Well is the smallest water conservancy project since ancient times, but it is also a special water conservancy project involving multiple disciplines. Its characteristics, one is the universality of use. Whether it is large-scale farmland irrigation or scattered small and medium-sized enterprises, most of them rely on wells to provide water, and there are few units and individuals who are not unrelated to the wells. How difficult to detect the quality of the well, once the quality problem can not be remedied; the third is the high risk of investment. There are a large number of drilling and drilling holes. If you do not talk about science and blindly drill wells, most places fail more than succeed. Once there is no water, the investment of several thousand yuan to tens of thousands of yuan will be floated. In this sense, the well is another hydraulic project with the highest risk and the most failures; the fourth is the technical complexity. It is generally considered that drilling a well is "drilling an eye and putting down a root canal". It seems simple, and the actual technical content is very high. It involves many aspects of knowledge such as hydrogeology, geophysical prospecting, well completion technology, and pump selection. Pay attention to it, it is easy to have problems with many failures, poor quality and high risks. Although the knowledge of digging wells and finding water is very deep, it is still of great benefit if the parties concerned acquire scientific knowledge and reduce blindness.
1. We must study the local hydrogeological conditions in detail. If you do not understand hydrogeology and do not study hydrogeological conditions, only trust the instrument and make random measurements everywhere, you can only call it "blind measurement". Research can be conducted from the following three aspects.
1. Study topography. The topography and landform conditions determine the groundwater recharge and discharge conditions, control the weathering of rocks, and affect the abundance and changes of groundwater. Reservoir repairs must have a drainage area, and wells must also have a supply area. The reason is the same. If the lithology conditions are the same, the low-lying terrain or the terrain conducive to catching water is easier to form a well. However, under the small depressions of some small plains, muddy rocks tend to be the main ones, which are easily weathered and eroded to form lowlands, but the groundwater is not good.
2. Study the water richness of the rock. Rocks can be divided into three major categories: igneous rocks, metamorphic rocks, and sedimentary rocks according to their genesis. Subdivision is very complicated. Regardless of the cause, some feel "burden" (rigid), some "sponge" (flexible), some "brittle" (brittle), brittle rock and limestone soluble rock Easy to become well.
3. Study the development of rock fissures. The cracks near the fault fracture zone are more developed. Inclined rocks are more likely to develop cracks than horizontal rocks.
Second, we must choose the method of geophysical prospecting for the local geological conditions
At present, the geophysical prospecting method is mainly electric exploration. Electric exploration methods are divided into artificial electric field method and spontaneous electric field method. There are many specific methods. Commonly used are dual electrical measurement method, high density electrical measurement method, vertical electrical sounding, quadrupole symmetrical profile method, combined profile method, excited polarization method, etc. Each method has its applicable conditions and Interference factors must be selected according to local conditions. After many years of research on water search in our institute, the more interference factors in the poor water area, the better the ability of using our self-invented double electrical detection method to find water to the aquifer, which is more effective than any other method. Much better.
3. A scientific and reasonable well-forming process should be adopted
Under the same geological conditions, it is important to make the well formation technology scientific and reasonable in order to maximize the water output of the well, minimize the drawdown, provide the best water quality and have the longest service life.
1. The water filter pipe should face the aquifer. Once the two are misaligned, the inlet resistance is much greater, increasing the depth. For this reason, a physical detection well must be carried out before the down pipe is run to accurately determine the location of the aquifer. The patented technology of our research institute-bipolar dual meter electric logging method is a simple and practical logging method.
2. The opening rate of the water filter pipe should be sufficient. No matter what the pipe opening rate should not be less than 10%. Most of the cement pipes produced by the local method are only 1-2%, and the resistance to water inflow is very large, which is not allowed.
3. There must be ribs between the water filter pipe and the filter screen. If there is no ribs, the filter mesh is closely attached to the well pipe, and only the mesh facing the water inlet hole can enter the water, which is very easy to cause blockage and seriously affect the water output and service life of the well.
4. The mesh size and size of the gravel should be compatible with the aquifer. Otherwise, it is either water blocking or muddy water caused by the well.
5. For drilling with mud, the wall must be broken and replaced before going down the pipe.
At present, there are serious problems in the society of arbitrarily configuring the water filter tube, the water filter tube opening rate is too low, no reinforcement is added, the filter screen and gravel are unqualified, and the wall replacement and slurry replacement are not thorough. Most recharge wells of ground source heat pumps are not well recharged, which is an important reason. Our professional drilling team of the Groundwater Research Institute has formulated a set of drilling construction regulations for the above problems. Whether it is positive circulation or reverse circulation drilling, the results are very good.
4. Pumping test shall be carried out, and the pump shall be selected reasonably
Pumping tests can be performed in conjunction with well washing. Before the end of the well washing, the actual water output, the static water level, the dynamic water level, the unit water output of the well, the maximum possible water output, and the appropriate pump water volume should be calculated. At present, most wells do not have the above data. I only know that a few kilowatts of pumps are enough to pump. I can only choose the pump blindly. The deeper the well is, the higher the pump height is selected, which is a serious waste of energy.
According to our experience, as long as the above work is done, it is easy to increase the success rate of well drilling and the energy saving rate of pumping by 20-30% on the existing basis. If it can be popularized throughout the country, the potential is huge of.
How to do well without hitting the well? Packing water can double your price
Regardless of whether it is drilling an artificial well or drilling a deep well, the price of water-packed and non-water-packed pumps is different. Water-packed pumps need to bear certain risks, so the price will be much higher than that of water-free pumps. As far as the well drilling engineers are concerned, as long as they can find the correct water level and locate it, so that the project will not be missed, will all the project money be paid to your account, and will the income rise? The same is used for Party A. Wells, wells that do not include water drawers also bear the risk of not producing water, and they also need to pay the well drawer's money. Is it not worthwhile? At this time, accurate positioning of the water source is also necessary.
It is unscientific to judge whether there is water in the ground based on experience. It is normal for there to be water in the same land, and there is no water at a distance. At this time, you can use a water meter to determine the water source and locate the water source depth. So as to solve the problem of finding water difficult.