What are the technical points of drilling wells to find water?
What are the technical points of drilling wells to find water?
1. To study the local hydrogeological conditions in detail. If you don't understand hydrogeology, don't study hydrogeological conditions, only trust instruments, and measure points everywhere, it can only be called "blind measurement". Research can be conducted from the following three aspects.
1. Study topography and landforms. Topographic and geomorphic conditions determine the recharge, runoff and discharge conditions of groundwater, control the weathering of rocks, and affect the change of groundwater abundance and dryness. The watershed area is required for building a reservoir, and the replenishment area is required for drilling a well. The reason is the same. If the lithology conditions are the same, it is easier to form a well in a low-lying or favorable terrain. However, some small plains and depressions are often dominated by muddy rocks, which are easily weathered and eroded to form lowlands, and the groundwater is not good.
2. Study the water-richness of rocks. Rocks can be divided into three categories: igneous rocks, metamorphic rocks, and sedimentary rocks according to their genesis, and the subdivision is very complicated. No matter what the cause is, some feel "Gen" (rigid), some feel "cotton" (flexible), and some feel "brittle" (brittle) when struck with a hammer. Brittle rocks and soluble rocks such as limestone are more It is easy to become a well.
3. Study the crack development of rocks. Fissures are more developed near the fault fracture zone. Sloping rocks are more likely to develop fissures than horizontal rocks.
2. Choose a geophysical prospecting method suitable for the local geological conditions
At present, the method of geophysical prospecting for water is mainly electrical prospecting. Electric detection method is divided into artificial electric field method and natural (natural) electric field method. There are many specific methods, commonly used are double-connected electrical measurement method, high-density electrical measurement method, vertical electrical sounding method, quadrupole symmetrical section method, combined section method, induced polarization method, etc. Each method has its applicable conditions and conditions. Interference factors must be selected according to local conditions. After many years of water search research in our research institute, the more disturbing factors are in the water-poor areas, the dual electric measurement method we independently invented has the strongest ability to distinguish aquifers, and it is more effective than any other method much better.
3. To adopt scientific and reasonable well-forming technology
Under the same geological conditions, in order to maximize the water yield, the minimum drawdown, the best water quality and the longest service life of the well, it is very important whether the well formation process is scientific and reasonable.
1. The filter pipe should face the aquifer. Once the two are misaligned, the water resistance will be much greater, increasing the drawdown. For this reason, geophysical detection wells must be carried out before the pipe is run to accurately determine the location of the aquifer. The patented technology of our research institute - the bipolar double meter electrical logging method is a simple and practical logging method.
2. The opening ratio of the filter pipe should be sufficient. No matter what the pipe opening rate can not be less than 10%. Most of the cement pipes produced by local methods are only 1-2%, and the resistance to water ingress is very high, which is not allowed.
3. There must be pads between the water filter pipe and the filter screen. If there is no reinforcement, the filter screen is tightly attached to the well pipe, and only the mesh facing the water inlet can enter the water, which is very easy to cause blockage, seriously affecting the water output and service life of the well.
4. The size of the filter mesh and gravel filling should be compatible with the aquifer. Otherwise, either the water will be blocked or the muddy water will come out and cause the well.
5. If mud drilling is used, the wall must be broken and the mud changed before the pipe is lowered.
At present, serious problems such as arbitrary configuration of filter pipes, too low opening ratio of water filter pipes, no reinforcement, unqualified filter screen and gravel filling, and incomplete grout replacement are common in well drilling in the society, which urgently need to be improved. Most of the recharge wells of ground source heat pumps are not well recharged, which is an important reason. The professional drilling team of our Groundwater Research Institute has formulated a complete set of drilling construction regulations in response to the above problems, and the drilling effect is very good whether it is direct circulation or reverse circulation.
Fourth, it is necessary to conduct a pumping test and choose a water pump reasonably
Pumping tests can be combined with well cleaning. Before the completion of well flushing, the water output of the pump, the static water level, and the dynamic water level should be measured, and the unit water output of the well, the maximum possible water output and the appropriate pump water volume should be calculated. At present, the vast majority of wells do not have the above data. We only know whether a few kilowatts of water pumps are enough to pump, so we can only choose pumps blindly. The water pump with the highest head is selected according to the depth of the well, which is a serious waste of energy.
According to our experience, as long as the above work is done well, it is easy to increase the success rate of drilling wells and the energy saving rate of pumping water by 20-30% on the current basis. If it can be popularized across the country, the potential is huge. of.
How to drill wells without missing a beat? Packing water can double your price
5. Whether it is drilling artificial wells or deep wells, the price of water-included and non-water-included is different. Water-included drilling needs to bear certain risks, so the price will be much higher than that of non-water-included. As a well-drilling engineer, as long as you can find out the water level and locate it accurately, and you can do everything right, will all the project funds be paid to your account, and will your income increase? Also as the well user of Party A, the well that does not include water fetching also bears the risk of not being able to tap water, and also needs to pay the well digger. Is it not worth it? At this time, accurate positioning of the water source is also very important. necessary.
It is unscientific to judge whether there is water in the ground by experience. It is normal for the same piece of land to have water here and no water at a certain distance. At this time, you can use the water finder to judge the water source and locate the depth of the water source. Thereby solving the problem of finding water.