CN113105917A

CN113105917A - Multistage gasifier device of biomass fluidized bed

Info

Publication number: CN113105917A
Application number: CN202110287930.XA
Authority: CN
Inventors: 文志勇
Original assignee: Individual
Current assignee: Individual
Priority date: 2021-03-17
Filing date: 2021-03-17
Publication date: 2021-07-13

Abstract

The invention provides a biomass fluidized bed multistage gasification furnace device, which comprises: the fluidized bed multi-stage gasification furnace is divided into a lower-stage high-temperature combustion chamber, a middle-stage high-temperature pyrolysis chamber and a higher-stage steam gasification chamber. The outlet at the top of the fluidized bed multistage gasification furnace is connected with a steam-cooled spiral pipe wall type cyclone separation device, low-temperature steam enters a steam-cooled spiral pipe type cyclone separator to collect produced high-quality biochar/active carbon, and the separator cools gasified gas and biomass carbon particles; the gasification gas leaves the gasifier through the cartridge. The slag is collected by a slag discharge pipe. The invention produces high-heat value gasified gas and high-quality biomass charcoal/active carbon by various technical means such as biomass gasification, flow adjustment and the like, thereby realizing the maximization of economic value.

Description

Multistage gasifier device of biomass fluidized bed

Technical Field

The invention relates to a fluidized bed multistage gasification device in the technical field of biomass gasification.

Background

Biomass is a precious green low-pollution renewable resource on the earth, biomass gasification furnaces are various in forms, and the problems that materials wind spiral feeding blades and block feeding pipes often occur to the existing normal-pressure fluidized bed gasification furnace. The problems that the gasification temperature is too high, the low-melting-point alkali metal and salt are melted at high temperature and adhered to a furnace wall to coke, or biomass tar generated by low-temperature gasification is adhered to materials to block a blast cap, so that the fluidized combustion and gasification operation safety are influenced occur. The existing normal-pressure fluidized bed gasification furnace can not simultaneously and efficiently gasify various biomasses with large water difference and large heat value difference. The gasified gas and high-temperature materials after the gas-solid high-temperature separation of the traditional separator need subsequent cooling.

The multi-stage gasification device of the biomass fluidized bed utilizes non-mechanical feeding, and can avoid the feeding from winding a spiral blade and avoiding blockage. The fluidized bed is utilized for multi-stage gasification, so that the gasification temperature and the fluidization speed can be controlled, and coking in the gasification furnace is avoided. Controlling the biomass charging amount, oxidizing air and gasifying steam proportion, and regulating the fuel value of the gasifying gas and the biomass carbonization degree and proportion. The biomass fluidized bed multistage gasification device is suitable for gasification of different types of biomass, is suitable for operation under different working conditions, is adjusted to produce corresponding high-quality biomass charcoal/activated carbon, produces high-calorific-value gasified gas, and enlarges the material application range of the gasification furnace. The biomass energy production value is improved.

Disclosure of Invention

The invention mainly solves the technical problem of providing a biomass fluidized bed multistage gasification furnace device, which adopts a non-mechanical feeding, biomass multistage gasification and steam cooling spiral pipe wall type cyclone separator to solve the problems in the background technology.

In order to solve the technical problems, the invention adopts a technical scheme that: provided is a biomass fluidized bed multistage gasification furnace device comprising: the fluidized bed multi-stage gasification furnace is divided into a lower-stage high-temperature combustion chamber, a middle-stage high-temperature pyrolysis chamber and a higher-stage steam gasification chamber. The feeding device of the fluidized bed multistage gasifier is non-mechanical feeding, so that the problems of spiral blade winding and blockage of raw materials are avoided, a gasified gas outlet at the top of the fluidized bed multistage gasifier is connected to a steam-cooled spiral wall type cyclone separator, the steam-cooled spiral wall type cyclone separator collects particle materials on the lower part of a conical pipe through the centrifugal force, and clean gasified gas leaves the gasifier through a core barrel. The low-temperature steam is uniformly distributed to the wall type spirally-ascending pipelines in the lower header to cool the high-temperature fuel gas and the biochar particles. The side wall of the air chamber is provided with a fluidized air inlet and a start-stop replacement steam inlet, and an air distribution bed is arranged between the air chamber and the combustion chamber, so that combustion air is uniformly introduced into the combustion chamber to fluidize and combust materials. The combustion chamber is big end down's toper structure, and the antetheca feed inlet divide into two-layerly, and hot-air lets in the lower floor's feed pipe chute bottom, blows into the living beings granule of feed pipe chute input in the stove and burns and produce high temperature flue gas to atmoseal feed inlet. The biomass material enters the lower-level combustion chamber for fluidized combustion, the high-temperature material rises to a certain height and then is fully mixed with the fuel newly entering from the front wall feed inlet, and the high-temperature material falls back to the bottom of the combustion chamber along the furnace wall, so that the ignition temperature is increased, and the combustion is more stable and rapid. The high-temperature flue gas generated by the lower-level combustion chamber provides high-temperature pyrolysis temperature for the middle-level gasification, and the tar generated by the low-temperature gasification is prevented from attaching to the furnace wall to coke. And low-temperature steam is introduced to the bottom of the upper-layer feeding inclined pipe, biomass particles input by the feeding inclined pipe are blown into the furnace to absorb the temperature of high-temperature flue gas, and a feeding port is sealed in a steam mode. The biomass material enters the middle-stage pyrolysis chamber to be uniformly mixed with the high-temperature material and the flue gas flowing into the combustion chamber at a high speed, the biomass material is quickly pyrolyzed at a high temperature, the temperature of the flue gas at the upper part of the combustion chamber is reduced, alkali metals and salts thereof in the biomass are prevented from being melted and coked at a high temperature, and the gasification temperature is reached to prepare for subsequent steam gasification. A necking part is arranged between the middle-level pyrolysis chamber and the upper-level gasification chamber, and gasification steam is introduced from the necking part, so that high-temperature materials enter the gasification chamber to be fully fluidized, gasified and carbonized.

The biomass fluidized bed multistage gasification furnace device is characterized in that the fluidized bed multistage gasification furnace is divided into a lower-level high-temperature combustion chamber, a middle-level high-temperature pyrolysis chamber and a higher-level steam gasification chamber. The high-temperature flue gas generated by the lower-level combustion chamber provides high-temperature pyrolysis temperature for the middle-level gasification, and tar generated by low-temperature gasification is prevented from attaching to the furnace wall to coke. The high-temperature material and the flue gas flowing into the middle-stage pyrolysis chamber and the combustion chamber at a high speed are uniformly mixed and quickly pyrolyzed at a high temperature, the temperature of the flue gas at the upper part of the combustion chamber is reduced, alkali metals and salts thereof in the biomass are prevented from being melted and coked at a high temperature, and the gasification temperature is reached to prepare for subsequent steam gasification. A necking part is arranged between the middle-level pyrolysis chamber and the upper-level gasification chamber, and gasification steam is introduced from the necking part, so that high-temperature materials enter the upper-level gasification chamber to be fully fluidized, gasified and carbonized.

The cyclone separation device is a steam-cooled spiral pipe wall type cyclone separator which is composed of a conical steam-cooled spiral pipe wall type body, an upper collection box, a lower collection box and a core barrel, and a flue gas inlet of the steam-cooled spiral pipe wall type cyclone separation device is connected with a fuel gas outlet of the fluidized bed multistage gasification furnace through a pipeline. The low-temperature steam is uniformly distributed in the wall type spirally-ascending pipelines in the lower collecting box, the heating area of the steam is increased, the steam in the wall type pipe passes through different heat load areas in the spiral pipe, the steam is heated on the non-uniform heat load areas and tends to be balanced, the heat stress concentration is reduced, the welding joints of the wall type pipeline and the collecting box are reduced, and the cooling speed of the carbonized particles in the cyclone cylinder is higher and more balanced.

According to the biomass fluidized bed multistage gasification furnace device, the front wall feeding port is divided into two layers, hot air is introduced to the bottom of the lower layer feeding inclined pipe, biomass particles input by the feeding inclined pipe are blown into the furnace to be combusted to generate high-temperature flue gas, and the feeding port is sealed in an air mode. The bottom of the upper feeding inclined tube is filled with low-temperature steam, biomass particles input by the feeding inclined tube are blown into the furnace to absorb high-temperature flue gas temperature, and meanwhile, the temperature of the middle-level pyrolysis chamber is adjusted, and a feeding port is sealed by steam. The feeding in front of the furnace is non-mechanical feeding, so that the raw materials are prevented from being wound and adhered on the spiral blade and blocked in the operation process of the spiral feeder.

According to the biomass fluidized bed multistage gasification furnace device, the air distribution bed is uniformly provided with the air caps, the air inlets on the air caps are uniformly arranged obliquely downwards, and combustion and gasification air uniformly enters the air caps from the air chamber. The air sprayed from the blast cap reacts on the air distribution bed to form fluidized air, so that the biomass entering the lower-stage combustion chamber is fluidized and combusted, and the bed material at the bottom of the furnace is fluidized, thereby preventing the bed material from coking and blocking the blast cap. And bottom slag discharge ports are formed in two sides of the air distribution bed, so that the bottom slag can be continuously discharged to maintain normal combustion and gasification in the operation process.

According to the biomass fluidized bed multistage gasification furnace device, the control system adjusts feeding and air supply flow and gasification steam proportion, and controls the temperature and gasification speed of the lower-level high-temperature combustion chamber, the middle-level high-temperature pyrolysis chamber and the upper-level steam gasification chamber. Regulating the fuel value of gasified gas and the carbonization degree and quality of biomass.

A biomass fluidized bed multistage gasification furnace device comprises the following steps:

and (1) feeding the biomass raw material into a lower-stage combustion chamber of the fluidized bed multistage gasifier through high-temperature air at a lower-stage feeding port, performing combustion reaction under the action of fluidized air to generate high-temperature flue gas, and sealing the feeding port in an air manner. The biomass material enters the lower-level combustion chamber for fluidized combustion, the fluidized high-temperature material rises to a certain height and then is fully mixed with the fuel newly entering from the front wall feed inlet, and the fluidized high-temperature material falls back to the bottom of the combustion chamber along the furnace wall, so that the combustion is more stable and rapid due to the improvement of the ignition temperature.

And (3) the biomass in the step (2) is fed into the middle-level high-temperature pyrolysis chamber at the upper layer feeding port through low-temperature steam, and is rapidly pyrolyzed by high-temperature flue gas, so that tar produced by low-temperature gasification is prevented from attaching to the furnace wall to coke. Heating to steam gasification temperature, and adjusting the temperature of the combustion chamber to avoid over-high temperature coking of the combustion chamber.

The high-temperature material in the step (3) is brought into a top reducing port of the middle-stage high-temperature pyrolysis chamber by the fluidization flue gas, and the high-speed fluidization material is quickly mixed with high-temperature steam introduced from the throat part and then enters a higher-stage steam gasification chamber for gasification; large-particle materials are rolled and circularly gasified in the gasification chamber, so that the gasification time is prolonged, and coarse particles are gasified into fine particles; the fine particle material is rapidly carbonized in the gasification chamber during the ascending period.

Step (4), the high-temperature biomass gasified gas carrying the biochar enters a steam-cooled spiral tube wall type cyclone separator through a connecting pipeline for gas-solid separation; under the centrifugal action force, biomass carbon particles are collected by a wall type cyclone separator of a steam-cooling spiral pipe, and are cooled by low-temperature steam in a wall type pipeline to prepare for subsequent biomass carbon forming; clean fuel gas leaves the gasifier through the core barrel.

And (5) the combustion and gasification air enters the air distribution bed from the air chamber, uniform fluidized air is formed in the lower-stage combustion chamber, biomass is fluidized and combusted, and bed materials at the bottom of the furnace are fluidized, so that the bed materials are prevented from coking and blocking an air cap. And low slag discharge ports are formed in two sides of the air distribution bed, so that low slag can be continuously discharged in the operation process, and normal combustion and gasification can be maintained.

The invention has the beneficial effects that:

by adopting the multistage gasification device of the biomass fluidized bed and utilizing non-mechanical feeding, the feeding can be prevented from winding the spiral blade and being blocked.

The fluidized bed multi-stage gasification furnace is adopted to carry out lower-stage combustion, middle-stage high-temperature pyrolysis and upper-stage steam gasification on biomass materials, and the reaction temperature and speed are controlled in a multi-stage step mode, so that not only is coking caused by adhesion of low-temperature gasification tar to a furnace wall avoided, but also melting coking caused by overhigh gasification temperature of alkali metals and metal salts thereof is avoided. Can control the biomass material to be gasified stably and quickly, improve the carbonization quality and ensure the safe operation of the gasification furnace.

The steam-cooled spiral pipe wall type cyclone separator is adopted, low-temperature steam is uniformly distributed into the wall type spiral ascending arranged pipeline from the lower header, the steam heating area is increased, more wall type steam inside the pipe is heated on the non-uniform heat load area and tends to be balanced, the heat stress concentration is reduced, and the welding joint of the wall type pipeline and the header is reduced. The steam cooling pipeline is arranged by the steam cooling spiral pipe wall type separator, so that the carbonized particles in the cyclone cylinder are cooled more uniformly and more quickly. The waste heat of the fuel gas and the biochar is recycled, the heating area of a subsequent fuel gas-steam heat exchanger is reduced, and the space and the system material consumption are saved.

Controlling the biomass, the proportion of the oxidation air and the gasification steam, the fuel value of the gasification gas and the carbonization degree and proportion of the biomass. The biomass material is subjected to combustion, pyrolysis and steam gasification, the reaction temperature and speed are controlled in multiple steps, and the method is suitable for high-efficiency gasification and carbonization of various biomass materials with different moisture contents and different heat values in the same fluidized bed gasification furnace and has high value and capacity. The material application range of the gasification furnace is improved.

Drawings

FIG. 1 is a schematic structural view of a multi-stage gasification furnace apparatus of a biomass fluidized bed according to the present invention;

FIG. 2 is a schematic view of the structure of the steam-cooled spiral tube wall type cyclone separator of the present invention.

Claims

1. The utility model provides a multistage gasifier device of living beings fluidized bed which characterized in that: the fluidized bed multi-stage gasification furnace is divided into a lower-stage high-temperature combustion chamber, a middle-stage high-temperature pyrolysis chamber and an upper-stage steam gasification chamber; the feeding device is non-mechanical, a gasified gas outlet at the top of the fluidized bed multi-stage gasification furnace is connected with a steam-cooled spiral pipe wall type cyclone separation device, the steam-cooled spiral pipe wall type cyclone separation device collects particle materials at the lower part of the conical pipe through the centrifugal force, simultaneously cools the gasified gas and the particle materials, separates clean gasified gas and leaves the gasification furnace through a separator barrel, the side wall of the air chamber is provided with a fluidized air inlet and a start-stop replacement and adjustment steam inlet, and an air distribution bed is arranged between the air chamber and the combustion chamber to uniformly fluidize the materials; the combustion chamber is big-end-up's taper structure, and the antetheca feed inlet divide into two-layerly, and the living beings granule of lower floor's feed pipe chute input blows in the stove burning and produces high temperature flue gas, provides the pyrolysis temperature for middle level pyrolysis chamber, and the living beings granule of upper strata feed pipe chute input blows in the stove and absorbs high temperature flue gas temperature, and quick pyrolysis reduces combustion chamber upper portion flue gas temperature, is the throat between middle level pyrolysis chamber and the higher level gasification chamber, and gasification steam introduces gasification chamber from throat and fully fluidizes, gasification carbonization high temperature material.

2. The fluidized bed multistage gasification furnace according to claim 1, wherein the lower stage high temperature combustion chamber generates high temperature flue gas to provide high temperature pyrolysis temperature for the intermediate stage gasification; the biomass raw material enters the middle-stage high-temperature pyrolysis chamber, is uniformly mixed with the fluidized material and the high-temperature flue gas of the lower-stage high-temperature combustion chamber, is rapidly pyrolyzed at high temperature, a throat is formed between the middle-stage pyrolysis chamber and the upper-stage gasification chamber, and gasification steam is introduced from the throat, so that the high-temperature material enters the upper-stage gasification chamber to be sufficiently fluidized, gasified and carbonized.

3. The non-mechanical feed device of claim 1, wherein: the front wall feeding port is divided into an upper layer and a lower layer, hot air is introduced into the bottom of the lower layer feeding inclined pipe, biomass particles are blown into the furnace to be combusted to generate high-temperature flue gas, and the feeding port is sealed by air; the upper feed pipe chute bottom lets in low temperature steam, blows in the interior absorption high temperature flue gas temperature of stove with the living beings granule, and the fast pyrolysis adjusts middle level pyrolysis chamber temperature simultaneously to the atmoseal feed inlet.

4. The vapor-cooled spiral duct wall cyclone furnace unit of claim 1, further comprising: the separator is composed of an annular lower-stage box, an upper collecting box and a pipe wall type body, low-temperature steam is introduced to cool gasified gas and biomass charcoal particles entering the cyclone separator, gas-solid separation is carried out while cooling products to recover waste heat, the temperature of the gasified gas is improved, gasification strength and quality are improved, waste heat is recovered, heat efficiency is improved, equipment is simplified for cooling subsequent gasified products, and the site is saved.

5. The cyclone separation device as claimed in claim 4, wherein a plurality of pipes are led out from the annular lower header, the pipes are wound to form a lower cone upper cylindrical winding type spiral ascending pipe wall type body, the lower cone upper cylindrical winding type spiral ascending pipe wall type body is connected to the annular upper header, low-temperature steam is uniformly distributed in the lower header to the pipes arranged in the wall type spiral ascending way, the heating area of the steam is increased, the steam in the wall type pipe is subjected to different heat load areas in the spiral pipe, the steam is heated to be balanced in the non-uniform heat load areas, the heat stress concentration is reduced, the welding joints of the wall type pipe and the header are reduced, and the cooling speed of carbonized particles in the.

6. The air distribution bed of claim 1, wherein: the air distribution bed is uniformly provided with air caps, air inlets on the air caps are obliquely and uniformly arranged downwards, combustion and gasification air uniformly enters each air cap from an air chamber, air sprayed out of the air caps reacts on the air distribution bed to form fluidized air, biomass entering a lower-stage combustion chamber is fluidized and combusted, furnace bottom bed materials are fluidized, the coking of the bed materials and the blockage of the air caps are prevented, bottom slag discharge ports are formed in two sides of the air distribution bed, and the bottom slag can be continuously discharged to maintain normal combustion and gasification in the operation process.

7. The control system of claim 1, wherein: the control system controls feeding, air supply flow and gasification steam proportion, adjusts the temperature of the lower-level high-temperature combustion chamber, the middle-level high-temperature pyrolysis chamber and the upper-level water steam gasification chamber and the gasification speed in the furnace, and adjusts the fuel value of the gasified gas and the carbonization degree and quality of the biomass.

8. The subordinate biomass combustion temperature of claim 1 is 950 ℃ to 1200 ℃.

9. The intermediate-stage high-temperature pyrolysis temperature of the high-temperature pyrolysis method is 800-1100 ℃ according to claim 1.

10. The upper stage steam gasification temperature of claim 1 is 600 ℃ to 950 ℃.