Dry quenching waste heat recovery system for semi-coke furnace

Abstract

The utility model relates to a dry quenching waste heat recovery system for a semi-coke furnace, which comprises the semi-coke furnace, and a semi-coke baffle and a coke pushing arm are designed at the bottom of the semi-coke furnace; two conveying belts are designed at the bottom of the semicoke baffle; a coke storage hopper is arranged between the two conveying belts; a temperature-resistant rotary valve is arranged at the bottom of the coke storage hopper; the coke storage hopper is connected with the spiral semi-coke cooler; outlet water of the spiral semi-coke cooler is connected into a flash tank; steam generated by the flash tank is introduced into the steam pocket; and low-pressure saturated steam generated by the steam pocket enters the mixed gas distribution chamber. Compared with other waste heat recovery devices, the device has the advantages that direct contact between cooling water and semi-coke is avoided, so that environment pollution caused by a large amount of pollution steam is avoided, and waste of water resources and energy is avoided. And meanwhile, the system also generates low-pressure saturated steam, and the generated saturated steam is used for preparing mixed gas, so that the quality of semi-coke products, especially tar, is improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to the production of waste heat recovery technology of semi coke, relates to the waste heat recovery system of dry quenching semi coke. BACKGROUND

[0002] China's low rank coal resources are rich, with high volatile matter content, high reactivity, according to its coal quality structure scientific transformation, has important strategic significance for realizing the clean and efficient utilization of coal resources in China. The low rank coal pyrolysis technology can obtain oil and gas products with high added value and high carbon content semi coke (semi coke, the meaning of semi coke is the same as that of semi coke in this document) products. The traditional low rank coal pyrolysis technology adopts water quenching method, not only the sensible heat carried by hot coke cannot be recovered, but also can cause serious waste of energy. In order to solve this problem, the utility model provides a kind of semi coke waste heat recovery system, through the design of cooling chamber and flash tank, realize the dry recovery of hot coke sensible heat. And the recovered hot water is used to produce steam, and circulate back to the mixed gas chamber. CONTENT OF UTILITY MODEL

[0003] The utility model aims at providing a kind of semi coke waste heat recovery and the system of generating steam, and utilize the steam generated as the steam source of mixed gas chamber, to improve product tar quality.

[0004] The technical solution of this utility model is as follows: A waste heat recovery system for dry quenching of semi-coke ovens includes a semi-coke oven, a burner, a mixing and gas distribution chamber, and a cooling chamber. Semi-coke is transferred from the semi-coke oven to the cooling chamber, which is equipped with a flash tank and a steam drum. The cooling chamber is a water-cooled structure, with a water-cooling pipe outlet connected to the flash tank. The flash tank is connected to the steam drum via a pipe. The steam drum is equipped with a steam-water separation element and has a steam outlet pipe and a condensate outlet pipe. The steam outlet pipe is connected to the mixing and gas distribution chamber, and the condensate outlet pipe is connected to the cooling water inlet pipe via an air cooler. The cooling chamber is designed with a conveyor belt, a coke pusher arm, a coke storage hopper, a spiral semi-coke cooler, and a semi-coke baffle. The bottom of the semi-coke oven has a semi-coke baffle and a coke pusher arm. The coke pusher arm controls the opening of the semi-coke baffle and controls the coke discharge rate. The conveyor belt is located below the semi-coke baffle, and the coke storage hopper is located below the material drop end of the conveyor belt to receive the falling semi-coke. The bottom of the coke storage hopper is connected to a semi-coke conveying pipe. The material flows by gravity, and the bottom end of the semi-coke conveying pipe enters the end of the spiral semi-coke cooler drum. The spiral semi-coke cooler has an inner cylinder and an outer cylinder. The outer cylinder has end sleeves at both ends, and the bottom of the end sleeves is supported by a support frame. The outer cylinder body is between the two end sleeves. The outer cylinder body and the end sleeves are connected by a rotary sealing structure. The two ends of the inner cylinder are connected to the end sleeves by fixed rods. The inner cylinder does not rotate, while the outer cylinder body rotates under the drive of an external transmission structure. Multiple paddles are fixed on the inner wall of the outer cylinder body. The paddles push the semi-coke towards the outlet. The outlet of the semi-coke is at the bottom of the tail end sleeve. The head end sleeve has a feed inlet. The bottom end of the semi-coke conveying pipe extends into the spiral semi-coke cooler from the feed inlet. A cooling water circulation pipe is provided between the inner cylinder and the outer cylinder. The cooling water circulation pipe is located around the inner cylinder. The inner cylinder has spiral blades and longitudinal blades. The cooling water inlet and outlet of the cooling water circulation pipe are located at the tail end sleeve. The water inlet direction is opposite to the direction of the semi-coke spiral push.

[0005] Furthermore, the conveyor belt is designed to be horizontal or inclined, with two conveyor belts and a coke storage hopper located between the two conveyor belts, which operate in opposite directions.

[0006] The mechanism that provides rotational force to the outer cylinder includes a support ring, a support wheel, a transmission wheel, and a drive motor. The drive motor is placed on one side of the outer cylinder, and the output shaft of the drive motor is connected to the transmission wheel. The transmission wheel and the support wheel are driven by friction. The support ring is a rotatable support connection to the outer cylinder body.

[0007] The air-water separator element is a wire mesh with multiple layers.

[0008] A rotary valve connects the coke storage hopper and the semi-coke conveying pipe.

[0009] The oxygen in the mixing chamber comes from the VPSA oxygen generator.

[0010] The utility model discloses a beneficial effect: absorb the heat of the semi coke, the saturation steam that the high temperature hot water of recycling utilizes the flash tank to carry out the cooling, as the steam source of mixed gas distribution chamber, saves the energy consumption, improves the quality of semi coke oven tar product of semi coke furnace again. BRIEF DESCRIPTION OF DRAWINGS

[0011] Figure 1 For the waste heat recovery system schematic diagram provided by the embodiment of the application.

[0012] Figure 2 For the spiral semi coke cooler partial structure schematic view provided by the embodiment of the application.

[0013] Wherein: 1 - push the coke arm;2 - conveyer belt;3 - rotary valve;4 - coke hopper;5 - semi coke oven;6 - semi coke baffle;7 - support ring;8 - drive motor;9 - spiral blade;10 - longitudinal blade;11 - cooling water outlet;12 - cooling water inlet;13 - spiral semi coke cooler;14 - semi coke conveying pipe;15 - support wheel;16 - transmission wheel. DETAILED DESCRIPTION

[0014] As Figure 1 Shown, for the waste heat recovery system of a furnace dry quenching of the application, the system core mainly includes: semi coke oven, combustor, cooling chamber, flash tank, steam drum and mixed gas distribution chamber composition.Semi coke is transferred from semi coke oven into cooling chamber, and the cooling chamber is a water cooling structure, and the water cooling pipeline outlet is communicated with the flash tank, and the flash tank is connected with the steam drum through a pipeline, and the steam drum is provided with a steam-water separation element, and the steam drum is provided with a water vapor outlet pipe and a condensed water outlet pipe, and the water vapor outlet pipe is communicated to the mixed gas distribution chamber, and the condensed water outlet pipe is communicated to the cooling water inlet pipe through an air cooler.The cooling chamber is designed with a coke hopper 4, a conveyer belt 2 and a spiral semi coke cooler 13.The system realizes the dry quenching of semi coke oven, thereby avoiding a series of problems caused by water quenching.Further, the saturation steam generated by the high temperature hot water of recycling utilizing the flash tank to carry out the cooling is used as the steam source of mixed gas distribution chamber, that is, the energy consumption is saved, and the quality of semi coke oven tar product of semi coke furnace is improved.

[0015] The semi-coke baffle 6 is controlled by the coke pushing arm 1, and the coke pushing arm 1 pushes the semi-coke baffle 6 to control the size of the opening and the rate of coke discharge. The bottom of the semi-coke baffle 6 is designed with a conveyor belt 2, and the bottom of the conveyor belt 2 is designed with a coke storage hopper 4. The conveyor belt 2 sends the semi-coke into the coke storage hopper 4 for accumulation. The high-temperature semi-coke in the coke storage hopper 4 passes through the rotary valve 3 (high-temperature resistant valve, effectively controlling the amount of coke entering the spiral semi-coke cooler), the semi-coke conveying pipe 14 enters the inside of the spiral semi-coke cooler, and is piled up to a certain height around the inlet pipe. When the gravity generated by the semi-coke and the gravity of the semi-coke in the semi-coke conveying pipe 14 are balanced, the flow of the semi-coke in the semi-coke conveying pipe 14 is blocked. When the semi-coke is pushed by the rotation of the outer cylinder to move towards the semi-coke cooler outlet, the height of the semi-coke pile around the semi-coke conveying pipe 14 decreases, thereby breaking the gravity balance between the semi-coke inside and outside the semi-coke conveying pipe 14, and the semi-coke in the semi-coke conveying pipe 14 flows forward and enters the inside of the spiral semi-coke cooler. In turn, the outer cylinder main body rotates, the high-temperature semi-coke flows in, the outer cylinder main body stops, the high-temperature semi-coke flow stops, the outer cylinder main body rotates fast, the high-temperature semi-coke flows in fast, the outer cylinder main body rotates slowly, and the high-temperature semi-coke flows in slowly. During the process of pushing the semi-coke, the high-temperature semi-coke exchanges heat with the cooling water. Most of the heat of the semi-coke is taken away by the circulating cooling water. The 10 bar cooling water cools the high-temperature semi-coke at 700-800℃ in the cooling chamber to about 200℃. The temperature of the semi-coke decreases, and the semi-coke is transported away by the transportation equipment or stored in the warehouse. The heated cooling water enters the flash tank for pressure reduction and flashing, the steam generated enters the steam drum, and after the steam-water separation of the steam drum, high-quality steam is finally generated, enters the mixed gas chamber, mixes with the gas, and then enters the coke oven for chemical reaction again, thereby improving the quality and yield of the tar.

[0016] The cooling chamber is designed with a conveyor belt 2, a coke storage hopper 4, and a spiral semi-coke cooler 13. The conveyor belt can be designed as a horizontal type or an inclined type to adapt to the working requirements of different semi-coke ovens. The coke storage hopper 4 is designed between the two conveyor belts, and the two conveyor belts run towards each other to transport the high-temperature semi-coke to the coke storage hopper. According to the number of semi-coke ovens, the two conveyor belts can be combined into one conveyor belt, and the coke storage hopper is designed at one end of the conveyor belt. The size and capacity of the semi-coke oven are adjusted to achieve the best coke discharge effect. The conveyor belt is equipped with a speed changing device to realize accurate control of the coke discharge rate. The speed changing device has a wide adjustment range and can adapt to the speed requirements of different production stages to ensure smooth connection between the semi-coke production process and the spiral semi-coke cooler.

[0017] The shown spiral semi-coke cooler drum has an inner drum and an outer drum, the outer drum has end sleeves at both ends, the bottom of the end sleeves is supported by a support frame, the outer drum body is between the two end sleeves, the outer drum body and the end sleeves are in a rotary sealing structure (using the rotary sealing of the prior art, such as a rotary sealing ring), the inner drum is connected to the end sleeves through fixed rods at both ends, the inner drum does not rotate, the outer drum body rotates under the drive of an external transmission structure, the inner wall of the outer drum body is fixed with multiple paddles, the paddles push the semi-coke towards the outlet, the outlet of the semi-coke is at the bottom of the tail end sleeve, the head end sleeve is provided with a feed inlet, the bottom end of the semi-coke conveying pipe 14 extends into the interior of the spiral semi-coke cooler from the feed inlet, a cooling water circulating pipe is arranged between the inner drum and the outer drum, the cooling water circulating pipe is around the inner drum, the inner drum is provided with spiral vanes 9 and longitudinal vanes 10, the cooling water inlet 12 and the cooling water outlet 11 of the cooling water circulating pipe are arranged at the tail end sleeve, the water inlet direction is opposite to the direction of the semi-coke spiral pushing. The cooling water circulating pipe contacts the semi-coke while not hindering the rotation of the outer drum. The mechanism for providing the rotation of the outer drum includes a support ring 7, a support wheel 15, a transmission wheel 16 and a driving motor 8, the driving motor 8 is placed at one side of the outer drum, the output shaft of the driving motor 8 is connected to the transmission wheel, the transmission wheel 16 and the support wheel 15 are in friction transmission, and the support ring 7 is rotationally supported and connected to the outer drum body. The driving motor can be placed at any side of the outer drum, the spiral vanes serve to accommodate high-temperature semi-coke, the high-temperature semi-coke is pushed by the paddles of the outer drum body, so that the high-temperature semi-coke moves towards the outlet direction of the semi-coke, and the longitudinal vanes ensure the uniform distribution and sufficient cooling of the high-temperature semi-coke in the drum. The cooling water enters from the cooling water inlet 12 of the tail end sleeve, indirectly contacts the semi-coke, and is completely opposite to the advancing direction of the semi-coke, forming a counterflow, and fully absorbing the sensible heat of the semi-coke through heat conduction, heat radiation and heat convection. The cooling water heated by absorbing heat flows out from the outer layer and enters a flash tank.

[0018] The shown flash tank is used for decompression evaporation of the heated cooling water in the cooling chamber, the water heated to about 150°C from the cooling chamber enters the flash tank, the pressure is reduced, and the high-temperature cooling water is quickly evaporated to form steam. The steam is introduced into a steam drum for further steam-water separation to produce high-quality low-pressure saturated steam, which is recycled into a mixed gas distribution chamber as raw material low-pressure saturated water vapor. When the mixed gas is distributed, the steam content in the mixed gas is increased to improve the quality of the products, especially the quality of the tar products. The system not only solves the problem of the source of steam in the mixed gas, saves a large amount of energy, and improves the product quality of the semi-coke furnace.

Claims

1. A coke dry quenching waste heat recovery system of a semi coke oven, comprising a semi coke oven, a burner, a mixing gas distribution chamber, a cooling chamber, wherein semi coke is transferred from the semi coke oven to the cooling chamber, characterized in that: The cooling chamber is water-cooled structure, the water-cooled pipeline outlet is connected to the flash tank, the flash tank is connected to the steam drum through a pipeline, the steam drum is internally provided with a steam-water separation element, the steam drum is provided with a water vapor outlet pipe and a condensed water outlet pipe, the water vapor outlet pipe is connected to the mixed gas distribution chamber, and the condensed water outlet pipe is connected to the cooling water inlet pipe through an air cooler; the cooling chamber is internally designed with a conveyor belt (2), a coke pushing arm (1), a coke storage hopper (4), a spiral semi-coke cooler (13) and a semi-coke baffle (6), the semi-coke baffle (6) and the coke pushing arm (1) are arranged at the bottom of the semi-coke furnace, the coke pushing arm (1) controls the opening size of the semi-coke baffle (6) to control the coke discharging rate, the conveyor belt (2) is arranged below the semi-coke baffle (6), the coke storage hopper (4) is arranged below the material dropping end of the conveyor belt (2) to receive the falling semi-coke, the bottom of the coke storage hopper (4) is connected with a semi-coke conveying pipe (14), the material in the semi-coke conveying pipe (14) flows by gravity, and the bottom end of the semi-coke conveying pipe (14) enters the spiral semi-coke cooler; the spiral semi-coke cooler (13) has an inner cylinder and an outer cylinder, end sleeves are arranged at the two ends of the outer cylinder, the end sleeves are supported by a support frame, the outer cylinder body is between the two end sleeves, a rotary sealing structure is arranged between the outer cylinder body and the end sleeves, the two ends of the inner cylinder are connected with the end sleeves through fixing rods, the inner cylinder does not rotate, the outer cylinder body rotates under the driving of an external transmission structure, a plurality of paddles are fixed to the inner wall of the outer cylinder body, the paddles push the semi-coke to move towards the outlet, the outlet of the semi-coke is at the bottom of the tail end sleeve, the head end sleeve is provided with a feeding port, the bottom end of the semi-coke conveying pipe (14) extends into the spiral semi-coke cooler from the feeding port, a cooling water circulating pipe is arranged between the inner cylinder and the outer cylinder, the cooling water circulating pipe is arranged around the inner cylinder, the inner cylinder is provided with spiral vanes (9) and longitudinal vanes (10), the cooling water inlet (12) and the cooling water outlet (11) of the cooling water circulating pipe are arranged at the tail end sleeve, and the water inlet direction is opposite to the semi-coke spiral pushing direction.

2. The semi-coke dry quenching waste heat recovery system according to claim 1, characterized in that: The conveyor belt (2) is designed as a horizontal type or an inclined type, the conveyor belt (2) has two, and the coke storage hopper (4) is designed between the two conveyor belts, and the two conveyor belts are oppositely operated.

3. The semi-coke dry quenching waste heat recovery system according to claim 1, characterized in that: The mechanism for providing rotating force for the outer cylinder includes a support ring (7), a support wheel (15), a transmission wheel (16) and a driving motor (8), the driving motor (8) is arranged on one side of the outer cylinder, the output shaft of the driving motor (8) is connected with the transmission wheel, the transmission wheel (16) is in friction transmission with the support wheel (15), and the support ring (7) is rotationally and supportingly connected with the outer cylinder body.

4. The semi-coke dry quenching waste heat recovery system according to claim 1, characterized in that: The steam-water separation element is a wire mesh and is provided with multiple layers of wire meshes.

5. The semi-coke dry quenching waste heat recovery system according to claim 1, characterized in that: A rotary valve (3) is connected between the coke storage hopper (4) and the semi-coke conveying pipe (14).

6. The semi-coke dry quenching waste heat recovery system according to claim 1, characterized in that: The oxygen of the mixed gas distribution chamber comes from a VPSA oxygen production device.

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