Gasification device and method for heating asphalt

Abstract

A gasification device and method for heating asphalt, the device mainly comprises a coal powder storage tank, a ventilator, a volumetric screw conveyor, an ejector, a gasifier burner, a gasifier, an asphalt mixing station device, a slag crusher, a slag tank and a slag remover, the method comprises the following steps: dry coal powder is fed into a normal pressure gasifier, and a high-temperature gasification reaction occurs with air to generate a raw coal gas mainly composed of CO and H2, and the raw coal gas is fed into the asphalt mixing station device, while the ash and slag are in a molten state during the gasification process, flow out from the lower part of the gasifier, and are discharged through a slag discharge unit; the gasifier is the core equipment of the whole device, and has the characteristics of ultra-high temperature gasification and high slag capture rate through a unique design; the device of the present invention is used for heating asphalt, and has the characteristics of high carbon conversion rate and high slag capture rate, and can improve the economy and environmental performance of the device.

Description

Technical Field

[0001] The present invention relates to a gasification device and process for heating asphalt, and in particular to a gasification device and method for heating asphalt. Background Art

[0002] Asphalt mixing plant, also known as asphalt concrete mixing plant, refers to a complete set of equipment used for mass production of asphalt concrete. It can produce asphalt mixture, modified asphalt mixture, and colored asphalt mixture. It is necessary equipment for the construction of highways, grade highways, municipal roads, airports, and ports. Highway asphalt mixing plant is not only a very important construction equipment in asphalt pavement construction, but also the equipment that pollutes the environment the most in highway construction. Asphalt mixing plant will produce a large amount of harmful substances in the process of burning fuel, including carbon dioxide, sulfur dioxide, and nitrogen oxides. These harmful substances have extremely serious harm to the natural environment. It is necessary to adopt a series of energy-saving and emission-reduction technical measures to effectively reduce the harmful substances emitted by asphalt mixing plant, so as to achieve the goal of reducing harm to the environment.

[0003] The fuel of traditional asphalt mixing plants is coal powder and heavy oil, which are burned directly, causing a lot of environmental problems. This year, with the increasing requirements for environmental protection in my country, some asphalt mixing plants use clean combustion such as natural gas. However, due to the high price of natural gas, the cost of asphalt has risen sharply, which some companies cannot afford.

[0004] Coal gasification technology can transform a heating method that seriously pollutes the environment into a cleaner heating method, effectively reducing the pollution of coal to the environment. Coal gasification technology is generally divided into two gasification methods: atmospheric pressure gasification and pressurized gasification. The principle of coal gasification is mainly to use gasification agents such as air, oxygen and steam to react with coal under normal pressure or pressure and certain temperature conditions to generate coal gas. The main components of coal gas are combustible gases such as hydrogen and carbon monoxide, so the combustion efficiency of coal is higher after gasification. Moreover, during the gasification process, sulfur and nitrogen elements can be removed from coal, as well as ash and slag. Therefore, the coal gas after coal gasification is a clean energy source. After combustion, the degree of pollution to the natural environment is very small, which is beneficial to environmental protection.

[0005] Due to the characteristics of the asphalt mixing plant industry, the gasification device must have low investment, fast start and stop, and safe and reliable operation. Therefore, it is necessary to choose the atmospheric pressure gasification method. At present, atmospheric pressure gasification devices have been used in asphalt mixing plants, but they have not solved the problem caused by the low gasification intensity of atmospheric pressure gasifiers, and ultimately exposed problems such as low carbon conversion rate and insufficient slag capture rate.

[0006] In view of the problems existing in the existing devices, the present invention develops an ultra-high temperature, high slag capture rate gasification device and process, thereby further improving the gasification technology level used in asphalt mixing plants and improving the economy and environmental performance of the device. Summary of the invention

[0007] In order to overcome the problems existing in the above-mentioned prior art, the purpose of the present invention is to provide a gasification device and method for heating asphalt, wherein the gasification device is a gasification device with high carbon conversion rate and high slag capture rate. Coal powder is gasified in the gasifier, and the generated high-temperature synthesis gas is fed into the burner of the asphalt mixing station, and most of the ash is removed in the gasifier.

[0008] In order to achieve the above object, the present invention adopts the following technical scheme:

[0009] A gasification device for heating asphalt, comprising a pulverized coal storage tank 2, the inlet of the pulverized coal storage tank 2 is connected to an exhaust filter 1 and a pulverized coal pipeline, the outlet of the pulverized coal storage tank 2 is connected to an inlet of an injector 5 through a ventilator 3 and a volumetric screw conveyor 4, the other inlet of the injector 5 is connected to an air pipeline, the outlet of the injector 5 is connected to a gasifier 7 through a gasifier burner 6 on the top of the gasifier 7, a separate pipeline is provided on the gasifier burner 6 for connecting to the air pipeline, the reaction zone of the gasifier 7 is surrounded by a water-cooled wall, and a heat-resistant material with a temperature resistance of more than 2000°C is laid on the water-cooled wall; asphalt The heat transfer oil outlet of the mixing station device 8 is connected to the water-cooled wall inlet of the gasifier 7 through the heat transfer oil pump 9. The water-cooled wall outlet of the gasifier 7 is connected to the asphalt mixing station device 8 to form a heat transfer oil loop. The heat transfer oil cooled by the asphalt mixing station device 8 is used to cool the water-cooled wall of the gasifier 7. The synthesis gas outlet of the gasifier 7 is connected to the synthesis gas inlet of the asphalt mixing station device 8. The high-temperature synthesis gas generated by the gasification reaction in the gasifier 7 heats the asphalt in the asphalt mixing station device 8. The ash outlet of the gasifier 7 is connected to the slag crusher 10, the slag pot 11 and the slag scoop 12 in sequence to collect and send out the ash.

[0010] The gasifier burner 6 is equipped with a guide vane to achieve premixing of coal powder and air in the gasifier burner 6, and swirl through the guide vane to ensure that ash can be captured in large quantities by the wall of the gasifier 7, while the wall temperature of the gasifier 7 does not exceed the temperature.

[0011] The heat-resistant material capable of withstanding temperatures above 2000° C. is a magnesium-aluminum refractory material.

[0012] The working method of the gasification device for heating asphalt is as follows: coal powder is sent into the coal powder storage tank 2, and the coal powder carried by the exhaust gas is collected and returned to the coal powder storage tank 2 through the exhaust filter 1. The coal powder in the coal powder storage tank 2 is quantitatively sent to the ejector 5 through the ventilator 3 and the volumetric screw conveyor 4, and is carried by the air into the gasifier burner 6. At the same time, more air enters the gasifier burner 6 from a separate pipeline for staged gasification. After the coal powder and air are mixed in the gasifier burner 6, they are sent to the gasifier 7 for high-temperature gasification reaction. The water-cooled wall of the gasifier 7 is cooled by heat transfer oil. The heated heat transfer oil is sent to the asphalt mixing station device 8 for cooling, and then sent to the water-cooled wall of the gasifier 7 through the heat transfer oil pump 9 to cool the water-cooled wall. The ash produced by the gasifier 7 is crushed by the slag crusher 10, enters the slag tank 11, and then enters the slag scooper 12 to collect and send the ash; the high-temperature synthesis gas produced by the gasifier 7 is sent to the asphalt mixing station device 8 through the lower pipeline of the gasifier to heat the asphalt.

[0013] Compared with the prior art, the present invention has the following advantages:

[0014] 1. In order to achieve high carbon conversion rate and high slag capture rate of the gasification device, the design concept of "using slag to resist slag" of the traditional entrained flow gasifier was first changed. By selecting new high-temperature resistant refractory materials, the maximum operating temperature of the gasifier was increased by about 500°C, further accelerating the gasification reaction speed while ensuring the fusibility of the slag.

[0015] 2. The dry pulverized coal is transported by a volumetric screw conveyor 4, which can stably transport and accurately measure the amount of pulverized coal fed into the gasifier 7, thus avoiding the use of other expensive instruments.

[0016] 3. The pulverized coal is mixed with air in the injector 5. The injector ensures that the air and pulverized coal are evenly mixed and stably transported to the burner 6 of the gasifier.

[0017] 4. Air enters the gasifier burner 6 through the ejector 5 and a separate pipeline for staged gasification to ensure uniform temperature distribution in the gasifier 6. The burner design of the gasifier allows the pulverized coal and air to be premixed, swirled and staged for gasification, thereby increasing the residence time of the pulverized coal in the gasifier and further making the temperature field in the gasifier uniform. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the overall structure of the device of the present invention. DETAILED DESCRIPTION

[0019] The present invention will be further described in detail below in conjunction with the accompanying drawings.

[0020] like Figure 1As shown, the present invention is a gasification device for heating asphalt, including a pulverized coal storage tank 2, the inlet of the pulverized coal storage tank 2 is connected to an exhaust filter 1 and a pulverized coal pipeline, the outlet of the pulverized coal storage tank 2 is connected to an inlet of an injector 5 through a ventilator 3 and a volumetric screw conveyor 4, the other inlet of the injector 5 is connected to an air pipeline, the outlet of the injector 5 is connected to a gasifier 7 through a gasifier burner 6 on the top of the gasifier 7, a separate pipeline is provided on the gasifier burner 6 for connecting to the air pipeline, the reaction zone of the gasifier 7 is surrounded by a water-cooled wall, and a heat-resistant material with a temperature resistance of more than 2000°C is laid on the water-cooled wall The heat transfer oil outlet of the asphalt mixing station device 8 is connected to the water-cooled wall inlet of the gasifier 7 through the heat transfer oil pump 9. The water-cooled wall outlet of the gasifier 7 is connected to the asphalt mixing station device 8 to form a heat transfer oil loop. The heat transfer oil cooled by the asphalt mixing station device 8 is used to cool the water-cooled wall of the gasifier 7. The synthesis gas outlet of the gasifier 7 is connected to the synthesis gas inlet of the asphalt mixing station device 8. The high-temperature synthesis gas generated by the gasification reaction in the gasifier 7 heats the asphalt in the asphalt mixing station device 8. The ash outlet of the gasifier 7 is connected to the slag crusher 10, the slag pot 11 and the slag scooping machine 12 in sequence to collect and send out the ash.

[0021] The dry pulverized coal is transported by a volumetric screw conveyor 4, which can stably transport and accurately measure the amount of pulverized coal fed into the gasifier 7, thereby avoiding the use of other expensive instruments.

[0022] The pulverized coal is mixed with air in the injector 5 , which ensures that the air and pulverized coal are mixed evenly and are stably transported to the burner 6 of the gasifier.

[0023] The air enters the gasifier burner 6 through the ejector 5 and a separate pipeline, and is gasified in stages to ensure uniform temperature distribution in the gasifier 6 .

[0024] As a preferred embodiment of the present invention, the gasifier burner 6 is equipped with a guide vane to achieve premixing of coal powder and air in the gasifier burner 6, and swirl through the guide vane to ensure that ash can be captured in large quantities by the wall of the gasifier 7, and at the same time the wall temperature of the gasifier 7 does not exceed the temperature.

[0025] As a preferred embodiment of the present invention, the heat-resistant material capable of withstanding temperatures above 2000° C. is a magnesium-aluminum refractory material.

[0026] The working method of the gasification device for heating asphalt described in the present invention is as follows: coal powder is sent into the coal powder storage tank 2, and the coal powder carried by the exhaust gas is collected and returned to the coal powder storage tank 2 through the exhaust filter 1. The coal powder in the coal powder storage tank 2 is quantitatively sent to the ejector 5 through the ventilator 3 and the volumetric screw conveyor 4, and is carried by the air into the gasifier burner 6. At the same time, more air enters the gasifier burner 6 from a separate pipeline for graded gasification. After the coal powder and air are mixed in the gasifier burner 6, they are sent to the gasifier 7 for high-temperature gasification reaction. The water-cooled wall of the gasifier 7 is cooled by heat transfer oil. The heated heat transfer oil is sent to the asphalt mixing station device 8 for cooling, and then sent to the water-cooled wall of the gasifier 7 through the heat transfer oil pump 9 to cool the water-cooled wall. The ash generated by the gasifier 7 is crushed by the slag crusher 10, enters the slag tank 11, and then enters the slag scoop 12 to collect and send the ash; the high-temperature synthesis gas generated by the gasifier 7 is sent to the asphalt mixing station device 8 through the lower pipeline of the gasifier to heat the asphalt.

[0027] The present invention discloses a gasification device and method for heating asphalt. Compared with the existing gasification device, the device adopts a volumetric screw conveyor in combination with an ejector to ensure the stability of the conveying and the accuracy of the measurement. The design of the gasifier and the burner of the gasifier realizes the premixing, cyclone and graded gasification of oxygen and coal powder. Through the optimization of the structure and the selection of refractory materials, the temperature of the gasification reaction in the gasifier is about 500°C higher than that of the existing fluidized bed gasifier. Through the present invention, the gasification device has the characteristics of high carbon conversion rate and high slag capture rate compared with the existing device, improves the economy and environmental protection performance of the device, and thus can improve the overall technical level of the asphalt mixing plant.

Claims

1. A gasification device for heating asphalt, comprising a pulverized coal storage tank (2), characterized in that: The inlet of the pulverized coal storage tank (2) is connected to the exhaust filter (1) and the pulverized coal pipeline, the outlet of the pulverized coal storage tank (2) is connected to one inlet of the ejector (5) through the ventilator (3) and the volumetric screw conveyor (4), the other inlet of the ejector (5) is connected to the air pipeline, the outlet of the ejector (5) is connected to the gasifier (7) through the gasifier burner (6) at the top of the gasifier (7), a separate pipeline is provided on the gasifier burner (6) for connecting to the air pipeline, the reaction zone of the gasifier (7) is surrounded by a water-cooled wall, and a heat-resistant material with a temperature resistance of more than 2000°C is laid on the water-cooled wall; the heat transfer oil outlet of the asphalt mixing station device (8) is connected to the gasifier (7) through the gasifier burner (6) at the top of the gasifier (7). The inlet is connected to the water-cooled wall inlet of the gasifier (7) through a heat transfer oil pump (9), and the water-cooled wall outlet of the gasifier (7) is connected to the asphalt mixing station device (8) to form a heat transfer oil loop, and the water-cooled wall of the gasifier (7) is cooled by the heat transfer oil cooled by the asphalt mixing station device (8); the synthesis gas outlet of the gasifier (7) is connected to the synthesis gas inlet of the asphalt mixing station device (8), and the high-temperature synthesis gas generated by the gasification reaction in the gasifier (7) heats the asphalt in the asphalt mixing station device (8); the ash outlet of the gasifier (7) is connected to the slag crusher (10), the slag tank (11) and the slag scooping machine (12) in sequence, so that the ash is collected and sent out; The gasifier burner (6) is provided with a guide vane to achieve premixing of coal powder and air in the gasifier burner (6) and to achieve swirling flow through the guide vane, thereby ensuring that ash can be captured in large quantities by the wall of the gasifier (7) and that the wall temperature of the gasifier (7) does not exceed the temperature; The dry pulverized coal is transported by a volumetric screw conveyor (4), which is capable of stable transportation and accurate metering of the amount of pulverized coal fed into the gasifier (7); The pulverized coal is mixed with air in the injector (5), and the injector ensures that the air and pulverized coal are mixed evenly and stably transported to the burner (6) of the gasifier; The heat-resistant material capable of withstanding temperatures above 2000°C is a magnesium-aluminum refractory material; The air enters the gasifier burner (6) through the ejector (5) and a separate pipeline, and is gasified in stages, thereby ensuring uniform temperature distribution in the gasifier (7).

2. The working method of the gasification device for heating asphalt according to claim 1, characterized in that: The pulverized coal is fed into a pulverized coal storage tank (2), and the pulverized coal carried by the exhaust gas is collected by an exhaust gas filter (1) and returned to the pulverized coal storage tank (2). The pulverized coal in the pulverized coal storage tank (2) is quantitatively fed into an ejector (5) through a ventilator (3) and a volumetric screw conveyor (4), and is carried by air into a gasifier burner (6). At the same time, more air enters the gasifier burner (6) from a separate pipeline for staged gasification. After the pulverized coal and air are mixed in the gasifier burner (6), they are fed into a gasifier (7) for a high-temperature gasification reaction. The water-cooled wall of the gasifier (7) is cooled by heat transfer oil. The heated heat transfer oil is sent to the asphalt mixing station device (8) for cooling, and then sent to the water-cooled wall of the gasifier (7) through a heat transfer oil pump (9) to cool the water-cooled wall. The ash produced by the gasifier (7) is crushed by a slag crusher (10) and enters a slag tank (11), and then enters a slag scooping machine (12) to collect and send out the ash. The high-temperature synthesis gas produced by the gasifier (7) is sent to the asphalt mixing station device (8) through a pipeline at the bottom of the gasifier to heat the asphalt.

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