating pumping well from reinjection well.
The well completion design process, construction method and layout are adopted for the reinjection well.
The difference between the well completion is to increase the disposal well diameter (ф 700mm) and the length of Johnson well screen pipe. Because the stratum has a strong permeability coefficient under 13m, and the higher the pressure head, the smaller the pressure head.
Considering that the heat exchange rate of disposal well can give full play to the balance of groundwater temperature field in the same year and environmental impact, the principle of separation of pumping well and disposal well is adopted.
Sand treatment method
As for sand and gravel control, as long as the well construction standard is strictly controlled in the well construction, the standard of sand content in the test well is 1 / 200,000.
The gravel in the water source system can be ignored. However, in order to protect the service life of the water well system and the system equipment, a wedge wire Y-type filter is installed before the well water inlet plate heat exchanger inlet pipe.
(We are a brand manufacturer of wedge mesh filters in China. In addition to Johnson well screen, we can also provide customized services for wedge mesh filters for customers worldwide.)
According to the provided pumping well report, see why the quality of groundwater is water, and the pH is 7.1, which is neutral water. It has a hardness of 9.72 milligram equivalents / liter and is extremely hard water. CL- + SO42- is 59.9 mg / L. It is weakly corrosive to steel pipe structure, and it is easy to make the system scale.
Reinjection wells can increase groundwater resources. Control and raise the groundwater level to prevent the deterioration of water quality due to the significant decrease of groundwater level. Now it has a good development prospect.
Injection well Vs dewatering well
- Injection well points: Wells that inject and dispose of corrosive or harmful liquids.
- Dewatering well point: Refers to the small well that clears the water in the mine tunnel or stope.
- Recharge well point: only pumping and not irrigating, not only is not conducive to protecting geothermal resources, but also will infiltrate underground water bodies with geothermal water brands containing certain harmful ingredients, causing different levels of environmental chemical pollution.
Some drainage temperatures exceed environmental regulations and cause thermal pollution. Therefore, recharge mining is regarded as an important measure for sustainable geothermal development.
- Dewatering well point: in the process of mining, there is a drainage system of underground tunnel that can be used, so that the water in the stope or tunnel is led into the dewatering well at a certain distance along the ditch, flows into the water bin through the underground tunnel connected with the dewatering well, and then is discharged to the ground by the water pump through the special drainage well or directly flows out of the ground by the drainage tunnel.