CN105771809A - Semi-continuous microwave catalytic thermal cracking reactor - Google Patents

Abstract

The invention discloses a semi-continuous microwave catalytic pyrolysis reactor, which is a vertical structure, including a heating chamber, a microwave heating source and a catalytic fixed bed device; The material reacts in the quartz reaction chamber; there are two sets of umbrella-shaped partitions in the reaction chamber, and the upper umbrella in each group is smaller than the lower umbrella, so that the material can slide from top to bottom, so that Increase the movement distance of materials; the umbrella partition can be rotated as needed. There are three groups of microwave heating sources extending to the heating chamber, and the axes of each group of microwave heating sources are not coincident to reduce mutual interference. A catalytic fixed bed device can be installed in the reactor, and the reactor is also provided with two temperature measuring ports, one of which can be used according to the needs. The invention can increase the conversion rate of biomass, improve heating stability, has the advantage of integrating heating and catalysis, and can be applied to the fields of energy, chemical industry and the like.

Description

A semi-continuous microwave catalytic pyrolysis reactor

technical field

The invention belongs to the technical field of microwave reactors, and relates to a microwave catalytic pyrolysis technology, which improves the conversion rate and product selectivity of biomass reactions.

technical background

With the utilization and development of biomass, microwave pyrolysis technology has developed into a new type of pyrolysis technology in recent years. The microwave heating rate is fast, the energy consumption is small, and it is easy to control. The particles in the material vibrate under the action of microwaves, which causes violent friction between the material particles and converts electromagnetic energy into heat energy. Microwave thermal cracking technology is to heat the raw material to 300-650°C by microwave under the condition of no oxygen, crack it into low-molecular organic vapor in a short time, and obtain liquid product after rapid cooling. Compared with the traditional pyrolysis method, the microwave pyrolysis method has certain advantages: (1) Microwave can quickly and evenly heat the inside and outside of the material, shorten the heating time, and does not require raw material pretreatment steps (such as drying, reducing particle size), Reduce production costs and energy consumption; (2) The reaction conditions are milder, and the heat loss in the heat conduction process is less, thereby promoting the chemical reaction of raw materials and improving the quality of the obtained products. The existing microwave reactor generally adopts the method of discontinuous feeding, and the material is added at one time, so that the material accumulates in the reactor, and there is uneven heating and local high temperature, which affects the conversion rate of the raw material; in the microwave where the raw material and the catalyst are directly mixed In the process of pyrolysis reaction, there are problems such as easy deactivation of catalyst, large amount of catalyst used, and affecting the conversion rate of raw materials. The catalytic device of the general catalytic pyrolysis reactor is used in series with the pyrolysis reactor, and the catalytic fixed bed needs to be heated separately. The present invention adopts the pyrolysis-catalytic upgrading method in combination of a microwave pyrolysis device and a fixed bed catalytic reactor, installs the catalytic fixed bed directly in the microwave pyrolysis reactor, and uses microwaves to heat it at the same time, thereby improving the conversion of raw materials. While improving the efficiency and working efficiency, the selectivity of pyrolysis products is improved and the cost is reduced.

Contents of the invention

The purpose of the present invention is to provide a kind of semi-continuous microwave catalytic pyrolysis reactor, to improve the problem of its material accumulation, stability when heating and improve conversion rate, and catalyzing fixed bed unit is integrated wherein, to improve the obtained Product selectivity, lower production costs.

In order to solve the above problems, the concrete technical scheme that the present invention adopts is as follows:

A semi-continuous microwave catalytic pyrolysis reactor, including a heating chamber and a plurality of microwave heating sources extending to the heating chamber, the heating chamber is provided with a temperature detection port, a feed port, a feed port, a gas inlet and a gas outlet, and a heating chamber. The outside of the chamber is connected with the control system, and the feature is that: the heating chamber has a hexagonal structure, and the microwave heating source is distributed on the three surfaces of the heating chamber edge in steps; the feed inlet is equipped with a feed adjustment device; There is a quartz reaction cavity inside the heating chamber, which can make the microwave pass through, and the material reacts in the quartz reaction cavity;

A catalytic device and two sets of umbrella-shaped baffles are installed in the quartz reaction chamber; the umbrella-shaped baffles are composed of two sets of umbrella-shaped structures, and are placed according to the front and back positions; the lower umbrella-shaped structure is larger than the upper one. Large, the upper umbrella is upright, and the lower umbrella is placed upside down; there is a round hole in the middle of the lower umbrella structure, which is used for material drop; the outer surface of the umbrella-shaped partition is coated with a layer of silicon carbide, which is Silicon has a wave-absorbing effect to increase the stability of the reaction and increase the heating rate of the reaction;

The middle of the two groups of umbrella-shaped structures is connected by a main strut, the upper upright umbrella-shaped structure is directly fixed on the main strut, and the lower inverted umbrella-shaped structure is connected to the main strut through a strut; the umbrella-shaped partition The rotation is carried out by the main support rod; the rotation is controllable and can be selected according to needs, so as to not only increase the moving distance of the material, but also increase the heating rate.

The structure of the heating chamber is a regular hexagon in cross section, three groups of microwave heating sources are distributed on the edge of the heating chamber, a total of 9, and the axes of each heating source in each group are not coincident, and every other outer surface of the heating chamber is installed Three microwave heating sources.

The microwave heating sources are installed on the outer edge of the heating chamber and extend to the heating chamber. Each heating source is distributed on the outer edge of the heating chamber in a step shape on different levels to reduce mutual interference between the heating sources.

The inside of the catalytic device can be filled with a catalyst to catalytically upgrade the gas produced by the pyrolysis reaction, and the outlet of the catalytic device is connected to the gas outlet of the heating chamber.

There is a temperature measuring point on the top and bottom of the heating chamber, and the temperature measuring point adopts a non-contact infrared temperature sensor, and the temperature measuring point can be flexibly selected for temperature measurement according to the needs.

The invention has beneficial effects . In the present invention, the combination of microwave reaction and catalytic fixed bed reduces the heating source, reduces the cost, and makes full use of the microwave source; the present invention uses the technical scheme of the umbrella-shaped partition to increase the movement distance of the material and solve the problem of material accumulation, thereby Make the reaction sufficient and improve the conversion rate of raw materials; the present invention stabilizes the reaction temperature and increases the heating rate by adopting the technical scheme of absorbing materials such as silicon carbide partitions; the present invention makes the measurement The temperature is flexible and adjustable, more accurate.

Description of drawings

Fig. 1 is the overall structural representation of the present invention;

Fig. 2 is a top view schematic diagram of the heating chamber of the present invention;

Fig. 3 is a schematic cross-sectional view of a heating chamber of the present invention;

Fig. 4 is a schematic diagram of a microwave heating source outside the heating chamber of the present invention;

Fig. 5 is a schematic diagram of an umbrella-shaped partition in the inner cavity of the present invention;

Figure 6 is an enlarged schematic view of a strut of the present invention;

In the figure: 1—gas outlet, 2—feed inlet, 3—feed adjustment device, 4—temperature measuring port, 5—gas inlet, 6—microwave heating source, 7—heating chamber, 8—feed outlet, 9 -control panel.

detailed description

The technical solution of the present invention will be described in further detail below in conjunction with the accompanying drawings.

Example 1

A semi-continuous microwave catalytic pyrolysis reactor as shown in Figure 1 includes a heating chamber 7 and a microwave heating source 6; wherein the heating chamber 7 is provided with a gas inlet 5, a gas outlet 1, a feed port 2, and a discharge Port 8 and two temperature measuring ports 4; the feed port 2 is equipped with a feed regulating device 3 to control the speed of feed. The microwave heating source 6 outside the heating chamber is regulated by the control panel 9 . The axis of the heating chamber 7 extends in the vertical direction, and a plurality of groups of microwave heating sources 6 are arranged outside it, and each group is composed of three microwave heating sources, and are on the same vertical axis.

The schematic diagram of the top view of the heating chamber as shown in Figure 2, the heating chamber 7 is a regular hexagonal structure; the gas inlet 5 is to feed nitrogen in the experiment to ensure that the experiment is under the condition of anaerobic or anoxic; the feed port 2 is biomass The raw material inlet end and the gas outlet 1 are connected to the catalytic fixed bed device, and the gas passes through the catalyst and comes out from the outlet 1.

As shown in Figure 3 and Figure 4, the cross-sectional view of the heating chamber 7 is a regular hexagon, and there are three groups of microwave heating sources 6 extending to the heating chamber outside. On the three faces of the hexagon, the radial axes of the three groups of microwave heating sources do not coincide;

In the structural diagram mentioned in the appeal, gas is first introduced into the vent port to generate an anoxic or anoxic environment for thermal cracking. At this time, the regulating device of the feed port is closed, and the discharge port is also in a closed state; The inner cavity in the heating chamber and the adjusting device on the feeding port can control the feeding rate; the cross-section of the heating chamber is a regular hexagon to facilitate the installation of the microwave heating source, so that the radial axes do not coincide and the mutual There is no interference between them, the effect of microwave heating is improved, and the conversion rate of the reaction is improved. Before starting to pass the gas, a catalytic device can be installed inside it, and a catalytic fixed bed reactor can be introduced into the heating chamber. The quality of the reaction product is improved, the activity of the catalyst is improved, the quality of the reaction product is improved, especially for the liquid product, the reaction time is shortened, and the conversion cost is reduced.

The three groups of microwave heating sources on the edge of the heating chamber have three heating sources in each group in the vertical direction, and each group of heating sources is not on the same horizontal plane, and all microwave heating sources are distributed in steps to reduce the distance between the heating sources. Interfere with each other to improve the heating effect. The inner wall of the heating chamber is a circular structure, which increases its internal volume. The material is reacted in the inner cavity, and the outer surface is coated with silicon carbide, which has good wave absorption effect, can promote the heat transfer of biomass pyrolysis reaction, and improve the heating rate and reaction efficiency.

Example 2

As shown in Figure 5, an umbrella-shaped partition is placed in the heating chamber, and the partition consists of two groups of umbrella-shaped structures. After the material enters the heating chamber through the feed port, it falls down through the outer surface of the umbrella structure. The diameter of the first umbrella structure is 3 to 4 cm smaller than the diameter of the heating chamber; the material falls into the second umbrella through the edge of the first umbrella. An inverted umbrella-shaped interior, the diameter of the umbrella-shaped structure is only slightly smaller than the diameter of the heating chamber; the material passes through the umbrella-shaped point a, and falls down to the second set of umbrella-shaped structures.

Figure 6 is an enlarged view at a, in which a1 is a strut that supports the inverted umbrella structure, and a2 is the main strut that supports the entire structure. The bottom of the inverted umbrella-like structure is a round hole, which is fixed on the main pole through the pole. The material can enter the next group of umbrella structures through the round hole, and the diameter of the round hole is as large as that of the feed port; considering the material blockage during the falling process, an adjustment device is installed at the feed port; when the material falls too much When it is fast, the feed port can be made smaller by rotating 3 to reduce the entry of materials, thereby preventing the blockage of materials when falling.

Through the movement of the above-mentioned materials, they will eventually accumulate at the discharge port, and the discharge port will be opened at regular intervals, so that the heated ash can be discharged through the discharge port. The device increases the moving distance of the material, makes it fall along the umbrella-shaped structure, increases its contact area, and makes the material get a good heating state, thereby improving its reaction rate. Improve the quality of reaction products, especially for liquid products, and reduce conversion costs.

The working process of the present invention is: before experiment starts, feed nitrogen at gas inlet 5 earlier, to guarantee that reaction condition is under the state of anoxic or anaerobic; The feed adjustment device 3 can adjust the flow rate of the material. The material enters the inner cavity, falls along the outer edge of the upper umbrella-shaped partition, enters the inner edge of the lower umbrella-shaped partition, and passes through the middle hole of the lower umbrella-shaped partition. Enter the second group of umbrella-shaped partitions; the umbrella-shaped partitions can be rotated, and when the material is not easy to fall, the partition can be rotated; the residue of the material after the final reaction is discharged through the discharge port 8; there are 4 temperature measuring ports during the reaction A non-contact infrared thermometer is used to measure and feed back the reaction temperature in the heating chamber. The gas generated in the reaction is discharged from the gas outlet 1 through the catalytic fixed bed, and the liquid and gas products are obtained after being condensed by the condensation system.

Claims (5)

1. a semi continuous microwave catalysis pyrolysis reactor, including adding hot cell and multiple extending to the microwave heating source adding hot cell, add hot cell and be provided with temperature detection mouth, charging aperture, discharging opening, gas feed and gas outlet, the outside adding hot cell is connected with control system, it is characterised in that: adding hot cell is hexagonal structure, and microwave heating source is by stepped three faces being distributed in the outdoor edge of heating；Equipped with feeding regulating device on described charging aperture；Heating chamber has quartz reaction inner chamber, can make microwave transparent, and material reacts in quartz reaction inner chamber；

Quartz reaction inner chamber is provided with catalytic unit and two groups of umbrella dividing plates；Described umbrella dividing plate is made up of two groups of umbrella-shaped structures, and places according to positive and negative position；The umbrella-shaped structure of lower section is bigger than the umbrella-shaped structure of top, and top umbrella is upright, and lower section umbrella is placed for standing upside down；A circular hole is had, for the decline of material in the middle of the umbrella-shaped structure of lower section；The outer surface of described umbrella dividing plate scribbles one layer of carborundum, utilizes carborundum to have the stability inhaling ripple effect increase reaction, improve reaction heating rate；

Connecting by main supporting rod in the middle of described two groups of umbrella-shaped structures, the upright umbrella-shaped structure in top is directly anchored on main supporting rod, and the umbrella-shaped structure stood upside down in lower section passes through pole and is connected with main supporting rod；Described umbrella dividing plate is rotated by main supporting rod；Described rotation is controlled, selects as required so that both increased material movement distance, improves again heating rate.

2. a kind of semi continuous microwave catalysis pyrolysis reactor according to claim 1, it is characterized in that: described in add the structure in hot cell on cross section for regular hexagon, outdoor totally 9, the three groups of microwave heating sources of fate cloth of heating, and each heating source axis of each group is all misaligned, adds hot cell and three microwave heating sources are installed on a lateral surface.

3. a kind of semi continuous microwave catalysis pyrolysis reactor according to claim 1, it is characterized in that: described microwave heating source is arranged on the outer rim adding hot cell, extend to and add hot cell, each heating source is all on different level, stepped it is distributed in the outer rim adding hot cell, to reduce interfering between heating source.

4. a kind of semi continuous microwave catalysis pyrolysis reactor according to claim 1, it is characterized in that: can catalyst filling inside described catalytic unit, carrying out catalysis upgrading with the gas that pyrolytic reaction is produced, the outlet of described catalytic unit is connected to the gas outlet adding hot cell.

5. a kind of semi continuous microwave catalysis pyrolysis reactor according to claim 1, it is characterized in that: described in add the top in hot cell and bottom is respectively arranged with a point for measuring temperature, described point for measuring temperature adopts non-contact infrared temperature sensor, point for measuring temperature can be selected as required neatly to carry out thermometric.