Comfortable operation of a country house can not be called in any way, if it is not supplemented with a network of engineering communications that will provide amenities that are so familiar to a person who lives in a big city. You can carry out such work on your own, without resorting to outside help, which will save on builders. One of the main attributes of a comfortable private house or cottage is, of course, sewerage, and one of the options for its construction is a pressure system. It provides for:
- pump station or single pump;
- pipeline;
- tank or well.
The latter are used to accumulate waste fluids if there is no access to the central sewerage system. It is important to remember that a pressure sewer should be equipped only when it is not possible to install a gravity system.
Working principle
Pressure sewage works according to a certain principle, it provides for the flow of waste fluid from several or one residential building through the systempipelines that go to a well or other wastewater collector. With the help of a pump, which is supplemented with a device for grinding large elements that enter the system along with sewage, or a pumping unit, pipelines divert sewage into the central sewer.
Should I use a pressure sewer
Pressure sewerage has many advantages, among them it is worth highlighting the possibility of using a long pipeline, which is permissible to have a smaller diameter. Among other things, the financial costs of installing and maintaining the system can be reduced, as the treatment plant will be replaced by a pump.
Such a sewerage system is organized in the shortest possible time, and for the arrangement there is no need to carry out unnecessary earthworks, which would otherwise be associated with a large amount of equipment. You can be sure that the risk of clogging is minimized because the system uses the shredders that the pumps are equipped with. Pressure sewerage is also distinguished by a long service life, which is explained by the use of durable pipes, as well as specialized installations. This feature is also due to the absence of bulk elements in wastewater.
Pipe selection
One of the important points in the arrangement of the described system is the choice of pipes for the construction of local sewerage. This is due to the fact that the products will take on quite frequent andhigh pressure surges. The pumping device will start working with a water hammer, which appears on the inner surface of the sewer pipeline.
When choosing pipes, it is necessary to ensure that they can withstand pressure up to 1.6 MPa. It is important to pay special attention to the strength of butt joints, as these nodes are the most vulnerable. If you lay the outer pipe in the area of soil freezing, you may encounter ice plugs during operation, this increases the requirements for the minimum strength of the pipes and their elasticity. That is why products must withstand the expansion of ice at the joints.
Not so long ago, pressure sewerage was equipped only with the use of cast-iron pipes, which were able to withstand high loads. This material is characterized by strength, long service life and resistance to aggressive sewage liquids. But modern systems include polyethylene pressure pipes.
The technique of manufacturing cross-linked polyethylene allows you to get excellent qualities of elasticity and strength. With their help, you can form bends at small angles. To connect PVC sewer pipes, a welding machine should be used that heats the surfaces to a melting point. As soon as the docking is successful, the molecules will interpenetrate, which guarantees a high bond strength.
Installation of pressure sewerage
Laying pressure sewers shouldprovide for the construction of an intermediate septic tank, which is built according to the same principles as a treatment septic tank. Its capacity is made of plastic structures, which are called eurocubes. As alternative solutions, reinforced concrete rings, a concrete cube or improvised materials are used, from which a closed hermetic circuit can be formed.
The intermediate settling tank is closed, closed, but it provides for a ventilation device for the supply of oxygen, which is so necessary for the activity of aerobic bacteria. Activated sludge will accumulate at the bottom of the intermediate sedimentation tank. It contains anaerobic bacteria that can live without oxygen. In the process, sludge is formed, which from time to time must be removed using a cesspool machine. Why should the intermediate tank have a hatch, the dimensions of which will meet the needs of these operations.
Recommendations for work
The pressure external sewage system is equipped according to a certain algorithm, at the first stage of which it is necessary to create a project, then pipes and necessary equipment are purchased, and then excavation work is carried out. The pipeline will be laid in the resulting trenches. The next step will be the installation of pipes and installation of the pump. All parts of the system are connected, if possible, domestic sewage can be connected to the central system.
Collecting well device
Pressure sewage wells are an important link in the construction of such systems. They should be located close to the house, and their bottom must be well waterproofed. Otherwise, there is a possibility that sewage will end up in the ground. Surface finishing is carried out with concrete, fired brick or rubble. The thickness of the wall should be approximately 25 cm.
The outer side is insulated with a layer of bitumen, and from the inside, the well must be plastered and the seams must be rubbed. If the pressure sewer system will include concrete rings, then they are laid on a special slab. In order to extend the life of the pump, the well must have two sections, the first of which will collect wastewater, while the pump itself is installed in the second, it will work after the water overflows from the first compartment and reaches a certain level.
Slope during installation of the pipeline
The slope of the pressure sewer should be approximately three centimeters per linear meter, this is true for a pipe with a diameter of 50 mm or less. If the diameter increases to 110 mm, then the slope should be equal to two centimeters. There is also the maximum possible value for external and internal sewage. PVC pipes for sewerage should be laid taking into account that their total slope from beginning to end should be equal to 15 cm. It is important to consider the level of soil freezing for installing an external sewer system.
Features of laying pressure pipes
Howit is known that one significant advantage of pressure sewage is that the pump is able to provide such a pressure that allows you to lay elements of a sufficiently long length, without taking into account the recommended slope. This is also true for those cases when it is rather difficult to take this parameter into account at large distances.
Pressure pipes contain a grinding mechanism. The first of them should have a large diameter. Such a system can be used, for example, for a vegetable processing plant. There are very few requirements for free-flow sewer pipes, which cannot be said about a pressure system. Gravity sewer, which is open type, can even be laid along the gutters in some areas.
When supplying wastewater through pressure pipes, one should take into account the pressure and mass of the liquid that is in the pipe at a certain moment and in any of the sections. Therefore, such pipes should be laid horizontally, only in this way the excess load on them will decrease. It should also be taken into account that, due to the materials used and the wall thickness, pressure pipes are heavier, so they are not recommended to be laid on supports or racks, this can only be done with a small span. The pressure can be high enough that any bending stress is undesirable.
Conclusion
Today, the most successful solution for pressure sewage is polyethylene pipes, which outwardly do not differ from those made of PVC. But they have greatmargin of elasticity and strength, and also have a large wall thickness. For external noise, such pipes are almost impenetrable, in which they are not inferior to cast iron products.
