阅读说明：本技术 一种耦合微波技术的化学链燃烧定向脱硫工艺及装置 (Microwave technology-coupled chemical-looping combustion directional desulfurization process and device ) 是由 罗明 董宇航 张海燕 覃艳军 周伦正 钱黎黎 于 2021-03-30 设计创作，主要内容包括：本发明提供了一种耦合微波技术的化学链燃烧定向脱硫工艺及装置,通过微波频率使固体燃料进行脱硫反应,脱硫之后的固体燃料进入足氧燃料反应器,产生的含硫气体单独或者与流化介质混合后进入贫氧燃料反应器内；脱硫之后的固体燃料与进入足氧燃料反应器内的流化介质发生汽化反应后,与载氧体在足氧燃料反应器中进行还原反应；通过控制进入贫氧燃料反应器载氧体的进入量,从而控制贫氧燃料反应器内的过氧系数R；在贫氧燃料反应器中,含硫气体与未反应的载氧体生成金属硫化物,金属硫化物与剩余的载氧体在空气反应器中使失氧的载氧体恢复为含有晶格氧的载氧体。本发明实现从源头脱硫,使燃料反应器中产生的CO-(2)被捕集后无需进一步脱硫。(The invention provides a microwave technology-coupled chemical looping combustion directional desulfurization process and a microwave technology-coupled chemical looping combustion directional desulfurization device, wherein a solid fuel is subjected to desulfurization reaction through microwave frequency, the desulfurized solid fuel enters a sufficient oxygen fuel reactor, and the generated sulfur-containing gas enters an oxygen-deficient fuel reactor independently or after being mixed with a fluidizing medium; after the desulfurized solid fuel and the fluidized medium entering the oxygen-enriched fuel reactor are subjected to vaporization reaction, the desulfurized solid fuel and the oxygen carrier are in the oxygen-enriched fuel reactorCarrying out reduction reaction; controlling the oxygen peroxide coefficient R in the oxygen-deficient fuel reactor by controlling the entering amount of the oxygen carrier entering the oxygen-deficient fuel reactor; in an oxygen-deficient fuel reactor, the sulfur-containing gas and unreacted oxygen carrier form metal sulfides, which, together with the remaining oxygen carrier, restore the oxygen carrier, which is deprived of oxygen, to an oxygen carrier containing lattice oxygen in an air reactor. The invention realizes the source desulfurization and leads CO generated in the fuel reactor to be 2 No further desulfurization is required after capture.)

1. A microwave technology-coupled chemical looping combustion directional desulfurization process is characterized by comprising the following steps:

and (3) microwave desulfurization: mixing solid fuel with H₂Adding the solid fuel into a microwave reactor (1), carrying out desulfurization reaction on the solid fuel through microwave frequency, enabling the desulfurized solid fuel to enter an oxygen-rich fuel reactor (3), and enabling the generated sulfur-containing gas to enter an oxygen-poor fuel reactor (8) independently or after being mixed with a fluidizing medium;

chemical looping combustion stage: after the desulfurized solid fuel and the fluidized medium entering the oxygen-enriched fuel reactor (3) carry out vaporization reaction, the desulfurized solid fuel and the oxygen carrier carry out reduction reaction in the oxygen-enriched fuel reactor (3); part of unreacted and reacted oxygen carriers enter an oxygen-deficient fuel reactor (8) through a regulating valve (7), and the oxygen peroxide coefficient R in the oxygen-deficient fuel reactor (8) is controlled by controlling the entering amount of the oxygen carriers entering the oxygen-deficient fuel reactor (8); the rest oxygen carrier is input into an air reactor (13); high purity CO is separated by a first cyclone (18)₂Separating from the oxygen-fuel reactor (3);

a sulfur-containing gas fixing stage: in the oxygen-deficient fuel reactor (8), the fluidizing medium carries the incoming sulfur-containing gas and unreacted oxygen carrier to form metal sulfides, and the metal sulfides and the remaining oxygen carrier enter the air reactor (13); separating the high temperature fluidizing medium from the oxygen-depleted fuel reactor (8) by means of a second cyclone (15);

lattice oxygen recovery and sulfur release stages: in the air reactor (13), the oxygen carrier which is oxygen-deprived is restored to the oxygen carrier containing lattice oxygen by reacting with air; the metal sulfide reacts with air to generate an oxygen carrier and sulfur-containing gas; the oxygen carrier generated in the air reactor (13) is input into the oxygen fuel reactor (3), and the sulfur-containing gas generated in the air reactor (13) is separated by an AR cyclone separator (22).

2. The microwave-coupled chemical looping combustion directional desulfurization process according to the claim 1, characterized in that the microwave reactor (1) operates at a microwave frequency of 1GHz and an irradiation time of 30 s.

3. The microwave-coupled chemical looping combustion directional desulfurization process according to claim 1, characterized in that the temperature of the oxygen-rich fuel reactor (3) is 800-1200 ℃, and the oxygen peroxide coefficient R of the oxygen-rich fuel reactor (3) is 1.9-2.0.

4. The microwave-coupled chemical looping combustion directional desulfurization process according to the claim 1, characterized in that the temperature of the oxygen-deficient fuel reactor (8) is 700-1000 ℃; the opening degree of the regulating valve (7) is controlled by monitoring the concentration of sulfur-containing gas in the fluidizing medium entering the oxygen-deficient fuel reactor (8), so that the peroxide coefficient R in the oxygen-deficient fuel reactor (8) is controlled to be 0.8-0.9.

5. The microwave-coupled chemical looping combustion directional desulfurization process according to the claim 1, characterized in that the temperature inside the air reactor (13) is 800-.

6. An apparatus for a microwave technology-coupled chemical looping combustion directional desulfurization process according to claim 1, characterized by comprising a microwave reactor (1), an air reactor (13), a sufficient oxygen fuel reactor (3) and an oxygen-deficient fuel reactor (8); the microwave reactor (1) is communicated with the oxyfuel reactor (3) through a desulfurization fuel conveying pipeline (2); the bottom of the oxygen-rich fuel reactor (3) is communicated with an oxygen-poor fuel reactor (8) through a fuel reactor connecting pipeline (5), and an adjusting valve (7) is arranged on the fuel reactor connecting pipeline (5) and used for adjusting the peroxide coefficient R in the oxygen-poor fuel reactor (8); the bottom of the oxygen fuel reactor (3) is provided with a fluidized medium inlet D; the bottom of the oxygen-fuel-sufficient reactor (3) is communicated with an air reactor (13) through a first return pipe (6); the bottom of the oxygen-deficient fuel reactor (8) is communicated with an air reactor (13) through a second feed back pipe (12); the bottom of the oxygen-deficient fuel reactor (8) is provided with a mixed fluidized medium inlet F; the mixed fluidized medium inlet F is provided with a first flue gas analyzer (10) for monitoring the gas concentration at the inlet of the oxygen-deficient fuel reactor (8), the air reactor (13) is communicated with an AR cyclone separator (22) through an air reactor riser (19), and the AR cyclone separator (22) is communicated with the oxygen-deficient fuel reactor (3) through an AR cyclone separator dipleg (21).

7. The microwave-coupled device for the chemical looping combustion directional desulfurization process according to the claim 6, characterized in that the air reactor (13), the oxygen-rich fuel reactor (3) and the oxygen-poor fuel reactor (8) are provided with air distribution plates at the lower part of the reactors.

8. The device for the microwave-coupled chemical looping combustion directional desulfurization process according to the claim 6, characterized in that the first cyclone separator (18) is installed on the upper portion of the oxygen-fuel reactor (3), and the high-purity CO is arranged on the first cyclone separator (18)₂Outlet E, the high purity CO₂A third flue gas analyzer (20) is arranged at the outlet E and is used for monitoring the concentration of sulfur-containing gas at the outlet of the sufficient oxygen reactor (3), the first cyclone separator (18) is communicated with the sufficient oxygen fuel reactor (3) through a first cyclone separator dipleg (17) and is used for returning part of unreacted solid fuel and oxygen carrier to the sufficient oxygen fuel reactor (3);

the device is characterized in that a second cyclone separator (15) is arranged at the upper part of the oxygen-deficient fuel reactor (8), a high-temperature fluidized medium outlet H is formed in the second cyclone separator (15), a second flue gas analyzer (16) is arranged at the high-temperature fluidized medium outlet H and used for monitoring the concentration of sulfur-containing gas at the outlet of the oxygen-deficient fuel reactor (8), and the second cyclone separator (15) is communicated with the oxygen-deficient fuel reactor (8) through a second cyclone separator dipleg (14) and used for enabling separated solid particles to return to the oxygen-deficient fuel reactor (3).

Technical Field

The invention relates to the field of metallurgy, the field of coal combustion desulfurization or the field of environmental treatment, in particular to a chemical-looping combustion directional desulfurization process and a device coupled with a microwave technology.

Background

With rapid development of economy and continuous progress of society, energy consumption mainly based on fossil energy is increasing. However, the traditional fossil energy causes serious damage to the environment in the processes of production, transportation and utilization, and the main combustion product of the traditional fossil energy is CO₂、SO_x、NO_xAnd the like are the main points of the current environmental problems such as greenhouse effect, acid rain and the like. The traditional Combustion process is divided into two steps by the Chemical Looping Combustion (CLC) technology with the help of an Oxygen Carrier (OC), the fuel is oxidized by lattice Oxygen in the OC, and the direct contact between the fuel and air is avoided, so that the thermal type and the rapid NO are effectively inhibited_xGenerating; in addition, CO is formed at the outlet of the fuel reactor₂Is not covered by N₂Dilution without a separation device, thereby avoiding CO₂The energy-intensive process required for the separation. It can be seen that the CLC technique is a CO-bearing technique₂The clean and high-efficiency combustion technology of internal separation.

Although CLC technology can effectively inhibit NO_xCan also be used for CO₂Trapping but unavoidable SO_xGeneration and discharge of the catalyst. Influenced by geographical distribution and deposition environment, the variation range of the sulfur content in coal in China is large, and is about 0.02-10.48%. The reserve of coal with sulfur content > 2.00% accounts for 9.90% of the reserve of the whole country. The medium-high sulfur coal and even high-sulfur coal are effectively utilized, and the energy demand pressure of China can be relieved to a certain extent.

During CLC of coal, sulfur in the coal will beHas certain influence on the reaction process. This is mainly reflected in: in a fuel reactor, sulfur may react with an oxygen carrier to form a sulfur-containing compound, thereby affecting the reactivity and stability of the oxygen carrier, and a gas phase sulfur-containing substance (such as H)₂S、SO_xCOS, etc.) will also contribute to the CO at the reactor outlet₂The purity is influenced, in particular, when CO₂Middle sulfur gas (H)₂S、SO_x) The concentration of (A) is higher than 50ppm, S can be deposited on the surface of the earth and the pipeline for transportation can be corroded, and the CO can be further influenced₂Transportation and sealing utilization of the oil-water separator; in the air reactor, the sulfur-containing compounds formed in the oxygen carrier may further react with O in the air₂React to form SO_xThereby causing environmental damage.

Through the previous research on the migration and conversion rule of sulfur in coal in the CLC process, the majority of sulfur in coal is expressed as SO at the outlet of a fuel reactor₂And H₂S is escaped, and a small amount of sulfur is taken as SO at the outlet of the air reactor₂The form of (a) escapes. Although a portion of the sulfur compounds can be removed by means of the added desulfurizing agent, the concentration of the sulfur compounds in the gas phase at the outlet of the fuel reactor may still exceed 100ppm, thereby seriously affecting CO₂And its subsequent capture and sequestration process, how to reduce CO in the fuel reactor₂The concentration of sulfur-containing gas in (1) is a problem to be solved urgently.

Disclosure of Invention

Aiming at the defects in the prior art, the invention provides a chemical looping combustion directional desulfurization process and a device thereof coupled with a microwave technology. On one hand, the desulfurization from the source is realized, so that the CO generated in the fuel reactor₂After being trapped, the catalyst meets the utilization and sealing conditions without further desulfurization; on the other hand, the S element is directionally moved through the circulation of the oxygen carrierMove to air reactor and release for the gas that contains sulfur, can utilize traditional desulphurization unit to the desorption of the pollutant that contains sulfur, reduce the running cost, promote the reliability.

The present invention achieves the above-described object by the following technical means.

A microwave technology-coupled chemical-looping combustion directional desulfurization process comprises the following steps:

and (3) microwave desulfurization: mixing solid fuel with H₂Adding the solid fuel into a microwave reactor, carrying out desulfurization reaction on the solid fuel through microwave frequency, enabling the desulfurized solid fuel to enter an oxygen-rich fuel reactor, and enabling the generated sulfur-containing gas to enter the oxygen-poor fuel reactor independently or after being mixed with a fluidized medium;

chemical looping combustion stage: after the desulfurized solid fuel and the fluidized medium entering the oxygen-enriched fuel reactor carry out vaporization reaction, the desulfurized solid fuel and the oxygen carrier carry out reduction reaction in the oxygen-enriched fuel reactor; part of unreacted and reacted oxygen carriers enter the oxygen-deficient fuel reactor through a regulating valve, and the oxygen peroxide coefficient R in the oxygen-deficient fuel reactor is controlled by controlling the entering amount of the oxygen carriers entering the oxygen-deficient fuel reactor; inputting the residual oxygen carrier into an air reactor; passing high purity CO through a first cyclone₂Separating from the oxygen-fuel reactor;

a sulfur-containing gas fixing stage: in the oxygen-deficient fuel reactor, the sulfur-containing gas carried by the fluidizing medium and unreacted oxygen carrier generate metal sulfide, the fluidizing medium simultaneously plays a fluidizing role, and the metal sulfide and the residual oxygen carrier enter the air reactor; separating the high temperature fluidizing medium from the oxygen-depleted fuel reactor by a second cyclone;

lattice oxygen recovery and sulfur release stages: in the air reactor, the oxygen carrier which is subjected to reaction reacts with air, so that the oxygen carrier which is subjected to oxygen loss is recovered to an oxygen carrier containing lattice oxygen; the metal sulfide reacts with air to generate an oxygen carrier and sulfur-containing gas; and oxygen carriers generated in the air reactor are input into the oxygen-fuel full reactor, and sulfur-containing gas generated in the air reactor is separated by the AR cyclone separator.

Further, the microwave frequency of the microwave reactor is 1GHz, and the radiation time is 30 s.

Further, the temperature of the oxygen-rich fuel reactor is 800-1200 ℃, and the oxygen peroxide coefficient R of the oxygen-rich fuel reactor is 1.9-2.0.

Further, the temperature of the oxygen-deficient fuel reactor is 700-1000 ℃; the concentration of the sulfur-containing gas at the inlet of the oxygen-deficient fuel reactor is monitored, and the opening of the regulating valve is controlled, so that the oxygen peroxide coefficient R in the oxygen-deficient fuel reactor is controlled to be 0.8-0.9.

Further, the temperature inside the air reactor was 800-.

A device for a chemical looping combustion directional desulfurization process coupled with a microwave technology comprises a microwave reactor, an air reactor, a sufficient oxygen fuel reactor and an oxygen-deficient fuel reactor; the microwave reactor is communicated with the oxyfuel reactor through a desulfurization fuel conveying pipeline; the bottom of the oxygen-rich fuel reactor is communicated with the oxygen-poor fuel reactor through a fuel reactor connecting pipeline, and an adjusting valve with a powder flowmeter is arranged on the fuel reactor connecting pipeline and is used for adjusting the peroxide coefficient R in the oxygen-poor fuel reactor; the bottom of the sufficient oxygen fuel reactor is provided with a fluidized medium inlet D; the bottom of the oxygen-fuel-sufficient reactor is communicated with the air reactor through a first return pipe; the bottom of the oxygen-deficient fuel reactor is communicated with the air reactor through a second return pipe; the bottom of the oxygen-deficient fuel reactor is provided with a mixed fluidized medium inlet F; the air reactor is communicated with the AR cyclone separator through an air reactor riser, and the AR cyclone separator is communicated with the sufficient oxygen fuel reactor through an AR cyclone separator dipleg.

Furthermore, the lower parts of the air reactor, the sufficient oxygen fuel reactor and the oxygen-deficient fuel reactor are provided with air distribution plates.

Further, a first cyclone separator is arranged at the upper part of the oxygen-enriched fuel reactor, and high-purity CO is arranged on the first cyclone separator₂An outlet E, the first cyclone being in communication with the oxyfuel reactor via a first cyclone dipleg for passing part of the unreacted solid fuel and oxygen carrierReturning the body to the oxygen-fuel reactor;

and the upper part of the oxygen-deficient fuel reactor is provided with a second cyclone separator, the second cyclone separator is provided with a high-temperature fluidized medium outlet H, and the second cyclone separator is communicated with the oxygen-deficient fuel reactor through a dipleg of the second cyclone separator and is used for returning the separated solid particles to the oxygen-deficient fuel reactor.

The invention has the beneficial effects that:

1. the microwave-coupled chemical-looping combustion directional desulfurization process provided by the invention has the advantages that about 70% of S in the solid fuel is in a gaseous H state under specific conditions by adding the microwave reactor₂S form separation, which obviously reduces the concentration of sulfur-containing gas at the outlet of the oxy-fuel reactor and effectively ensures CO₂And the subsequent transportation and storage processes are effectively carried out, and the use of desulfurizing agents (limestone, micaceous stone, etc.) in the fuel reactor is reduced.

2. The invention relates to a microwave technology-coupled chemical looping combustion directional desulfurization process, wherein a first flue gas analyzer and a second flue gas analyzer are respectively arranged at an inlet and an outlet of an oxygen-poor fuel reactor and used for monitoring the concentration of gas in real time, the first flue gas analyzer is associated with an adjusting valve, the adjusting valve is changed when the concentration is changed, and the opening degree of the adjusting valve is also increased when the concentration of sulfur-containing gas is increased, so that the circulation amount of an oxygen carrier in the oxygen-poor fuel reactor is controlled, the lower peroxide coefficient R in the oxygen-poor fuel reactor is ensured, and the oxygen carrier is easier to react with the sulfur-containing gas (H) under the condition₂S、COS、CS₂Etc.) to generate metal sulfide, and the metal sulfide is directionally transferred into an air reactor through a return pipe, and S in the metal sulfide is oxidized into SO in the air reactor₂The effect of directional desulfurization can be achieved only by installing a set of traditional desulfurization device at the tail of the air reactor.

3. The oxygen carrier is used for chemical looping combustion oxygen supply in an oxygen-rich fuel reactor on one hand, and reacts with S-containing gas in an oxygen-poor fuel reactor on the other hand, so that the purpose of fixing S element is achieved, and the fixation of the S element is facilitatedReleasing S element after transferring to air reactor to reduce CO trapped by S-containing gas pair₂The desulfurization device is fully utilized to remove the S element under the influence of the purity of the sulfur-containing compound.

4. The invention relates to a chemical looping combustion directional desulfurization process coupled with microwave technology, wherein a microwave reactor is used for removing part S in coal; the oxygen-rich fuel reactor receives the coal with part of S removed, burns and releases heat to obtain low-sulfur CO₂A gas; the oxygen-deficient fuel reactor receives S-containing gas precipitated by the microwave reactor, and the S-containing gas reacts with the oxygen carrier to generate metal sulfide and fix the S element; supplying oxygen to the air reactor, restoring lattice oxygen for oxygen carrier, and reacting with metal sulfide to generate SO₂Introducing SO₂And releasing and desulfurizing by using a tail desulfurizing device. Through the mutual matching of the main components, the S element is converted from a gaseous state into a solid state and is directionally transferred to the air reactor and then is converted back into the gaseous state, so that the subsequent removal work is facilitated.

Drawings

FIG. 1 is a schematic diagram of a chemical looping combustion directional desulfurization device coupled with microwave technology according to the present invention.

FIG. 2a is a sulfur-containing gas concentration distribution diagram of an outlet of a sufficient reactor of a copper-based oxygen carrier in different peroxide coefficients R scheme in the prior art.

FIG. 2b is a sulfur-containing gas concentration distribution diagram of the outlet of the sufficient reactor under different peroxide coefficients R scheme of the copper-based oxygen carrier.

FIG. 3a is a concentration distribution diagram of sulfur-containing gas at the outlet of a sufficient reactor under different peroxide coefficients R schemes of a nickel-based oxygen carrier in the prior art.

FIG. 3b is a sulfur-containing gas concentration distribution diagram of the outlet of the foot reactor under different peroxide coefficients R schemes of the nickel-based oxygen carrier.

FIG. 4 is a flow chart of the chemical looping combustion directional desulfurization process of the coupled microwave technology of the present invention.

FIG. 5 is a graph showing the distribution of products of oxygen-deficient fuel reactors with copper-based oxygen carriers under different peroxide coefficients R.

In the figure:

1-a microwave reactor; 2-a desulfurized fuel delivery conduit; 3-foot oxygen combustionA material reactor; 4-a first air distribution plate; 5-fuel reactor connecting line; 6-a first return pipe; 7-adjusting valve; 8-an oxygen-deficient fuel reactor; 9-a second air distribution plate; 10-a first flue gas analyzer; 11-AR air distribution plate; 12-a second return pipe; 13-an air reactor; 14-a second cyclone dipleg; 15-a second cyclone separator; 16-a second flue gas analyzer; 17-a first cyclone dipleg; 18-a first cyclone separator; 19-an air reactor riser; 20-a third flue gas analyzer; 21-AR cyclone dipleg; 22-AR cyclone separator; a-a solid fuel feed port; B-H₂An air inlet; c-a sulfur-containing gas outlet; d-a fluidizing medium inlet; e-high purity CO₂An outlet; f-a mixed fluidizing medium inlet; g-an oxygen carrier inlet; an H-high temperature fluidizing medium outlet; i, a slag discharge port; j-air inlet; k-hot flue gas outlet containing sulfur and oxygen.

Detailed Description

The invention will be further described with reference to the following figures and specific examples, but the scope of the invention is not limited thereto.

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are illustrative and intended to be illustrative of the invention and are not to be construed as limiting the invention.

In the description of the present invention, it is to be understood that the terms "central," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "axial," "radial," "vertical," "horizontal," "inner," "outer," and the like are used in the orientations and positional relationships indicated in the drawings for convenience in describing the present invention and for simplicity in description, and are not intended to indicate or imply that the referenced devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and are not to be considered limiting. Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless specifically defined otherwise.

In the present invention, unless otherwise expressly specified or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can, for example, be fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

As shown in FIG. 1, the apparatus for chemical looping combustion directional desulfurization coupled with microwave technology according to the present invention comprises a microwave reactor 1, an air reactor 13, a sufficient oxygen fuel reactor 3 and an oxygen-deficient fuel reactor 8; the microwave reactor 1 is respectively provided with a solid fuel feed port A, H₂A gas inlet B and a sulfur-containing gas outlet C; the microwave reactor 1 is communicated with the sufficient oxygen fuel reactor 3 through a desulfurization fuel conveying pipeline 2; a first air distribution plate 4 is arranged in the sufficient oxygen fuel reactor 3, a fluidized medium inlet D is arranged at the bottom of the sufficient oxygen fuel reactor 3, a first cyclone separator 18 is arranged at the upper part of the sufficient oxygen fuel reactor 3, and high-purity CO is arranged on the first cyclone separator 18₂Outlet E, the high purity CO₂A third flue gas analyzer 20 is arranged at the outlet E, and the first cyclone separator 18 is communicated with the oxygen-rich fuel reactor 3 through a first cyclone separator dipleg 17 and is used for returning part of unreacted solid fuel and oxygen carrier to the oxygen-rich fuel reactor 3; the bottom of the oxygen-rich fuel reactor 3 is communicated with an oxygen-poor fuel reactor 8 through a fuel reactor connecting pipeline 5, and the fuel reactor connecting pipeline 5 is provided with an adjusting valve 7 for adjusting the peroxide coefficient R in the oxygen-poor fuel reactor 8; the bottom of the oxygen-fuel-sufficient reactor 3 is communicated with an air reactor 13 through a first return pipe 6; the oxygen-deficient fuelA second air distribution plate 9 is arranged in the reactor 8, a mixed fluidized medium inlet F is arranged at the bottom of the oxyfuel reactor 3, mixed gas of a fluidized medium and sulfur-containing gas enters the mixed fluidized medium inlet F, and a first flue gas analyzer 10 is arranged at the mixed inlet F and used for detecting the sulfur concentration in the fluidized medium and the sulfur-containing gas; the upper part of the oxygen-fuel-sufficient reactor 3 is also provided with an oxygen carrier inlet G for supplementing an oxygen carrier. A second cyclone separator 15 is arranged at the upper part of the oxygen-deficient fuel reactor 8, a high-temperature fluidized medium outlet H is arranged on the second cyclone separator 15, and a second flue gas analyzer 16 is arranged at the high-temperature fluidized medium outlet H and used for monitoring the concentration of sulfur-containing gas at the outlet of the oxygen-deficient fuel reactor 8; the second cyclone 15 communicates with the oxygen-depleted fuel reactor 8 via a second cyclone dipleg 14 for returning the separated solid particles to the oxygen-depleted fuel reactor 3. The bottom of the oxygen-deficient fuel reactor 8 is communicated with an air reactor 13 through a second return pipe 12; a slag discharge port I is formed at the bottom of the oxygen-deficient fuel reactor 8; the air reactor 13 is internally provided with an AR air distribution plate 11, the bottom of the air reactor 13 is provided with an air inlet J, the air reactor 13 is communicated with an AR cyclone separator 22 through an air reactor lifting pipe 19, and the AR cyclone separator 19 is communicated with the sufficient oxygen fuel reactor 3 through an AR cyclone separator dipleg 21. And a sulfur-containing oxygen-poor hot flue gas outlet K is arranged on the AR cyclone separator 21.

Example 1

Oxygen carrier for chemical-looping combustion is selectively synthesized into oxygen carrier, and copper-based oxygen carrier is used for preparing CuO/SiO by adopting an immersion method₂In which CuO/SiO₂In a mass ratio of 50: 50. the solid fuel is Xinzhou coal, the fluidizing medium is selected from steam and CO₂The mixed gas of (1). Table 1 is the industrial and elemental analysis of Xinzhou coal.

TABLE 1 Inzhou coal Industrial and elemental analysis

The coal has high content of inorganic sulfur, and sulfate sulfur in the coal is not easy to decompose at high temperature, especially calcium sulfate. So about 10% of the sulfur in coal exists in the form of sulfate sulfur and does not participate in the reaction.

For the chemical looping dual circulating fluidized bed of the prior art:

firstly, the related functions of the microwave heater 1 are closed, the regulating valve 7 and the second material return pipe 12 are closed, the other components are utilized to simulate the traditional chemical-looping double-circulation fluidized bed, a new oxygen carrier, a desulfurizer and solid fuel enter the reactor from a solid fuel inlet A, the temperature in the sufficient oxygen fuel reactor 3 is set to be 800-₂Collecting SO₂The concentration of S in the gas is 195.24ppm, higher than CO, as shown in FIG. 2a₂The required concentration for the subsequent capture and sequestration process. Changing the peroxide coefficient R in the fuel reactor, leaving the remaining conditions unchanged, and monitoring the tail CO₂Collecting SO₂As shown in FIG. 2a, the S concentration was out of limits. Wherein the main reactions taking place in the fuel reactor are as follows:

2.153C_58.6833H_31.75S_0.91875(H₂O)_6.2361(N₂)_0.9287+291.658CuO＝

291.658Cu+126.757CO₂+47.615H₂O+1.978SO₂+1.464N₂

while the remaining conditions were unchanged even though the peroxide coefficient R in the oxy-fuel reactor was changed, the tail CO was monitored₂Collecting SO₂As shown in FIG. 2a, the S concentration was out of limits.

The chemical looping combustion directional desulfurization process of the coupling microwave technology comprises the following steps:

and (3) microwave desulfurization: in the microwave reactor 1, H₂From H₂The coal is added from a solid fuel feed inlet A, the microwave frequency is 1GHz, the radiation time is 30S, and S elements and H in the coal₂Reaction to form H₂S, the desulfurized coal enters an oxygen-rich fuel reactor 3 through a desulfurized fuel conveying pipeline 2, and the pulverized coal is pyrolyzed by a microwave reactor and then contains sulfurGas (H)₂、CO、CO₂、H₂O、N₂And H₂S) is escaped into a lean oxygen reactor, and H in the synthesis gas₂、CO、CO₂、H₂O and N₂The ratio of each is 45%, 32%, 10% and 3%. The sulfur-containing synthetic gas accounts for 40 percent of the total mass of the coal powder, and H₂S is very small in the synthesis gas, but H₂S accounts for 70% of total sulfur. The sulfur-containing synthesis gas is transported to mix with the fluidizing medium and then introduced into the bottom of the oxygen-depleted fuel reactor 8 through the fluidizing medium and sulfur-containing gas mixing inlet F.

Coal chemical looping combustion stage: in the sufficient oxygen fuel reactor 3, the sufficient oxygen fuel reactor 3 is a bubbling bed, the temperature is set to 800-. A first cyclone separator 18 is provided in the upper part of the oxy-fuel reactor 3, and the generated gas is separated from high purity CO₂An outlet E is separated, and high-purity CO is obtained after condensation and dehydration₂. Part of the unreacted solid fuel and the reacted and unreacted oxygen carrier are returned from the first cyclone dipleg 17 to the oxyfuel reactor 3 to continue to participate in the reaction. After the reaction is finished, the oxygen carrier is transferred from the upper oxygen-rich fuel reactor 3 to the lower oxygen-poor fuel reactor 8 through the fuel reactor connecting pipeline 5, the regulating valve 7 is arranged on the fuel reactor connecting pipeline 5, the circulation quantity of the oxygen carrier in the oxygen-poor fuel reactor 8 is controlled through the regulating valve 7, so that the oxygen-poor fuel reactor 8 is ensured to have a lower peroxide coefficient R, the redundant oxygen carrier directly returns to the air reactor 13 through the first return pipe 6 on one side of the fuel reactor connecting pipeline 5, and the main reaction in the oxygen-rich fuel reactor 3 is as follows:

5.442C_35.21H_19.05S_0.18375(H₂O)_3.741(N₂)_0.557+437.075CuO＝

437.075Cu+191.619CO₂+72.196H₂O+SO₂+1.516N₂

a sulfur-containing gas fixing stage: in the oxygen-poor fuel reactor 8, the oxygen-poor fuel reactor 8 is a bubbling bed, the temperature is set to be 700- The product distribution at different peroxide coefficients R is shown in FIG. 5. H in sulfur-containing gases at the current peroxide coefficients R of 0.8-0.9₂The S gas and the unreacted oxygen carrier are easy to react to generate copper sulfide (generally Cu)₂S, CuS) sulfur-containing gas and fluidizing gas (CO)₂) Introducing the mixture of the fluidized medium and the sulfur-containing gas into the bottom of the oxygen-deficient fuel reactor 8 from a mixing inlet F, adding a new oxygen carrier from an oxygen carrier inlet G, and then reacting with the sulfur-containing gas carried in by the fluidized medium to obtain copper sulfide (Cu)₂S, CuS) and reacted and unreacted oxygen carriers are returned from the second return line 12 to the air reactor 13. The oxygen-deficient fuel reactor 8 is provided with a second cyclone separator 15 at the upper part, the separated solid particles are returned to the oxygen-deficient fuel reactor 8 from the lower dipleg 14 to participate in the reaction continuously, the high-temperature fluidizing medium exits from a high-temperature fluidizing medium outlet H, the high-temperature fluidizing medium is basically free of gaseous S, and the gas is treated and then is introduced into the oxygen-deficient fuel reactor 8 again from F. Solid residues are discharged from a slag discharge port I at the bottom. The main reactions taking place in the oxygen-depleted fuel reactor 8 are as follows: (sulfur-containing gas andH₂s example)

2CuO+H₂S(g)+H₂(g)＝Cu₂S+2H₂O(g)

H₂S(g)+CuO＝CuS+H₂O(g)

And (3) recovering lattice oxygen to release sulfur: in the air reactor 13, the temperature inside the air reactor 13 was set to 800-,

the copper sulphide and oxygen carrier react with air J introduced from the bottom of the air reactor 13, on the one hand, oxygen lost oxygen carrier reverts lattice oxygen, on the other hand, oxidation reaction with copper sulphide occurs, SO that the copper sulphide is recovered as oxygen carrier and releases sulphur-containing gas, mainly SO₂. After passing through a riser 19 of the air reactor, the gas is separated by an AR cyclone separator 22 at the upper part, the gas with poor oxygen and sulfur leaves through a sulfur-containing and poor oxygen hot flue gas outlet K and is then desulfurized by a conventional desulfurization device, and the obtained solid oxygen carrier particles are sent to an oxygen-enriched fuel reactor 3 through a dipleg 21 of the AR cyclone separator to react with solid fuel. Completing one cycle. The main reactions taking place in the air reactor 13 are as follows:

2Cu+O₂(g)＝2CuO

Cu₂S+2O₂(g)＝2CuO+SO₂(g)

2CuS+3O₂(g)＝2CuO+2SO₂(g)

monitoring the device tail CO with a third flue gas analyzer 20₂Collecting SO₂The concentration of sulfur in the gas collected here is 49.10ppm, lower than the desired 50ppm, as shown in FIG. 2 b. Changing the peroxide coefficient R in the oxy-fuel reactor, leaving the remaining conditions unchanged, and monitoring the tail CO₂Collecting SO₂The concentration of (3) is as shown in FIG. 2b, and the S concentration is satisfactory.

Example 2

Chemical looping double circulating fluidized bed of the prior art:

adopting a nickel-based oxygen carrier to prepare an oxygen carrier NiO/Al by an impregnation method₂O₃Wherein NiO/Al₂O₃The mass ratio of (A) to (B) is 40: 60. other conditions are unchanged, the improved device and the traditional chemical chain double circulation are monitoredFluidized bed tail CO₂Collecting SO₂As shown in fig. 3 a. When the peroxide coefficient R in a fuel reactor in a traditional chemical-looping double-circulation fluidized bed is 2.0, the main reactions occur as follows:

2.092C_58.6833H_31.75S_0.478125(H₂O)_6.2361(N₂)_0.7+280.675NiO(s)＝

280.675Ni(s)+122.736CO₂+46.245H₂O+SO₂+1.464N₂

the fuel reactor outlet sulfur gas concentration was 145.70 ppm. Changing the peroxide coefficient R in the fuel reactor, leaving the remaining conditions unchanged, and monitoring the tail CO₂Collecting SO₂As shown in FIG. 3a, the S concentration was out of limits.

The invention relates to a chemical looping combustion directional desulfurization process of a coupling microwave technology, which comprises the following steps:

adopting a nickel-based oxygen carrier to prepare an oxygen carrier NiO/Al by an impregnation method₂O₃Wherein NiO/Al₂O₃The mass ratio of (A) to (B) is 40: 60. other conditions are unchanged, and the improved device and the tail CO of the traditional chemical-looping double-circulating fluidized bed are monitored₂Collecting SO₂As shown in fig. 3 b. When the peroxide coefficient R in the oxygen-rich fuel reactor in the device is 2.0, the main reactions occur as follows:

10.458C_58.6833H_31.75S_0.095625(H₂O)_6.2361(N₂)_0.7+1395.376NiO＝

1395.376Ni+613.682CO₂+231.227H₂O+SO₂+7.32N₂

the sulfur-containing gas concentration at the outlet of the oxygen-fuel full reactor is 48.06 ppm. Changing the peroxide coefficient R in the oxy-fuel reactor, leaving the remaining conditions unchanged, and monitoring the tail CO₂Collecting SO₂The S concentrations are all satisfactory as shown in FIG. 3 b.

By combining the above embodiments, comparing the present invention with the prior art, it can be found that the reduction of S element in the tail gas can reach 67% after the process flow of the present invention is adopted, and the effect is significant.

It should be understood that although the present description has been described in terms of various embodiments, not every embodiment includes only a single embodiment, and such description is for clarity purposes only, and those skilled in the art will recognize that the embodiments described herein may be combined as suitable to form other embodiments, as will be appreciated by those skilled in the art.

The above-listed detailed description is only a specific description of a possible embodiment of the present invention, and they are not intended to limit the scope of the present invention, and equivalent embodiments or modifications made without departing from the technical spirit of the present invention should be included in the scope of the present invention.