CN110079342A - A kind of method and apparatus of biomass pyrogenation gasification hydrogen manufacturing co-production coke - Google Patents

Abstract

The invention discloses a kind of method and apparatus of biomass pyrogenation gasification hydrogen manufacturing co-production coke, biomass generates volatile matter and hot coke through pyrolysis processing；The volatilization lease making gas solid separation removes coke granule；The thin coke that the hot coke and gas-solid separate obtains cold coke through cooling treatment；The gasification temperature of the volatile matter and vapor is 600-700 DEG C, through CO₂Absorbent and catalyst gasification generate hydrogen-rich gas；The hydrogen-rich gas is purified and obtains dry hydrogen-rich gas after being dried, and the present invention will be pyrolyzed and gasification is classified, the coke of realization biomass pyrolytic volatile matter high-efficiency gasification hydrogen manufacturing co-production high added value.

Description

A kind of method and device for biomass pyrolysis gasification hydrogen production and coke production

technical field

The invention belongs to the technical field of biomass energy, and in particular relates to a method and a device for producing hydrogen by biomass pyrolysis gasification and concurrently producing coke.

Background technique

Biomass pyrolysis gasification for hydrogen production is an important development direction for the efficient conversion and high-value utilization of biomass. According to the different gasification medium, it is mainly divided into air gasification, oxygen gasification, air-steam gasification, oxygen-steam gasification, and water vapor gasification. Compared with other gasification technologies, biomass steam gasification is easier to obtain higher _H2 concentration and yield, and has received extensive attention.

The reaction temperature of biomass steam gasification is generally between 700-800 °C, and the concentration of _H2 in the produced gas can reach 40-50%. By increasing the gasification temperature (such as 850 °C and above) or further introducing catalysis (such as natural Ore and nickel-based catalyst, etc.), the concentration of _H2 in the product gas can be further increased, but generally not more than 60%. The further increase of H ₂ concentration is limited by the thermodynamic balance of chemical reaction, and the produced gas still contains a large amount of carbon-containing gases such as CO, CO ₂ , CH ₄ and a small amount of tar.

Some studies have shown that by adding a CO ₂ absorbent in the gasification process, the CO ₂ generated during the gasification process can be removed in situ, which can promote the gasification reaction to move in the direction of generating more H ₂ , thereby obtaining higher H 2. ₂ concentration and yield, the hydrogen production process is also known as _CO2 capture-based biomass gasification hydrogen production process. However, this hydrogen production process still has the following problems: 1) The biomass carbon conversion rate is low, and the H ₂ yield still needs to be improved. This is mainly due to the fact that the suitable temperature for calcium-based absorbent _CO2 absorption under normal pressure is between 600-700 °C, and the biomass steam gasification reaction rate is relatively low in this temperature range; 2) biomass coke and volatilization There is an order of magnitude difference in the gasification rate of biomass ash, and it is difficult to achieve high-efficiency conversion at the same time; 3) The mixing of biomass ash and calcium-based absorbent in the gasification process will significantly affect its _CO absorption performance and subsequent recycling.

SUMMARY OF THE INVENTION

According to the problems existing in the prior art, the present invention proposes a method and a device for biomass pyrolysis gasification hydrogen production and coke production in parallel. High-efficiency gasification for hydrogen production and coke production with high added value.

The technical scheme adopted in the present invention is as follows:

A method of biomass pyrolysis gasification for hydrogen production and coke production, wherein biomass is pyrolyzed to generate volatile matter and hot coke; the volatile matter is separated from gas-solid to remove coke particles; the hot coke and gas-solid are separated The fine coke that comes down is cooled to obtain cold coke; the gasification temperature of the volatile matter and water vapor is 600-700 ° C, and the gasification of CO ₂ absorbent and catalyst generates hydrogen-rich gas; the hydrogen-rich gas is purified. and drying to obtain dry hydrogen-rich gas.

Further, the CO ₂ absorbent is a calcium-based CO ₂ absorbent, specifically, nano-calcium oxide, quicklime, calcined dolomite, modified calcium oxide, supported calcium-based absorbent and the like can be used.

Further, the catalyst is a nickel-based catalyst.

Further, the value range of the mass ratio of the CO ₂ absorbent and the catalyst is: 1-10:1.

A device for biomass pyrolysis gasification hydrogen production and coke production, comprising a biomass pyrolysis reactor, the inlet end of the biomass pyrolysis reactor is connected to a silo, and the outlet of the biomass pyrolysis reactor is connected to a silo. The ends are respectively connected to the coke cooler and the gas-solid separator, the solid discharge port and the gas discharge port of the gas-solid separator are respectively connected to the coke cooler and the volatile gasification reactor, and the volatile gasification reactor is provided with CO ₂ absorbent and catalyst; the outlet of the volatile gasification reactor is sequentially connected to a gas purifier and a gas dryer;

Further, the biomass pyrolysis reactor is a spiral pyrolysis reactor, and a heater is provided outside the biomass pyrolysis reactor;

Further, the coke cooler is a screw conveyor with a water-cooled jacket;

Further, the volatile gasification reactor is an externally heated fixed bed reactor.

Beneficial effects of the present invention:

The method and device for coke production and coke production by biomass pyrolysis gasification proposed in the present invention separate coke and volatile gasification through pyrolysis and gasification classification, and directly co-produce coke products, while avoiding biomass The ash content in the next-stage volatile matter gasification process affects the performance of the calcium-based absorbent, and the calcium-based absorbent and catalyst are simultaneously introduced in the volatile matter steam gasification process. The CO ₂ , concentrates the H ₂ in the product gas, and promotes the balance to move in the direction of generating more H _2. On the other hand, the catalyst improves the gasification reaction rate and carbon conversion rate of volatile components, so as to obtain high H ₂ higher _H2 yields were obtained at the same concentration.

Description of drawings

Fig. 1 is a kind of device schematic diagram of biomass pyrolysis gasification hydrogen production co-producing coke of the present invention;

In the figure, 1, silo; 2, biomass pyrolysis reactor; 3, gas-solid separator; 4, coke cooler; 5, volatile gasification reactor; 6, gas purifier; 7, gas dryer .

Detailed ways

In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention, but not to limit the present invention.

As shown in Figure 1, a device for coke production by biomass pyrolysis gasification and coke production designed by the present invention includes: a biomass pyrolysis reactor 2, and an inlet end connecting material of the biomass pyrolysis reactor 2 At the outlet of warehouse 1, biomass pyrolysis reactor 2 is a spiral pyrolysis reactor, and the spiral pyrolysis reactor is a single-screw pyrolysis reactor or a double-screw pyrolysis reactor; the spiral pyrolysis reactor adopts an external heating method, including Electric heating, high temperature flue gas heating, etc. The upper end of the outlet of the biomass pyrolysis reactor 2 is connected to the gas-solid separator 3 , and the lower end of the outlet of the biomass pyrolysis reactor 2 is connected to the inlet of the coke cooler 4 . The solid discharge port at the bottom of the gas-solid separator 3 is connected to the inlet of the coke cooler 4, and the coke cooler 4 is a screw conveyor with a water-cooled jacket; the gas discharge port at the top of the gas-solid separator 3 is connected to the volatile gasification reactor 5, An absorbent and a catalyst are arranged inside the volatile gasification reactor 5, and the absorbent and the catalyst can be directly mixed for use; it is also possible to use a solid carrier such as γ-Al ₂ O ₃ to support both CaO and Ni on the carrier, A composite catalytic absorber CaO-Ni/γ-Al ₂ O ₃ is formed, which is reused and the volatile gasification reactor 5 is an externally heated fixed-bed reactor, and its heating methods include electric heating, high-temperature flue gas heating, and microwave radiation heating etc.; the outlet of the volatile gasification reactor 5 is connected to the gas purifier 6 and the gas dryer 7 in sequence.

A method for coke production by biomass pyrolysis gasification and hydrogen production proposed by the present invention is based on the above designed device for biomass pyrolysis gasification hydrogen production and coke production in parallel. The specific process of the method is as follows:

The biomass enters the biomass pyrolysis reactor 2 at 400-700 °C for pyrolysis treatment to generate volatile matter and hot coke; The coke and fine-grained coke enter the coke cooler 4, and are cooled to obtain a cold coke product below 50°C; the volatile matter and water vapor after gas-solid separation are passed into the volatile matter gasification reactor 5 at 600-700°C , through the gasification of the _CO2 absorbent and catalyst mixture in the volatile gasification reactor 5 or the composite catalytic absorbent bed containing _CO2 absorbent and catalyst components to generate wet hydrogen-rich gas, and the wet hydrogen-rich gas passes through the gas After purification and drying by the purifier 6 and the gas dryer 7, a dry hydrogen-rich gas product is obtained.

The gas-solid separation method of the gas-solid separator 3 includes cyclone separation, inertial separation, gravity separation, and the like.

The CO ₂ absorbent is a calcium-based CO ₂ absorbent, including nano-calcium oxide, quicklime, calcined dolomite, modified calcium oxide, supported calcium-based absorbent, etc. The catalyst is a nickel-based catalyst. The composite catalytic absorbent is a composite catalytic absorbent containing calcium oxide and nickel active components. CO ₂ absorbent and catalyst mixture or composite catalytic adsorbent containing CO ₂ absorbent and catalyst components, in terms of mass ratio, absorbent:catalyst=10:1.

The calcined dolomite (calcium-based CO ₂ absorbent) and the Ni/γ-Al ₂ O ₃ catalyst were mixed uniformly in a mass ratio of 5:1, and 5 kg of the mixed catalyst/absorbent sample was weighed and placed into the volatile gasification reaction in advance. device 5. The pre-crushed and sieved corn stalk particles to 0.2-0.4 mm were dried at 105° C. for 2 hours and then loaded into the biomass silo 1 . The temperature of biomass pyrolysis reactor 2 (500°C) and volatile gasification reactor 5 (650°C) were raised to the set temperature under the condition of _N2 carrier gas flow rate of 5L/min and stabilized, and then water vapor was introduced. And set its flow rate to 3kg/h. Subsequently, the biomass feed was started for pyrolysis at a biomass feed rate of 1 kg/h. The biomass is pyrolyzed to produce volatile matter and coke, and the volatile matter enters the volatile matter gasification reactor 5 after passing through the primary cyclone separator for _CO2 absorption and enhanced steam catalytic gasification for hydrogen production. The hot coke produced by the biomass pyrolysis reactor 2 and the fine coke separated by the gas-solid separator 3 are cooled together by the gas-solid separator 4 with a water-cooling jacket, and the cooling water flow rate is 1L/min. The gas produced by the gasification of the volatiles passes through the purifier 6 to absorb tar and moisture by using a solvent, and the dryer 7 uses activated carbon to adsorb and dry to obtain a dry hydrogen-rich gas product.

The volume fraction of _H2 in the hydrogen-rich gas product finally obtained in this example is as high as 85.1%, the yield is 80 g/kg biomass, the volume fraction of CO is 5.1%, the volume fraction of _CO2 is 0.1%, and the volume fraction of _CH4 is 9.7 %, the coke mass yield was 31%. Compared with the prior art, the method and device of the present invention can greatly improve the H ₂ yield, and the device of the present invention can separate the gasification of coke and volatile matter, and directly co-produce coke.

In order to explain the technical scheme protected by the present invention more clearly, the following is further explained in conjunction with the specific working process of the present invention:

The above embodiments are only used to illustrate the design ideas and features of the present invention, and the purpose is to enable those skilled in the art to understand the contents of the present invention and implement them accordingly, and the protection scope of the present invention is not limited to the above embodiments. Therefore, all equivalent changes or modifications made according to the principles and design ideas disclosed in the present invention fall within the protection scope of the present invention.

Claims (8)

1. a method for biomass pyrolysis gasification to produce hydrogen and co-producing coke, it is characterized in that, biomass produces volatile matter and hot coke through pyrolysis treatment; Described volatile matter is removed coke particle through gas-solid separation; The hot coke and the fine coke separated from the gas and solid are cooled to obtain cold coke; the gasification temperature of the volatile matter and water vapor is 600-700 ° C, and the hydrogen-rich gas is generated by the gasification of the CO ₂ absorbent and the catalyst; The hydrogen-rich gas is purified and dried to obtain a dry hydrogen-rich gas. 2 . The method of biomass pyrolysis gasification for hydrogen production and coke production according to claim 1 , wherein the CO ₂ absorbent is a calcium-based CO ₂ absorbent. 3 . 3 . The method of biomass pyrolysis gasification for hydrogen production and coke production according to claim 1 , wherein the catalyst is a nickel-based catalyst. 4 . 4 . The method for producing hydrogen by biomass pyrolysis and gasification and co-producing coke according to claim 1 , wherein the mass ratio of the _CO absorbent and the catalyst ranges from 1 to 10:1. 5 . 5. A device for coke production based on biomass pyrolysis gasification and hydrogen production according to any one of claims 1 to 4, characterized in that it comprises a biomass pyrolysis reactor (2), wherein the The inlet end of the biomass pyrolysis reactor (2) is connected to the silo (1), and the outlet end of the biomass pyrolysis reactor (2) is respectively connected to the coke cooler (4) and the gas-solid separator (3), so the The solid discharge port and the gas discharge port of the gas-solid separator (3) are respectively connected to the coke cooler (4) and the volatile gasification reactor (5), and the volatile gasification reactor (5) is provided with CO _2. Absorber and catalyst; the outlet of the volatile gasification reactor (5) is connected to a gas purifier (6) and a gas dryer (7) in sequence. 6 . The device for coke production by biomass pyrolysis gasification and coke production according to claim 5 , wherein the biomass pyrolysis reactor (2) is a spiral pyrolysis reactor, and the biomass pyrolysis reactor (2) is a A heater is provided outside the material pyrolysis reactor (2). 7 . The device of biomass pyrolysis gasification hydrogen production and coke production according to claim 5 , wherein the coke cooler ( 4 ) is a screw conveyor with a water cooling jacket. 8 . 8 . The device for biomass pyrolysis and gasification for hydrogen production and coke production according to claim 5 , wherein the volatile gasification reactor ( 5 ) is an externally heated fixed-bed reactor. 9 .