Oil is produced from the bottom of the well, and generally enters the oil-gas gathering and transportation pipeline after simple oil-water separation at the wellhead. Any oil that does not enter the gathering pipeline during oil production, but is scattered on the ground in the oil production area or leaked from the oil pipeline (such as oil leakage caused by criminals stealing oil from the pipeline that is transporting oil) is usually called "landing oil". Landing oil usually means that the oil in an oil well gushes out of the ground due to excessive pressure in the underground reservoir (this phenomenon is called "blowout"). In the past, before some oil wells began to produce (usually the first well in a newly discovered oil area), oil would be consciously ejected from the wellhead. This production process is called "blowout" and its purpose is to "seek production", that is, to observe and record how much oil this well can produce in a certain period of time (several hours or a day). After blowout, there is always some oil that cannot be recovered (this method is no longer used now), resulting in landing oil. In addition, there are always some equipment in the oil well, such as tubing that makes the oil flow from the bottom oil layer to the wellhead equipment, sucker rod of the oil pump, etc. When these devices come out of the well, there will always be some oil scattered on the ground; If the oil pipeline and wellhead equipment of oil production wells run, run, drip and leak, some oil will leak to the ground. It should also be noted that in order to steal oil, some lawless elements will open valves at the wellhead to control the outflow of oil, or drill holes in the gathering and transportation oil pipeline to form a large amount of landing oil. On June 23, 2002, Yang 1 well in Shengli Oilfield, criminals stole oil and opened the wellhead control valve, resulting in a blowout and the accident site after the blowout. It is estimated that our country produces more than 654.38 million tons of landing oil every year for various reasons, and the direct economic loss reaches tens of millions of yuan.
The site of Yang 1 well in Shengli Oilfield after the blowout caused by criminals stealing oil.
The oil on the ground forms a mixture with the soil on the ground, and the volatile components of the oil will pollute the air when they enter the atmosphere, and will pollute the water body when they enter the water body with rainwater or water flow. After oil seeps into the soil, if plants absorb oil, it will destroy the metabolic process of plants, or block the water and nutrients needed by plants, which will lead to plant death and vegetation destruction. Moreover, the soil polluted by landing oil has lost its agricultural and animal husbandry functions in a few years or even decades.
In order to reduce the landing of oil, a series of technologies and equipment are used in oil exploitation and various underground operations to prevent oil from running, leaking, dripping and leaking. At the same time, there are also systems and measures to clean up and recover oil spills in time, which will minimize oil spills during normal oil production. However, the criminal activities of criminals stealing oil are still repeated, which should arouse the vigilance of the whole society, because not only the oil resources are lost, but also the deterioration of the local ecological environment.