Oil-containing waste clay thermal desorption and calcination integrated device

Abstract

The utility model relates to dangerous waste treatment and resource recycling technical field discloses a kind of oil-containing waste white clay thermal desorption and calcination integrated device, including feeding mechanism, integrated furnace, heating mechanism, oil gas recovery mechanism, gas control mechanism and discharging mechanism;Heating mechanism is used to heat integrated furnace, the exhaust port of integrated furnace and oil gas recovery mechanism intercommunication, and oil gas recovery mechanism is used to carry out oil and water recovery to gas discharged by integrated furnace;Discharging mechanism and integrated discharge port intercommunication, and gas control mechanism includes steam / air pipe, and steam / air pipe is communicated with integrated furnace.Oil-containing waste white clay is first realized oil product recovery by thermal desorption, then directly heated calcination in the same furnace body without cooling to remove residual organic matter in white clay, restore its adsorption performance, the scheme realizes continuous completion thermal desorption oil fraction recovery and residue calcination regeneration in the same furnace body, significantly reduces fuel demand by waste heat utilization, can efficiently complete oil fraction recovery and white clay regeneration.

Description

Technical Field

[0001] This utility model relates to the field of hazardous waste treatment and resource recycling technology, specifically to an integrated device for thermal desorption and calcination of oily waste clay. Background Technology

[0002] Oily waste bleaching clay is a hazardous waste from the petrochemical industry. It is grayish-black and muddy in appearance, with a solvent odor. The main components of oily waste bleaching clay are original activated clay and about 30% oil.

[0003] Traditional methods for disposing of waste bleaching clay include direct landfill and incineration followed by landfill. Both methods cause severe pollution to the ecological environment, especially land and air, and result in significant resource waste. Therefore, current methods primarily focus on extracting oils from waste bleaching clay for resource utilization. These methods mainly include: mechanical high-pressure filtration, centrifugation, supercritical CO2 treatment, aqueous solutions, and surfactants. Mechanical high-pressure filtration uses high pressure to extrude and separate the oils from the waste bleaching clay. Centrifugation uses centrifugal force to separate the clay and oils based on their density difference. Supercritical CO2 treatment utilizes CO2 to extract oils from the pores of the waste bleaching clay, thus separating the clay and oils. Aqueous solutions use water to replace the oils in the pores of the waste bleaching clay. Surfactants reduce the interfacial tension between the clay and oils, allowing the oils to detach from the clay. However, the above methods do not fundamentally solve the problem of harmless treatment of waste bleaching clay, nor do they effectively enable the secondary utilization of the treated waste bleaching clay. Furthermore, these methods can cause secondary pollution to the environment. In addition, the treatment of oily waste bleaching clay requires consideration of both oil recovery and clay regeneration. These processes are often handled by separate equipment, resulting in significant heat loss, high fuel consumption, and cumbersome procedures. Utility Model Content

[0004] The present invention aims to provide an integrated device for thermal desorption and calcination of oily waste clay, so as to solve the problems of cumbersome process and excessive energy consumption caused by the current waste clay recycling device and the separate thermal desorption and calcination.

[0005] To achieve the above objectives, this utility model adopts the following technical solution: an integrated device for thermal desorption and calcination of oily waste bleaching clay, comprising a feeding mechanism, an integrated furnace, a heating mechanism, an oil and gas recovery mechanism, a gas control mechanism, and a discharging mechanism; the feeding mechanism is used to add oily waste bleaching clay into the integrated furnace, the heating mechanism is used to heat the integrated furnace, the exhaust port of the integrated furnace is connected to the oil and gas recovery mechanism, the oil and gas recovery mechanism is used to separate and recover oil, water, and gas from the gas discharged from the integrated furnace; the discharging mechanism is connected to the discharge port of the integrated furnace, and the gas control mechanism includes a steam / air conduit, which is connected to the integrated furnace.

[0006] The principle of this scheme is as follows: The feeding mechanism adds oily waste bleaching clay to the integrated furnace, and then the heating mechanism heats the integrated furnace to the thermal desorption temperature. At the same time, steam or nitrogen is added to the integrated furnace through the steam / air duct to promote the volatilization of oil and gas in the oily waste bleaching clay and inhibit the combustion of the oily waste bleaching clay. The steam or nitrogen carries the volatilized oil and gas into the oil and gas recovery mechanism to separate and recover oil and non-condensable gas. After a preset time, air or oxygen is added to the integrated furnace through the steam / air duct, and at the same time, the heating mechanism heats the integrated furnace to the calcination temperature. The organic matter and impurities in the residue are oxidized and removed, restoring the porosity of the bleaching clay.

[0007] Advantages of this scheme: Thermal desorption and calcination operations are performed sequentially within the same furnace, enabling oil recovery and waste clay regeneration to be completed in a single furnace, simplifying equipment structure, reducing floor space, and improving processing efficiency; Alternating thermal desorption and calcination fully utilizes the waste heat from both process stages for subsequent operations, reducing fuel consumption and lowering fuel requirements and energy consumption compared to traditional step-by-step processes; Steam is introduced during the thermal desorption stage, promoting the volatilization of oil and gas in the oily waste clay while simultaneously inhibiting oil combustion, resulting in a higher oil recovery rate; The recovered oil can be reused, and non-condensable gas and oil can be used as fuel, achieving full-process resource utilization and high recycling rates for waste clay.

[0008] Preferably, the connection point between the steam / air duct and the integrated furnace is located at the feed end of the integrated furnace. This allows the gas inside the integrated furnace to flow from the feed end to its exhaust port, effectively avoiding the problem of flue gas being discharged from the feed end; at the same time, the steam / air is used to cool the equipment at the feed inlet of the integrated furnace to a certain extent, reducing the risk of overheating and deformation damage to the corresponding equipment.

[0009] Preferably, the integrated furnace is tilted, with the feed end higher than the discharge end. This allows the oily waste clay to flow from the feed end to the discharge end under gravity, making discharge from the integrated furnace easier. The downward movement of the oily waste clay causes slight flow and tumbling, allowing steam and air to fully contact the waste clay, promoting oil volatilization and waste clay combustion.

[0010] Preferably, the oil and gas recovery mechanism includes an oil and gas conduit, a condenser, and an oil-water separator connected in sequence. Flue gas from the integrated furnace enters the condenser through the oil and gas conduit for condensation. Non-condensable gases and liquids enter the oil-water separator. The non-condensable gases are discharged from the top of the oil-water separator. The oil and water separate due to their density difference and are then discharged from the corresponding discharge ports of the oil-water separator.

[0011] Preferably, the system also includes a non-condensable gas collection tank, an oil collection tank, and a water collection tank, which are respectively connected to the corresponding discharge ports of the oil-water separator. The non-condensable gas, oil, and water are collected and stored in these tanks for subsequent reuse.

[0012] Preferably, the feeding mechanism includes a feeder and a feed pipe. The feeder is connected to the integrated furnace via the feed pipe and is located above the integrated furnace. The feeder delivers oily waste clay into the feed pipe, which in turn delivers the oily waste clay into the integrated furnace. Positioning the feeder above the integrated furnace reduces the risk of material jamming in the feed pipe and makes it easier to control the feed rate.

[0013] Preferably, the discharge mechanism includes a screw conveyor and a discharge hopper. The feed end of the screw conveyor is connected to the discharge end of the integrated furnace, and the discharge end of the screw conveyor is connected to the discharge hopper. The screw conveyor transports the calcined clay from the discharge end of the integrated furnace to the discharge hopper for storage.

[0014] Preferably, the discharge end of the screw conveyor is located at the top of the discharge hopper.

[0015] Preferably, the combustion mechanism includes a burner located at the bottom of the integrated furnace. Positioning the burner at the bottom of the integrated furnace maintains the temperature at the bottom of the furnace and ensures combustion stability. Attached Figure Description

[0016] Figure 1 This is a structural schematic diagram of an embodiment of the present utility model. Detailed Implementation

[0017] The following detailed description illustrates the specific implementation method:

[0018] The reference numerals in the accompanying drawings include: 1. Feeder; 2. Integrated furnace; 3. Oil and gas duct; 4. Condenser; 5. Oil-water separator; 6. Non-condensable gas collection tank; 7. Oil collection tank; 8. Water collection tank; 9. Discharge hopper; 10. Screw conveyor; 11. Burner; 12. Steam / air duct.

[0019] The basic implementation examples are as follows: Figure 1 As shown:

[0020] An integrated device for thermal desorption and calcination of oily waste clay includes a feeding mechanism, an integrated furnace 2, a heating mechanism, an oil and gas recovery mechanism, a gas control mechanism, and a discharging mechanism.

[0021] The feeding mechanism is used to add oily waste bleaching clay into the integrated furnace 2. The feeding mechanism includes a feeder 1 and a feed pipe. The feeder 1 is connected to the integrated furnace 2 via the feed pipe and is located above the integrated furnace 2. The feeder 1 conveys the oily waste bleaching clay into the feed pipe, which then conveys it into the integrated furnace 2. Positioning the feeder 1 above the integrated furnace 2 reduces the risk of material jamming in the feed pipe and makes it easier to control the feed rate. The feeder 1 consists of a feed hopper with a valve and a screw feeder. The screw feeder is connected to the front end of the furnace body via the feed pipe and can quantitatively deliver the oily waste bleaching clay into the furnace, preventing oil and gas leakage during thermal desorption. The oily waste bleaching clay includes waste bleaching clay containing lubricating oil, paraffin oil, or vegetable oil, with a moisture content of 0%–95%.

[0022] The integrated furnace 2 is tilted, with its feed end higher than its discharge end. This allows the oily waste clay to flow from the feed end to the discharge end under gravity, making discharge from the integrated furnace 2 easier. The downward movement and tumbling of the oily waste clay ensures sufficient contact between steam and air, promoting oil volatilization and combustion. In this embodiment, the integrated furnace 2 is a horizontal, sealed container made of high-temperature resistant alloy material, achieving continuous "thermal desorption-calcination" operation through temperature control. The integrated furnace 2 is rotatably mounted on a frame, with specific configurations referencing existing technology. The furnace body can rotate, and the waste clay is in a churning state inside. The furnace body remains sealed throughout the heating process to minimize heat loss. The integrated furnace 2 also features an inspection chamber door and a discharge chamber door for easy maintenance and residue removal.

[0023] The heating mechanism is used to heat the integrated furnace 2, and the combustion mechanism includes a burner 11, which is located at the bottom of the integrated furnace 2. Positioning the burner 11 at the bottom of the integrated furnace 2 maintains the temperature at the bottom and ensures combustion stability. A temperature sensor is also installed outside the integrated furnace 2 to monitor the internal temperature. The fuel for the burner 11 is non-condensable gas and recovered oil generated from thermal desorption. The temperature sensor monitors the furnace temperature in real time and adjusts the power of the burner 11 through a corresponding control system: During the thermal desorption stage, the furnace temperature is controlled at 300-500℃, and the thermal desorption time is 20-300 minutes; during the calcination stage, the burner 11 is not shut off, and the power is directly increased to raise the furnace temperature to 550-700℃. By utilizing the residual heat after thermal desorption, the fuel consumption for heating is effectively reduced. Thermal desorption and calcination are carried out sequentially in the same furnace, enabling oil recovery and waste clay regeneration to be completed in the same furnace, simplifying equipment structure, reducing floor space, and improving processing efficiency. By alternating between thermal desorption and calcination, the residual heat from both process stages is fully utilized for subsequent operations, reducing fuel consumption. Compared with traditional step-by-step processes, this reduces fuel demand and energy consumption.

[0024] The gas control mechanism includes a steam / air duct 12, which is connected to the integrated furnace 2. When the temperature inside the integrated furnace 2 reaches the thermal desorption temperature, the steam / air duct 12 adds steam or nitrogen to the integrated furnace 2 to promote the volatilization of oil and gas in the oily waste bleaching clay and simultaneously inhibit the combustion of the oily waste bleaching clay. When the temperature inside the integrated furnace 2 reaches the calcination temperature, the steam / air duct 12 adds air / oxygen to the integrated furnace 2, and the organic matter and impurities in the residue are oxidized and removed, restoring the porosity of the bleaching clay. Introducing steam during the thermal desorption stage promotes the volatilization of oil and gas in the oily waste bleaching clay while simultaneously inhibiting the combustion of oil, resulting in a higher oil recovery rate.

[0025] In this embodiment, two branch pipes are connected to the steam / air conduit 12. One branch pipe is used to introduce steam and nitrogen, while the other branch pipe is used to introduce air and oxygen. A solenoid valve is installed at the connection point between the branch pipe and the steam / air conduit 12. The switching between steam and air is controlled by opening and closing the solenoid valve. A flow valve is also installed on the branch pipe to control the gas flow rate. During the thermal desorption stage: steam or nitrogen is introduced into the furnace through the pipeline as a carrier gas to promote oil and gas volatilization while inhibiting material combustion. During the calcination stage: the valve on the steam branch pipe is closed, and air or oxygen is introduced instead to provide oxygen for the combustion of organic matter and to remove the flue gas generated during calcination, mainly CO and CO2.

[0026] The connection point between the steam / air duct 12 and the integrated furnace 2 is located at the feed end of the integrated furnace 2. This allows the gas inside the integrated furnace 2 to flow from the feed end to its exhaust port, effectively avoiding the problem of flue gas being discharged from the feed end; at the same time, the steam / air is used to cool the equipment at the feed inlet of the integrated furnace 2 to a certain extent, reducing the risk of overheating and deformation damage to the corresponding equipment.

[0027] The exhaust port of the integrated furnace 2 is connected to the oil and gas recovery mechanism, which is used to separate and recover oil, water, and gas from the exhaust gas discharged from the integrated furnace 2. The oil and gas recovery mechanism includes an oil and gas conduit 3, a condenser 4, and an oil-water separator 5 connected in sequence. The flue gas in the integrated furnace 2 enters the condenser 4 through the oil and gas conduit 3 for condensation. Non-condensable gases and liquids enter the oil-water separator 5. Non-condensable gases, including CH4 and C3H8, are discharged from the top of the oil-water separator 5. Oil and water separate due to density differences and are then discharged from the corresponding discharge ports of the oil-water separator 5. The recovered oil can be reused, and the non-condensable gases and oil can be used as fuel, realizing full-process resource utilization and achieving high recycling of waste bleaching clay.

[0028] It also includes a non-condensable gas collection tank 6, an oil collection tank 7, and a water collection tank 8, which are connected to the corresponding discharge ports of the oil-water separator 5. The non-condensable gas collection tank 6, oil collection tank 7, and water collection tank 8 collect and store the oil for subsequent reuse.

[0029] The discharge mechanism is connected to the integrated discharge port. The discharge mechanism includes a screw conveyor 10 and a discharge hopper 9. The feed end of the screw conveyor 10 is connected to the discharge end of the integrated furnace 2, and the discharge end of the screw conveyor 10 is connected to the discharge hopper 9. The discharge end of the screw conveyor 10 is located at the top of the discharge hopper 9. The screw conveyor 10 transports the calcined white clay from the discharge end of the integrated furnace 2 to the discharge hopper 9 for storage. In this embodiment, the screw conveyor 10 is a cooling screw conveyor. The calcined recycled white clay is cooled by the cooling screw and then transported to the discharge hopper 9 for collection.

[0030] The specific implementation process is as follows:

[0031] The principle of this scheme is as follows: Feeder 1 transports oily waste bleaching clay into the feed pipe, which then transports the oily waste bleaching clay into the integrated furnace 2. After the oily waste bleaching clay is added to the integrated furnace 2, the burner 11 is turned on to heat the integrated furnace 2 to the thermal desorption temperature. At the same time, steam / air duct 12 adds water vapor or nitrogen into the integrated furnace 2 to promote the volatilization of oil and gas in the oily waste bleaching clay and inhibit the combustion of the oily waste bleaching clay. The water vapor or nitrogen carries the volatilized oil and gas into the oil and gas recovery mechanism. The flue gas in the integrated furnace 2 enters the condenser 4 through the oil and gas duct 3 for condensation. Non-condensable gas and liquid enter the oil-water separator 5. Non-condensable gas is discharged from the top of the oil-water separator 5. Oil and water separate due to density difference and are then discharged from the corresponding discharge port of the oil-water separator 5. The oil and water are collected and stored through the non-condensable gas collection tank 6, oil collection tank 7, and water collection tank 8 for subsequent reuse. After a preset time, air is added to the integrated furnace 2 through the steam / air duct 12, and the power of the burner 11 is increased to heat the integrated furnace 2 to the calcination temperature. Organic matter and impurities in the residue are oxidized and removed, restoring the porosity of the kaolin. The screw conveyor 10 transports the calcined kaolin from the discharge end of the integrated furnace 2 to the discharge hopper 9 for storage. After calcination, the residual heat is used to perform thermal desorption on the subsequently added oily waste kaolin.

[0032] In this embodiment, the treatment of waste bleaching clay containing lubricating oil is taken as an example: the feed rate is controlled at 1t / h, the atmosphere is water vapor, the temperature of the thermal desorption stage is 400℃, and the residence time is 60min; after the thermal desorption is completed, the atmosphere is changed to air, the heating system directly heats up to 650℃, and the calcination residence time is 90min; the non-condensable gas yield obtained by the recovery system is 6%, the oil recovery rate is 28%, the final regenerated bleaching clay residual oil rate is <0.5%, and the bleaching clay decolorization rate is >85%.

[0033] This solution involves direct heating and calcination after thermal desorption without cooling, utilizing waste heat to reduce fuel consumption. Compared to traditional step-by-step processes, this reduces fuel requirements. Oil recovery and clay regeneration are completed within the same furnace, simplifying equipment structure, reducing floor space, improving processing efficiency, and simplifying operation. The integrated furnace design and continuous heating process solve the problem of high energy consumption in traditional processes, making it suitable for large-scale treatment and resource utilization of oily waste clay in the petrochemical industry. The recovered oil can be reused, and non-condensable gas and oil can be used as fuel. The decolorization rate of regenerated clay is restored to over 90% of that of fresh clay, achieving full-process resource utilization.

[0034] The above descriptions are merely embodiments of this utility model, and common knowledge such as specific technical solutions and / or characteristics are not described in detail here. It should be noted that those skilled in the art can make various modifications and improvements without departing from the technical solution of this utility model. In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "joining," and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances. The scope of protection claimed in this application shall be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.

Claims

1. An integrated device for thermal desorption and calcination of oily waste clay, characterized in that, It includes a feeding mechanism, an integrated furnace, a heating mechanism, an oil and gas recovery mechanism, a gas control mechanism, and a discharging mechanism; the feeding mechanism is used to add oily waste clay into the integrated furnace, the heating mechanism is used to heat the integrated furnace, the exhaust port of the integrated furnace is connected to the oil and gas recovery mechanism, the oil and gas recovery mechanism is used to separate and recover oil, water and gas from the gas discharged from the integrated furnace, the discharging mechanism is connected to the integrated furnace's discharge port, and the gas control mechanism includes a steam / air duct, which is connected to the integrated furnace.

2. The integrated device for thermal desorption and calcination of oily waste clay according to claim 1, characterized in that: The connection point between the steam / air duct and the integrated furnace is located at the feed end of the integrated furnace.

3. The integrated device for thermal desorption and calcination of oily waste clay according to claim 1, characterized in that: The integrated furnace is tilted, with the feed end of the integrated furnace being higher than the discharge end of the integrated furnace.

4. The integrated device for thermal desorption and calcination of oily waste clay according to claim 1, characterized in that: The oil and gas recovery mechanism includes an oil and gas conduit, a condenser, and an oil-water separator connected in sequence.

5. The integrated device for thermal desorption and calcination of oily waste clay according to claim 4, characterized in that: It also includes a non-condensable gas collection tank, an oil collection tank, and a water collection tank, which are respectively connected to the discharge ports of the oil-water separator.

6. The integrated device for thermal desorption and calcination of oily waste clay according to claim 1, characterized in that: The feeding mechanism includes a feeder and a feed pipe. The feeder is connected to the integrated furnace through the feed pipe and is located above the integrated furnace.

7. The integrated device for thermal desorption and calcination of oily waste clay according to claim 1, characterized in that: The discharge mechanism includes a screw conveyor and a discharge bin. The feed end of the screw conveyor is connected to the discharge end of the integrated furnace, and the discharge end of the screw conveyor is connected to the discharge bin.

8. The integrated device for thermal desorption and calcination of oily waste clay according to claim 7, characterized in that: The discharge end of the screw conveyor is located at the top of the discharge hopper.

9. The integrated device for thermal desorption and calcination of oily waste clay according to claim 1, characterized in that: The heating mechanism includes a burner located at the bottom of the integrated furnace.

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