With the development of related technologies such as mechanical cleaning technology for oil tanks and the state's emphasis on the research of oil tank cleaning technology, enterprises continue to innovate and develop, China's oil tank cleaning technology and technology develop rapidly, and the level of automation is constantly improving. In addition, China has made great breakthroughs in actively learning and learning from the international mature oil tank automatic cleaning technology and realizing the localization of the whole set of equipment, resulting in good social and economic benefits.
1. Prospects for mechanical cleaning of oil tanks.
From the perspective of macro-industry development trend, since November 2006, the State Administration of Work Safety convened a "Symposium on Safety Management Standards for PetroChina Storage and Transportation". The meeting discussed how to further strengthen the safety management of PetroChina storage and transportation and the application prospect of mechanical cleaning technology for oil storage tanks, and affirmed the mechanical cleaning technology. Compared with manual cleaning, it has the advantages of energy saving, safety, environmental protection, economy and so on. Next, the State Administration of Work Safety will improve the safety management standards for petroleum storage and transportation, promote the wide application of mechanical cleaning technology in petroleum storage and operation industry, and promote the standardization and standardization of tank cleaning operations.
At present, the Technical Standards for Mechanical Cleaning of Storage Tanks, led by China National Petroleum Corporation and participated by Daqing Oilfield Company Limited and Maoming Petrochemical Company, have been examined and approved by the Technical Committee for Standardization of Oil and Gas Storage and Transportation Speciality in the Petroleum Industry, and will be issued and implemented by the National Development and Reform Commission in 2007. One of the people's Republic
Industry standard. The promulgation and implementation of the industry standard will play a strong role in regulating the cleaning operation of storage tanks.
With the development and progress of society and the importance of health, safety and environmental protection, the advantages of oil tank mechanical cleaning technology in safety, environmental protection and efficiency will be accepted and recognized by more users, and its market application prospect is in the ascendant.
2. Cleaning and cleaning process and principle of oil tank
The mechanical cleaning technology of oil tank is to transfer the fluidity oil from the bottom of the cleaning tank to the receiving tank. After heating and pressurizing, the oil from the cleaning oil supply tank is agitated and dissolved by the cleaning machine. After removing the impurities through the filter, the remaining solidified oil is transferred to the receiving tank. Finally, warm water is used to feed the oil into the various parts of the tank. Circulate cleaning to achieve the ignition conditions in the tank. During the cleaning process, the inert gas is continuously injected into the tank to be cleaned, so that the oxygen concentration in the tank can be kept below 8VoL% to prevent explosion and other dangers; equipped with oxygen and combustible gas detection device, the concentration of oxygen and combustible gas in the tank being cleaned is monitored at all times to ensure the safe operation of mechanical cleaning operation.
3, technical advantages of oil tank cleaning machinery:
For many years, the oil and petrochemical industry has adopted the method of manual cleaning of oil tanks. Operators wash the oil tanks manually by ladders from the side wall overhaul holes. The space of the tanks is narrow, the air is not circulating, the concentration of combustible gases is high, poisoning and explosion accidents are easy to occur, the working environment is bad, and the workers are seriously damaged. The physical and mental health of the staff;
On the other hand, the filthy oil removed from the tank and the large amount of sewage produced by manual scrubbing cause environmental pollution in the tank area and the surrounding areas. At the same time, the long cleaning period (averaging two months) reduces the storage and regulation capacity of the reservoir area, which directly affects the normal production of the reservoir area. A large number of discarded bottom oils also cause waste of resources and environmental pollution. Dyed.
Compared with the traditional tank cleaning method, mechanical cleaning technology realizes the whole process of tank closed cleaning, which has the characteristics of short cleaning time, health, safety, high oil recovery rate, social and economic benefits.
(1) The whole process of closed cleaning, cleaning process personnel do not need to enter the tank, only in the external operation of cleaning equipment, control the cleaning process, construction workers do not directly contact the tank oil, gas, reduce labor intensity, improve the construction conditions.
(2) In the process of cleaning, human inert gas is injected to replace air and combustible gas, reduce the concentration of combustible gas and oxygen, and ensure the safety and reliability of mechanical cleaning operation.
(3) tank cleaning under closed conditions does not pollute the environment around the tank, and meets the requirements of environmental protection. Through oil-water circulation cleaning and oil-water separation process, the bottom oil is filtered out and then re-entered the storage and transportation system in the reservoir area. The recovery rate of the bottom oil is over 98, which improves the oil commodity rate and reduces the resource consumption.
(4) the cleaning cycle is shorter (average half a month), which can effectively improve the storehouse's storage and adjustment ability.
4. Application of oil tank cleaning in Daqing oilfield of China
With the continuous improvement of oil field production management level, higher requirements for safety, health, environmental protection and quality are put forward. Manual cleaning of storage tanks has been unable to meet the needs of modern petroleum enterprises. In view of this, China's Daqing Oilfield in 1998 to investigate and demonstrate the mechanical cleaning technology, and imported from foreign oil tank mechanical cleaning professional equipment.
In 1999, after the domestic matching transformation, the trial run, after more than two years of practice, summed up the formation of a mature mechanical cleaning process. The bottom oil of mechanical tank cleaning is calculated according to the average depth of oil storage after the bottom of the floating vessel of the tank is 0.3 M. Taking the 5X104m3 oil tank as an example, the recoverable oil amount reaches 750 t, which is all commercial crude oil. Mechanical cleaning of a 5X104m3 oil tank can bring more benefits than manual cleaning of 2.55 million yuan. In 2003, China's Daqing oilfield fully implemented the mechanical cleaning technology of oil storage tanks.
Up to 2006, the average annual cleaning of more than 30 large and small oil tanks, recovered more than 10,000 tons of commodity crude oil, reduced the annual consumption of commodity crude oil nearly 40 million yuan.
5. Oil tank cleaning is an inevitable trend.
With the large scale of crude oil storage tanks, the traditional manual cleaning operation can no longer meet the production requirements. The main reason is that manual cleaning is difficult, long cycle and so on, manual operation into the tank, may cause personnel poisoning and fire and explosion accidents. Therefore, mechanized cleaning technology of tank will replace manual cleaning. Mechanical operation instead of manual operation is an inevitable trend in the development of human society, which is irresistible.
About cleaning process:
1, oil transfer: through the transfer module, the liquid oil in the cleaned tank can be transferred to the receiving tank.
2. Equipment Installation: Use light pipeline and valve to quickly complete the installation of equipment and pipeline connection, and test the overall tightness of the system;
3. Same kind of oil cleaning: After heating and pressurizing the oil in the oil supply tank by the cleaning module, the solidified oil in the tank to be cleaned is crushed and dissolved by the cleaning machine which is set on the single plate of the tank to be cleaned or the repair hole on the side wall of the tank to make it have better fluidity, and is filtered by the transfer module and transferred to the receiving unit. Oil tank;
4. Warm water cleaning: the clean water added to the oil-water separating module is heated and pressurized by the cleaning module, then the parts of the tank are cleaned by the cleaning machine, and the oil-water mixture in the process of warm water cleaning cycle is separated by the oil-water separating module, and the separated oil is transferred from the recovery pump to the receiving tank and separated. Qingshui continues to warm water washing cycle operation.