Coal gasification apparatus and method of controlling coal gasification reaction

Abstract

The present disclosure provides a coal gasification device and a method for controlling a coal gasification reaction, the coal gasification device comprising a furnace shell, the coal gasification device further comprising a coal gasification chamber and a medium-temperature reaction chamber which are in communication from top to bottom in the furnace shell; the coal gasification chamber is used for gasification of pulverized coal or coal water slurry to form high-temperature crude synthesis gas; the high-temperature crude synthesis gas enters the medium-temperature reaction chamber through a high-temperature crude synthesis gas outlet of the coal gasification chamber; the medium-temperature reaction chamber is used for mixed reaction of the high-temperature crude synthesis gas with industrial wastewater or waste gas, for treatment of the above-mentioned industrial wastewater or waste gas, and for formation of medium-temperature synthesis gas; the medium-temperature synthesis gas is discharged through a medium-temperature synthesis gas outlet of the medium-temperature reaction chamber; through the coal gasification device of the present disclosure, carbon conversion rate is effectively improved, effective gas components are improved, good effects are achieved in industrial wastewater treatment, CO2 recovery and the like, and beneficial effects of environmental friendliness, energy saving and emission reduction, cost reduction and benefit increase are brought.

Description

Technical Field

[0001] This invention belongs to the field of coal gasification technology, and specifically relates to a coal gasification device. Background Technology

[0002] my country is rich in coal resources, and coal is an important energy source. Many chemicals are derived from coal conversion products, making the clean utilization of coal a key research direction in China. Coal gasification is a process that converts solid fossil fuel coal into gaseous combustibles at high temperatures, and it is an important way to utilize coal efficiently and cleanly. In recent years, fluidized bed gasification technology has been widely adopted due to its advantages of fast reaction speed, high energy utilization rate, and low environmental pollution. This technology can achieve a coal conversion rate of 99%, with an effective gas content of 85-95%, and low coal and oxygen consumption per unit product, resulting in good economic benefits. Meanwhile, chemical production processes often generate waste liquids and gases, the discharge of which is restricted and the treatment costs are high. Therefore, under the global trend of environmental protection and energy conservation, developing equipment and methods to solve the problems of environmental pollution and energy waste caused by waste liquid / gas emissions in chemical processes has become an important issue that urgently needs to be optimized and solved.

[0003] Furthermore, coal gasification technology utilizes solid fossil fuels to generate gaseous combustibles under high temperature and pressure, representing a highly efficient and clean utilization method for coal. Fluidized bed gasifiers can produce high-temperature syngas with an effective gas composition of 85-95%, but also generate significant amounts of industrial waste liquid / gas. Given the global trend towards environmental protection and energy conservation, achieving efficient heat recovery, improving carbon conversion rates, enhancing the effective gas composition, and treating industrial waste liquid / gas within the same equipment is the future development direction. Summary of the Invention

[0004] In view of the above-mentioned problems existing in the prior art, this disclosure provides a coal gasification device that improves carbon conversion rate, effectively treats industrial wastewater, recovers CO2, and is environmentally friendly.

[0005] To achieve the above objectives, the technical solution adopted in the embodiments of the present invention is as follows:

[0006] On one hand, a coal gasification device includes a furnace shell, and the coal gasification device further includes a coal gasification chamber and a medium-temperature reaction chamber disposed within the furnace shell and connected from top to bottom; wherein, the coal gasification chamber is used to gasify pulverized coal or coal-water slurry to form high-temperature crude syngas; the high-temperature crude syngas enters the medium-temperature reaction chamber through the high-temperature crude syngas outlet of the coal gasification chamber; the medium-temperature reaction chamber is used to mix and react the high-temperature crude syngas with industrial wastewater or waste gas to treat the aforementioned industrial wastewater or waste gas and form medium-temperature syngas; the medium-temperature syngas is discharged through the medium-temperature syngas outlet of the medium-temperature reaction chamber.

[0007] In some embodiments of this disclosure, the intermediate-temperature reaction chamber includes a plurality of atomizing nozzles; the atomizing nozzles penetrate the furnace shell and are evenly distributed along the circumference of the furnace shell.

[0008] In some embodiments of this disclosure, the central axis of the atomizing nozzle is configured such that the atomizing nozzle is oriented toward the high-temperature crude syngas outlet.

[0009] In some embodiments of this disclosure, the atomizing nozzles are configured to be 4-80.

[0010] In some embodiments of this disclosure, the intermediate-temperature reaction chamber is configured with a water-cooled wall or a refractory brick structure; wherein the water-cooled wall is a coil type, a tube type, or a combination thereof.

[0011] In some embodiments of this disclosure, the coal gasification unit further includes a quench chamber and a waste boiler section; the quench chamber is connected to the medium-temperature reaction chamber via the medium-temperature syngas outlet; the waste boiler section is connected to the quench chamber via the quench chamber outlet of the quench chamber.

[0012] In some embodiments of this disclosure, the coal gasification unit further includes a quench chamber or waste boiler section, which is connected to the medium-temperature reaction chamber via the medium-temperature syngas outlet.

[0013] In some embodiments of this disclosure, the coal gasification device further includes a slag discharge chamber; the slag discharge chamber is connected to the quench chamber or the waste boiler section, and is used to discharge waste slag through the slag discharge port.

[0014] On the other hand, a method for controlling a coal gasification reaction, used in a coal gasification unit, the method comprising the following steps:

[0015] First step: Pulverized coal or coal-water slurry enters the coal gasification chamber for combustion or gasification reaction to produce high-temperature crude syngas. The high-temperature crude syngas enters the medium-temperature reaction chamber through the high-temperature crude syngas outlet.

[0016] The second step involves introducing industrial wastewater / exhaust gas into a medium-temperature reaction chamber. The wastewater / exhaust gas mixes and exchanges heat with the high-temperature crude syngas, forming medium-temperature syngas. If the wastewater is being treated, the high-temperature crude syngas utilizes its own heat energy to decompose the organic matter in the wastewater, achieving the purpose of wastewater treatment. If the exhaust gas is being treated, the high-temperature crude syngas reacts with the exhaust gas components at a medium temperature, achieving the purpose of exhaust gas treatment.

[0017] Third step: The medium-temperature syngas enters the quench chamber or the waste boiler section, the temperature of the medium-temperature syngas decreases, the heat dissipation is carried away by the quench chamber or recycled by the waste boiler section, and the ash is discharged from the slag discharge port.

[0018] In some embodiments of this disclosure, the high-temperature crude syngas includes molten ash particles and carbonaceous ash; wherein the molten ash particles are thrown toward the water-cooled wall of the gasification chamber under the action of inertial force and form a liquid slag film.

[0019] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0020] The coal gasification device of this invention introduces a medium-temperature reaction section based on the existing fluidized bed coal gasification process. By utilizing the heat of the medium-temperature syngas, the waste gas / waste liquid and residual carbon undergo a secondary reaction in the medium-temperature reaction section, thereby improving the carbon conversion rate, improving the effective gas composition, and simultaneously treating industrial wastewater and recovering carbon dioxide.

[0021] In addition, the coal gasification device of the invention embodiment can effectively prevent ash accumulation in the waste boiler, achieving the goals of environmental friendliness, energy conservation and emission reduction, cost reduction and efficiency improvement. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the structure of a coal gasification device according to an embodiment of the present invention;

[0023] Figure 2 This is a partial structural schematic diagram of a coal gasification device according to an embodiment of the present invention;

[0024] Figure 3 This is a top view of the intermediate-temperature reaction chamber of the coal gasification device according to an embodiment of the present invention;

[0025] Figure 4 This is a top view of the intermediate-temperature reaction chamber of the coal gasification device according to an embodiment of the present invention;

[0026] Figure 5 This is a flowchart of a method for controlling coal gasification reaction according to an embodiment of the present invention.

[0027] Explanation of reference numerals in the attached figures

[0028] 101-Gasification burner; 102-Furnace shell; 103-Gasification chamber;

[0029] 104 - High-temperature crude syngas outlet; 105 - Medium-temperature reaction chamber; 106 - Atomizing nozzle;

[0030] 107 - Intermediate temperature syngas outlet; 108 - Quenching chamber; 109 - Quenching chamber syngas outlet;

[0031] 110 - Quenching chamber outlet; 111 - Slag discharge chamber; 112 - Slag discharge port;

[0032] 113 - Water-cooled wall of the intermediate temperature reaction chamber; Detailed Implementation

[0033] The specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings, but these are not intended to limit the scope of the invention. To enable those skilled in the art to better understand the technical solutions of this disclosure, the present disclosure will be described in detail below with reference to the accompanying drawings and specific embodiments. The embodiments of the present disclosure will be further described in detail below with reference to the accompanying drawings and specific embodiments, but these are not intended to limit the scope of the disclosure.

[0034] All terms used in this disclosure (including technical or scientific terms) have the same meaning as understood by one of ordinary skill in the art to which this disclosure pertains, unless otherwise specifically defined. It should also be understood that terms defined in a general dictionary, such as a dictionary, should be interpreted as having a meaning consistent with their meaning in the context of the relevant art, and not as having an idealized or highly formalized meaning, unless expressly defined herein.

[0035] Techniques, methods, and equipment known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and equipment should be considered part of the specification.

[0036] Currently, fluidized bed gasifiers typically produce high-temperature syngas with an effective gas composition of 85-95%, while also generating large amounts of industrial waste liquid / gas. Therefore, under the global trend of environmental protection and energy conservation, achieving efficient heat recovery, improving carbon conversion rate, enhancing the effective gas composition, and improving the efficiency of industrial waste liquid / gas treatment will become major future demands. To this end, this invention provides the following design scheme.

[0037] On the one hand, see Figure 1 A coal gasification device includes a furnace shell 102. The coal gasification device further includes a coal gasification chamber 103 and a medium-temperature reaction chamber 105 disposed inside the furnace shell 102 and connected from top to bottom. The coal gasification chamber 103 is used to gasify pulverized coal or coal-water slurry to form high-temperature crude syngas. The high-temperature crude syngas enters the medium-temperature reaction chamber 105 through the high-temperature crude syngas outlet 104 of the coal gasification chamber 103. The medium-temperature reaction chamber 105 is used to mix and react the high-temperature crude syngas with industrial wastewater or waste gas to treat the aforementioned industrial wastewater or waste gas and form medium-temperature syngas. The medium-temperature syngas is discharged through the medium-temperature syngas outlet 107 of the medium-temperature reaction chamber 105. In this embodiment, pulverized coal or coal-water slurry enters the gasification chamber 103 through the gasification burner 101. After forming high-temperature crude syngas, the high-temperature crude syngas enters the medium-temperature reaction chamber 105. In the medium-temperature reaction chamber 105, it reacts with industrial wastewater or waste gas to treat industrial wastewater and recover carbon dioxide. At the same time, the excess heat generated is reused, solving the problem of ineffective treatment of wastewater and carbon dioxide generated in industrial production processes and meeting future environmental protection requirements.

[0038] In one embodiment, combined with Figures 2 to 4 The intermediate-temperature reaction chamber 105 includes multiple atomizing nozzles 106; the atomizing nozzles 106 penetrate the furnace shell 102 and are evenly distributed along the circumference of the furnace shell 102. This arrangement improves the thorough mixing of high-temperature crude syngas with industrial wastewater or waste gas in the intermediate-temperature reaction chamber 105, and enables a highly efficient secondary reaction.

[0039] In one embodiment, combined with Figure 3 and Figure 4 The central axis of the atomizing nozzle 106 is configured to face the high-temperature crude syngas outlet 104. This configuration ensures that when industrial wastewater or exhaust gas enters the intermediate-temperature reaction chamber 105 through the atomizing nozzle 106, it directly faces the high-temperature crude syngas outlet 104, allowing for thorough mixing and improving the efficiency of the secondary reaction. Specifically, in this embodiment, the angle between the central axis of the atomizing nozzle 106 and the axis of the intermediate-temperature reaction chamber 105 can be set to 0°–90°, or the angle between the central axis of the atomizing nozzle 106 and the tangent direction of the furnace shell 102 can be set to 0°–90°. The specific angle can be adjusted according to the state of the high-temperature crude syngas entering the intermediate-temperature reaction chamber 105 and the composition of the industrial wastewater or exhaust gas; no specific limitation is made here.

[0040] In one embodiment, combined with Figure 3 and Figure 4 The number of atomizing nozzles 106 can be set from 4 to 80. The number of atomizing nozzles 106 can be set according to the amount of industrial wastewater or exhaust gas to be treated and the size of the medium-temperature reaction chamber 105. There is no limit here, and it can be adjusted according to the actual situation.

[0041] In one embodiment, see Figure 2 The intermediate-temperature reaction chamber 105 is equipped with a water-cooled wall or refractory brick structure (not shown in the figure); wherein the water-cooled wall is a coil type, a tube type, or a combination thereof. This arrangement effectively reduces the damage to the furnace shell 102 caused by the high-temperature crude syngas, extends the service life of the furnace shell 102, and reduces or minimizes the maintenance cycle. In this embodiment, the water-cooled wall is the intermediate-temperature reaction chamber water-cooled wall 113.

[0042] In one embodiment, see Figure 1The coal gasification unit further includes a quench chamber 108 and a waste boiler section (not shown in the figure); the quench chamber 108 is connected to the medium-temperature reaction chamber 105 through a medium-temperature syngas outlet 107; the waste boiler section is connected to the quench chamber 108 through a quench chamber outlet 110. In this embodiment, the quench chamber 108 is used for washing and cooling the medium-temperature syngas, and for separating the washed medium-temperature syngas. The separated medium-temperature syngas is used to prepare for subsequent reactions; for example, a portion enters the waste boiler section for further washing and separation, or a portion is directly discharged through the quench chamber syngas outlet 109.

[0043] In one embodiment, see Figure 1 The coal gasification unit also includes a quench chamber 108 or a waste boiler section, connected to the medium-temperature reaction chamber 105 via a medium-temperature syngas outlet 107. In this embodiment, the quench chamber 108 or the waste boiler section is selected according to the needs of subsequent reactions to reduce unnecessary reaction processes. For example, after the syngas temperature drops from a high temperature (1300–1700°C) to a medium temperature (800–1200°C), the ash gradually solidifies and loses its stickiness. This allows for direct separation based on the current medium-temperature state, even with only the quench chamber 108, and the separated medium-temperature syngas and ash are transported to the next process step for further solid-liquid separation. This configuration is mainly selected based on the specific application scenario, such as washing and further cooling the medium-temperature syngas.

[0044] In one embodiment, see Figure 1 The coal gasification unit also includes a slag discharge chamber 111; the slag discharge chamber 111 is connected to the quench chamber 108 or the waste boiler section, and is used to discharge waste slag through the slag discharge port 112. This arrangement prevents environmental pollution during the slag discharge process.

[0045] On the other hand, a method for controlling the coal gasification reaction, see [link to relevant documentation]. Figure 5 It is used in a coal gasification unit, and the method includes the following steps:

[0046] The first step involves pulverized coal or coal-water slurry entering the coal gasification chamber 103 for combustion or gasification reaction, producing high-temperature crude syngas. The high-temperature crude syngas then enters the medium-temperature reaction chamber 105 through the high-temperature crude syngas outlet 104. In this step, solid fuel coal is mixed with an oxidant and reacted under high temperature and pressure to generate high-temperature gasification products. The main components are high-temperature crude syngas, molten ash, and carbon-containing coal ash particles. The carbon content of the carbon-containing coal ash particles is generally between 5% and 50%. In subsequent steps, the high-temperature gasification products are effectively separated.

[0047] The second step involves introducing industrial wastewater / exhaust gas into a medium-temperature reaction chamber 105. The wastewater / exhaust gas mixes and exchanges heat with the high-temperature crude syngas, forming medium-temperature syngas. If treating wastewater, the high-temperature crude syngas utilizes its own heat energy to decompose the organic matter in the wastewater, achieving wastewater treatment. If treating exhaust gas, the high-temperature crude syngas reacts with the exhaust gas components at a medium temperature, achieving exhaust gas treatment. In this step, industrial wastewater typically contains organic matter. Through mixing and reaction with the high-temperature crude syngas, the organic matter is decomposed, thereby degrading the organic matter (e.g., toxic and harmful organic compounds such as phenols) contained in the industrial wastewater / exhaust gas, achieving purification, and ensuring that the substances obtained from the reaction meet environmentally friendly requirements.

[0048] In this step, the waste gas / industrial wastewater enters through the atomizing nozzle 106 on the side of the medium-temperature reaction chamber 105 and mixes with the high-temperature dust-laden crude syngas entering from the high-temperature crude syngas outlet 104 of the gasification chamber 103. This process completely decomposes the organic matter in the waste gas / industrial wastewater, rendering it harmless. The industrial waste gas (CO2, etc.) can continue to react with the residual carbon in the coal ash carried by the syngas to further improve the carbon conversion rate. At the same time, a shift reaction is carried out to optimize the composition of the syngas.

[0049] The third step: The medium-temperature syngas enters the quench chamber 108 or the waste boiler section. The temperature of the medium-temperature syngas decreases, and the heat dissipation is carried away by the quench chamber 108 or recycled by the waste boiler section. Ash and slag are discharged through the slag discharge port 112. Since the industrial wastewater / waste gas has been preliminarily purified in the previous step, waste heat can be utilized in this step, and further gas-liquid separation of the medium-temperature syngas can be performed, preparing for subsequent applications. For example, the heat contained in the gaseous portion can be used as a heat source for heating circulation; the liquid portion can be used as industrial circulating water after removing solid impurities, thereby saving operating costs. In this step, because the high-temperature crude syngas has its temperature reduced in the medium-temperature reaction chamber 105, generally from 1300–1700℃ to below 1200℃, ash accumulation can be prevented or reduced after entering the quench chamber 108 or the waste boiler section.

[0050] In one embodiment, the high-temperature crude syngas may include molten ash particles and carbonaceous ash; wherein the molten ash particles are thrown towards the water-cooled wall of the gasification chamber 103 under the action of inertial force, forming a liquid slag film. In this embodiment, the high-temperature crude syngas outlet 104 enters the intermediate-temperature reaction chamber 105 for separation and cooling.

[0051] Furthermore, although illustrative embodiments are described herein, the scope includes any and all embodiments having equivalent elements, modifications, omissions, combinations (e.g., combinations of schemes across various embodiments), adjustments, or alterations based on this disclosure. Elements in the claims are to be interpreted broadly based on the language used in the claims and are not limited to the examples described herein or during the duration of this application. Moreover, the steps of the disclosed methods can be modified in any way, including by reordering steps or inserting or deleting steps. Therefore, the description is intended to be merely illustrative, and the true scope is indicated by the following claims and their full equivalents.

[0052] The above description is intended to be illustrative and not restrictive. For example, the examples (or one or more aspects thereof) described above can be used in combination with each other. Other embodiments can be used by those skilled in the art after reading the above description. Moreover, various features can be combined together in the above detailed description to simplify this disclosure. This should not be construed as meaning that any disclosed feature not claimed is essential to any claim. Therefore, the following claims are incorporated into the detailed description as examples or embodiments, wherein each claim is itself a separate embodiment, and these embodiments can be contemplated to be combined with each other in various combinations or substitutions. The scope of the invention should be determined with reference to the appended claims and the full scope of the equivalents conferred by those claims.

Claims

1. A method for controlling coal gasification reaction, using a coal gasification device, characterized in that, the coal gasification device comprises a furnace shell, and further comprises a coal gasification chamber and a medium-temperature reaction chamber which are connected in sequence from top to bottom in the furnace shell; wherein, the coal gasification chamber is used for gasification of pulverized coal or coal water slurry to form high-temperature crude synthesis gas; the high-temperature crude synthesis gas enters the medium-temperature reaction chamber through a high-temperature crude synthesis gas outlet of the coal gasification chamber; the medium-temperature reaction chamber is used for mixing reaction of the high-temperature crude synthesis gas with industrial waste water or industrial waste gas, treatment of the industrial waste water or industrial waste gas, and formation of medium-temperature synthesis gas; the medium-temperature synthesis gas is discharged through a medium-temperature synthesis gas outlet of the medium-temperature reaction chamber; the coal gasification device further comprises a quenching chamber and a waste boiler section, the quenching chamber is connected with the medium-temperature reaction chamber through the medium-temperature synthesis gas outlet, and the waste boiler section is connected with the quenching chamber through a quenching chamber outlet of the quenching chamber; or the coal gasification device further comprises a quenching chamber or a waste boiler section, which is connected with the medium-temperature reaction chamber through the medium-temperature synthesis gas outlet; the medium-temperature reaction chamber comprises a plurality of atomizing nozzles; the atomizing nozzles penetrate through the furnace shell and are uniformly distributed along the circumference of the furnace shell; an included angle between a central axis of the atomizing nozzle and an axis of the medium-temperature reaction chamber, or an included angle between the central axis of the atomizing nozzle and a tangent direction of a circumferential surface of the furnace shell, is adjusted according to a state of the high-temperature crude synthesis gas entering the medium-temperature reaction chamber and a composition of the industrial waste water or industrial waste gas; the method comprises the following steps: a first step: pulverized coal or coal water slurry enters the coal gasification chamber to perform gasification reaction, thereby generating high-temperature crude synthesis gas, which enters the medium-temperature reaction chamber through the high-temperature crude synthesis gas outlet; a carbon content of carbon-containing coal ash particles contained in the high-temperature crude synthesis gas is 5%-50%; a second step: industrial waste water or industrial waste gas is introduced into the medium-temperature reaction chamber to mix and exchange heat with the high-temperature crude synthesis gas, thereby forming medium-temperature synthesis gas; through the mixing reaction with the high-temperature crude synthesis gas, organic matters contained in the industrial waste water or industrial waste gas are degraded, residual carbon in the industrial waste water or industrial waste gas and the carbon-containing coal ash particles is subjected to secondary reaction in the medium-temperature reaction chamber, thereby improving carbon conversion rate; after the temperature of the high-temperature crude synthesis gas is reduced from high temperature to medium temperature, the ash gradually solidifies and loses stickiness; a high-temperature temperature range is 1300℃-1700℃, and a medium-temperature temperature range is 800℃-1200℃; a third step: the medium-temperature synthesis gas enters the quenching chamber or the waste boiler section, the temperature of the medium-temperature synthesis gas is reduced, heat dissipation is taken away by the quenching chamber or recovered and utilized by the waste boiler section, and ash is discharged through an ash discharge port.

2. The method of claim 1, wherein, The atomizing nozzles are arranged to face the high-temperature crude synthesis gas outlet.

3. The method of claim 1, wherein, The atomizing nozzles are arranged in a number of 4-80.

4. The method of claim 1, wherein, The medium-temperature reaction chamber is in a water-cooled wall structure or a refractory brick structure; wherein, the water-cooled wall is in a coil type, a column type or a combination thereof.

5. The method of claim 1, wherein, Further comprising an ash discharge chamber; the ash discharge chamber is connected with the quenching chamber or the waste boiler section, and is used for discharging waste ash through an ash discharge port.

Images