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Ground water refers to the water that occurs in the rock voids below the ground, and in a narrow sense refers to the water in the saturated aquifer below the ground water surface. In the national standard "Hydrogeology Terminology" (GB/T 14157-93), groundwater refers to various forms of gravity water buried below the surface. Foreign scholars believe that there are three definitions of groundwater: one refers to all the water buried in groundwater that is significantly different from surface water, especially the part of the water in the saturated zone in the aquifer; the other refers to downward flow or penetration to make soil and rocks It is saturated and replenishes the water of springs and wells; the third is the water stored in the rock cavities underground and in the voids that make up the crustal material. Groundwater is an important part of water resources. Because of its stable water volume and good water quality, it is one of the important water sources for agricultural irri
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Domestic sewage is the waste water discharged in the daily life of residents. It mainly comes from residential buildings and public buildings, such as houses, offices, schools, hospitals, shops, public places and industrial enterprises toilets. The pollutants contained in domestic sewage are mainly organic matter (such as protein, carbohydrate, fat, urea, ammonia nitrogen, etc.) and a large number of pathogenic microorganisms (such as parasite eggs and intestinal infectious virus, etc.). The organic matter in domestic sewage is extremely unstable and easily decomposes to produce foul smell. Bacteria and pathogens multiply by taking organic matter in domestic sewage as nutrients, which can lead to the spread of infectious diseases. Therefore, domestic sewage must be treated before it is discharged. In the process of sewage treatment, firstly it is necessary to detect and analyze the quality of sewage, mainly by detecting the data of SS, COD, BOD, etc. in the water.
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Industrial waste gas detection refers to the general term for the detection of various pollutant-containing gases discharged into the air during the fuel combustion and production processes in the factory area. Industrial waste gas detection includes organic waste gas detection and inorganic waste gas detection. Organic waste gas mainly includes various hydrocarbons, alcohols, aldehydes, acids, ketones and amines; inorganic waste gas mainly includes sulfur oxides, nitrogen oxides, carbon oxides, halogens and their compounds. Industrial waste gas has different treatment methods according to its exhaust air volume, temperature, concentration and its own chemical and physical properties. Industrial waste gas is an important source of air pollutants. A large amount of industrial waste gas is discharged into the atmosphere, which will inevitably reduce the quality of the atmospheric environment, bring serious harm to human health, and cause huge losses to the national economy. After harmful
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All sounds that hinder people's normal rest, study and work, as well as sounds that interfere with the sounds people want to hear, are all noise. In this sense, there are many sources of noise, such as the sound of cars on the street, the sound of talking in a quiet library, the sound of machinery on construction sites, and the excessively loud sound of neighboring TV sets. Noise is a kind of physical pollution. It refers to the unwanted and annoying sound of people. It is considered to be the third largest public hazard after air pollution and water pollution, and causes great harm to human health. Test items: 1. Environmental noise (regional environmental noise, road traffic noise) 2. Industrial enterprise plant boundary noise 3. Social life environmental noise 4. Construction site boundary noise 5. Workplace noise, vibration
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Working principle The liquid resistance detection method is to fill the oil and gas recovery pipeline with nitrogen at the specified nitrogen flow rate, and simulate the oil and gas passing through the oil and gas recovery pipeline. Use a pressure gauge or equivalent device to detect the liquid resistance of the gas passing through the pipeline to understand the degree of resistance to the gas caused by various reasons in the pipe to determine whether it affects the oil and gas recovery. The airtightness detection method uses nitrogen to pressurize the vapor recovery system to 500 Pa, allowing the system pressure to decay. The residual pressure value after 5 minutes of detection is compared with the minimum residual pressure limit specified in Table 2. If it is lower than the limit, it indicates that the leakage degree of the system exceeds the allowable range. The gas-liquid ratio detection method is to install a tight adapter at the nozzle of the fueling gun. The adapter is connected
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Bottom mud is usually a mixture of clay, silt, organic matter, and various minerals. It is formed by depositing at the bottom of the water body after a long time of physical, chemical, and biological action and water transmission. The sediment with a thickness of 0 to 15 cm on the surface is called surface sediment, and the sediment with a thickness of more than 15 cm is called deep sediment. Bottom mud is the sediment of rivers and lakes and an important part of natural waters. When the water area is polluted, part of the pollutants in the water can be stored in the bottom sludge through precipitation or particulate matter adsorption, and then released under appropriate conditions to become a source of secondary pollution. This type of pollution is called bottom sludge pollution. Test items: mercury, lead, cadmium, copper, zinc, chromium, nickel, arsenic and other heavy metals or inorganic non-metallic toxic substances, total nitrogen, total phosphorus, PH, moisture content, organic m
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