A power failure protection system for oil field thermal desorption device

Abstract

The present invention belongs to the technical field of thermal desorption treatment of oil-containing sludge and oil-based cuttings of oilfield drilling waste, and in particular, it relates to a power-off protection system for a thermal desorption device in an oilfield, which is characterized by comprising a diesel generator drive system, a device supporting protection system connected to the diesel generator drive system, and the device supporting protection system comprises a nitrogen making device, a hot blast furnace, an induced draft fan and a blower connected to the diesel generator drive system, and an air filter connected to the blower. The present invention has a high degree of automation and flexible control. The protection value feedback thermal desorption device power-off protection system can be set according to the furnace pressure, combustible gas concentration and oxygen content in the thermal desorption gas after the thermal desorption furnace is powered off. The diesel generator drive system and the equipment contained in the device protection system are started in sequence through a control program, thereby reducing the concentration of the thermal desorption gas in the thermal desorption furnace and avoiding the safety hazards such as explosion caused by the mixing of a large amount of thermal desorption gas with the outside air.

Description

Technical Field

[0001] The invention belongs to the technical field of thermal desorption treatment of oil-containing sludge and oil-based cuttings from oilfield drilling waste, and in particular relates to a power-off protection system for an oilfield thermal desorption device. Background Art

[0002] The current thermal desorption treatment technology for oily sludge and oil-based drill cuttings from oilfield drilling waste is mature and diverse. The main design parameters of the device, such as the processing capacity and oil content after treatment, can fully meet the standards or even be higher. However, when the thermal desorption treatment technology is met, the device contains a complex system and many equipment, and some device operation safety issues are often ignored to varying degrees. At present, there are few emergency treatment technical methods in the existing technology for sudden power outages and shutdowns during the normal operation of the thermal desorption device due to some reasons in the well site or station area, and the safety hazards cannot be ignored. Because the oil content of oily sludge or oil-based drill cuttings is high, in order to achieve the oil content index after treatment, the higher the temperature is, the more obvious the effect is, and the greater the amount of thermal desorption gas (high temperature, flammable, harmful) is generated. Due to power outage, all systems and equipment of the device are in an immediate shutdown state, but the high temperature of the thermal desorption furnace will not immediately drop below the pyrolysis temperature due to the shutdown of the device systems and equipment. The untreated or newly entered oily sludge or oil-based drill cuttings will continue to produce a large amount of thermal desorption gas due to high-temperature cracking in the thermal desorption furnace. At this time, the pressure of the thermal desorption furnace will increase, the gas will escape everywhere, and the concentration of flammable and harmful gases will increase. This requires emergency technical measures such as the device power-off protection system to protect the safety of the device, on-site personnel and the surrounding environment. Summary of the invention

[0003] The purpose of the present invention is to provide a power failure protection system for an oil field thermal desorption device, which solves the problem that when a well site or station area suddenly loses power due to some reason and oil-containing sludge or oil-based drill cuttings in the thermal desorption furnace cannot be discharged in time, and thermal desorption gas is continuously cracked at high temperature and continuously generated, it may cause hidden dangers to the safe operation of the device, the personal safety of personnel and the surrounding environment.

[0004] The objective of the present invention is achieved through the following technical solutions:

[0005] The oilfield thermal desorption device power failure protection system of the present invention is characterized in that it includes a diesel generator drive system, a device supporting protection system connected to the diesel generator drive system, the device supporting protection system includes a nitrogen making device, a hot air furnace, an induced draft fan and a blower connected to the diesel generator drive system, an air filter connected to the blower, the blower is connected to an air condenser, the induced draft fan is connected to the air condenser through a combustible gas pipeline, and the hot air furnace is connected to the hot air furnace through a hot air pipeline.

[0006] The diesel generator drive system comprises a diesel generator, a power distribution cabinet and a control cabinet.

[0007] Advantages of the present invention:

[0008] The oilfield thermal desorption device power-off protection system of the present invention has a high degree of automation and flexible control. It can set protection values ​​to feedback the thermal desorption device power-off protection system according to the furnace pressure, combustible gas concentration and oxygen content in the thermal desorption gas after the thermal desorption furnace is powered off. The diesel generator drive system and the equipment contained in the device protection system are started in sequence through a control program, thereby reducing the concentration of the thermal desorption gas in the thermal desorption furnace, avoiding safety hazards such as explosion caused by mixing a large amount of thermal desorption gas with the outside air, ensuring the safe and reliable shutdown of the thermal desorption device, and reducing the escape of harmful gases around the well site or station area, thereby protecting the personal safety of on-site personnel and reducing pollution of the on-site and surrounding environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 It is a process flow chart of the present invention. DETAILED DESCRIPTION

[0010] The specific implementation of the present invention is further described below in conjunction with the accompanying drawings.

[0011] like Figure 1 As shown, the power-off protection system for the oilfield thermal desorption device of the present invention is characterized in that it includes a diesel generator drive system 1, and a device supporting protection system connected to the diesel generator drive system 1, wherein the device supporting protection system includes a nitrogen making device 6, a hot blast furnace 2, an induced draft fan 3 and a blower 5 connected to the diesel generator drive system 1, an air filter 4 connected to the blower 5, the blower 5 is connected to an air condenser 10, the induced draft fan 3 is connected to the air condenser 10 via a combustible gas pipeline, and the hot blast furnace 2 is connected to a hot blast furnace chamber via a hot blast pipeline.

[0012] The diesel generator drive system 1 comprises a diesel generator, a power distribution cabinet and a control cabinet.

[0013] The oilfield thermal desorption device power failure protection system of the present invention comprises a diesel generator drive system 1 and a device supporting protection system. The diesel generator drive system 1 is composed of a diesel generator, a power distribution cabinet and a control cabinet. The device supporting protection system is composed of a nitrogen generator 6, an induced draft fan 3, an air filter 4, a blower 5, and a hot air furnace 2.

[0014] The thermal desorption treatment system consists of a thermal desorption furnace 7, a gas-solid separator 8, a dry filter 9, an air condenser 10, an induced draft fan 3, an exhaust gas treatment device, an inlet and outlet device, an oil and gas condensation collection device and a water cooling device.

[0015] When the well site or station area suddenly loses power for some reason, the thermal desorption treatment system stops working. The thermal desorption furnace cannot push the material due to the power failure, and the oily sludge or oil-based drill cuttings in the furnace cannot be discharged in time. However, the furnace is still in a high temperature state at this time. The thermal desorption gas (high temperature, flammable, harmful gas) continuously generated by the oily sludge or oil-based drill cuttings in the high temperature state increases the furnace pressure and escapes everywhere, and the concentration of flammable and harmful gases gradually increases. Figure 1 As shown, when the thermal desorption treatment system suddenly loses power due to some reason during normal operation, a large amount of thermal desorption gas generated by the failure to remove the material in the thermal desorption furnace in time causes the furnace pressure and the concentration of combustible gas to increase to the set protection value or above, the diesel generator drive system 1 is first started through the interlocking automatic control program to provide power. Then, the blower 5 of the device supporting protection system is started in sequence through the automatic control program to provide cooling medium for the air condenser, and the blower motor 5 is started to filter the air through the air filter 4 and then enter the shell side of the air condenser 10 through the volute of the blower 5 to provide cooling medium; the burner of the hot blast furnace 2 of the device supporting protection system is started to make the hot air blow through the air inlet pipeline to sweep the hot blast furnace chamber, and after several minutes, the induced draft fan 3 of the device supporting protection system is started to reduce the furnace pressure of the thermal desorption furnace to a negative pressure state, and the thermal desorption gas generated by the high temperature of the oil sludge or oil-based drilling cuttings in the thermal desorption furnace 7 is filtered out of solid dust impurities through the gas-solid separator 8 and the dry filter 9, and the remaining non-condensable gas (combustible gas such as methane) is extracted through indirect cooling and condensation of the air in the tube side and shell side of the air condenser 10, and enters the hot blast furnace 2 burner gas pipeline of the device supporting protection system, and is ignited and burned fully and temporarily discharged through the burner. When the oxygen content in the thermal desorption gas reaches the set protection value, the nitrogen making device 6 of the device supporting protection system is started to prepare 99% pure nitrogen and continuously enter the thermal desorption furnace through the pipeline to replace the oxygen entering the thermal desorption furnace until the furnace temperature drops below the pyrolysis temperature of the oily sludge or oil-based drill cuttings and no thermal desorption gas is produced. Then the nitrogen making device 6, the induced draft fan 3, the hot blast furnace 2, the blower 5 and the diesel generator drive system 1 of the device supporting protection system are shut down in sequence to solve the safety hazard caused by power failure at the thermal desorption device site.

[0016] The oilfield thermal desorption device power-off protection system of the present invention has a high degree of automation and flexible control. It can set a protection value feedback to the thermal desorption device power-off protection system according to the furnace pressure, combustible gas concentration and oxygen content in the thermal desorption gas after the thermal desorption furnace is powered off. The diesel generator drive system 1 and the equipment contained in the device protection system are started in sequence through a control program, thereby reducing the concentration of the thermal desorption gas in the thermal desorption furnace, avoiding the safety hazards such as explosion caused by the mixing of a large amount of thermal desorption gas with the outside air, ensuring the safe and reliable shutdown of the thermal desorption device, and reducing the escape of harmful gases around the well site or station area, thereby protecting the personal safety of on-site personnel and reducing pollution of the on-site and surrounding environment.

Claims

1. A power-off protection system for an oilfield thermal desorption device, characterized in that It includes a diesel generator drive system, a device supporting protection system connected to the diesel generator drive system, the device supporting protection system includes a nitrogen making device, a hot blast furnace, an induced draft fan and a blower connected to the diesel generator drive system, an air filter connected to the blower, the blower is connected to an air condenser, the induced draft fan is connected to the air condenser through a combustible gas pipeline, the hot blast furnace is connected to a hot blast furnace through a hot blast pipeline, The diesel generator drive system is started to provide power, and the blower motor of the supporting protection system of the starter device is used to filter the air through the air filter and then enter the shell side of the air condenser through the blower volute to provide cooling medium; the burner of the hot air furnace of the supporting protection system of the starter device allows the hot air to blow the hot air furnace through the air inlet pipeline. After several minutes, the induced draft fan of the supporting protection system of the starter device is started to reduce the furnace pressure of the thermal desorption furnace to a negative pressure state, and the thermal desorption gas generated by the high temperature of the oil-containing sludge or oil-based drilling cuttings in the thermal desorption furnace is filtered out of solid dust impurities through the gas-solid separator and dry filter, and then is discharged between the tube side and the shell side of the air condenser. The remaining non-condensable gas after cooling and condensation is extracted and enters the gas pipeline of the hot blast furnace burner of the device supporting protection system, is ignited and burned fully and temporarily discharged through the burner. When the oxygen content in the thermal desorption gas reaches the set protection value, the nitrogen making device of the device supporting protection system is started to prepare 99% pure nitrogen, which continuously enters the thermal desorption furnace through the pipeline to replace the oxygen that leaks into the thermal desorption furnace, until the furnace temperature drops below the pyrolysis temperature of oily sludge or oil-based drill cuttings and no thermal desorption gas is generated, and then the nitrogen making device, induced draft fan, hot blast furnace, blower and diesel generator drive system of the device supporting protection system are shut down in sequence.

2. The oilfield thermal desorption device power failure protection system according to claim 1 is characterized in that The diesel generator drive system comprises a diesel generator, a power distribution cabinet and a control cabinet.

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