阅读说明：本技术 一种生物质颗粒燃料脱水炭化处理工艺 (Dehydration and carbonization treatment process for biomass granular fuel ) 是由 洪楚城 张育文 于 2019-09-20 设计创作，主要内容包括：本发明提供一种生物质颗粒燃料脱水炭化处理工艺,涉及生物质颗粒燃料技术领域,包括以下步骤：对生物质原料进行挑选和清理,并进行风干处理,除去原料中的外在水份,将风干后的原料进行粉碎,得原料颗粒；向原料颗粒中加入(NH<Sub>4</Sub>)H<Sub>2</Sub>PO<Sub>4</Sub>粉末,混合搅拌均匀,将混合颗粒置于管式炉中,对混合颗粒进行脱水稳定化预处理,结束后,取出混合粉末,采用三段炭化工艺对混合颗粒进行炭化处理,在氮气气氛下冷却至120℃以下取出,完成炭化处理,得生物质颗粒燃料。经脱水炭化处理后得到的生物质颗粒燃料能有效避免生物质在炭化过程中出现膨化粘连情况,炭化效果好,炭产率大,能源得率高。燃烧时需要的活化能低,综合燃烧特性好。(The invention provides a biomass granular fuel dehydration carbonization treatment process, which relates to the technical field of biomass granular fuels and comprises the following steps of selecting and cleaning biomass raw materials, carrying out air drying treatment to remove external moisture in the raw materials, crushing the air-dried raw materials to obtain raw material granules, adding (NH 4 ) H 2 PO 4 powder into the raw material granules, mixing and stirring uniformly, placing the mixed granules in a tubular furnace, carrying out dehydration stabilization pretreatment on the mixed granules, taking out the mixed powder after the dehydration stabilization pretreatment, carrying out carbonization treatment on the mixed granules by adopting a three-stage carbonization process, cooling to a temperature below 120 ℃ in a nitrogen atmosphere, taking out the mixed granules, and completing carbonization treatment to obtain the biomass granular fuel.)

1. A biomass granular fuel dehydration carbonization treatment process is characterized by comprising the following steps:

1) Selecting and cleaning biomass raw materials, removing waste impurities which do not meet production requirements, air-drying the biomass raw materials which meet the production requirements, removing external moisture in the raw materials, and crushing the air-dried raw materials to obtain raw material particles;

2) adding (NH ₄) H ₂ PO ₄ powder into the raw material particles, and uniformly mixing and stirring to obtain mixed particles;

3) Placing the mixed particles in a tubular furnace, heating the mixed particles from room temperature to 190 ℃ in an inert atmosphere, preserving the heat for a period of time, performing dehydration stabilization pretreatment on the mixed particles, taking out the mixed powder after the dehydration stabilization pretreatment is finished, and placing the mixed powder in a drying dish to cool the mixed powder to the room temperature;

4) and (3) placing the mixed powder treated in the step 3) into a tubular furnace, and carbonizing the mixed particles by adopting a three-stage carbonization process, specifically, increasing the temperature to 220 ℃ for heat preservation for 15-20min, then increasing the temperature to 300 ℃ for heat preservation for 15-20min, finally increasing the temperature to 400 ℃ for heat preservation for 15-20min, cooling to below 120 ℃ in a nitrogen atmosphere, and taking out to finish carbonization treatment to obtain the biomass particle fuel.

2. The biomass pellet fuel dehydration and carbonization treatment process as claimed in claim 1, wherein in step 1), the air drying treatment is performed to control the water content of the raw material to be 21-30%, and the crushed raw material pellets are sieved through a 240-300 mesh sieve.

3. the biomass pellet fuel dehydration carbonization treatment process of claim 1, wherein the addition amount of the (NH ₄) H ₂ PO ₄ powder in step 2 is 1/80-1/100 of the mass of the raw material pellet.

4. the biomass pellet fuel dehydration and carbonization treatment process as claimed in claim 1, wherein in step 3), the temperature rise rate is 3-6 ℃/min, and the temperature is kept for 6-12 h.

5. the biomass pellet fuel dehydration and carbonization treatment process of claim 1, wherein before the step 4) is started, nitrogen is introduced into the tube furnace for 20min, and the nitrogen flow is 2L/min.

6. the biomass pellet fuel dehydration and carbonization treatment process according to claim 1, wherein in the step 4), the temperature rise rate of the first two times is 1 ℃/min, and the temperature rise rate of the last time is 2 ℃/min.

Technical Field

The invention relates to the technical field of biomass pellet fuels, in particular to a biomass pellet fuel dehydration and carbonization treatment process.

background

In recent years, the economic efficiency of China is rapidly increased, the consumption of fossil fuels is increased year by year, and the problem of energy shortage is increasingly serious. The biomass energy is the fourth largest energy which is second to coal, petroleum and natural gas in the total energy consumption in the world at present as renewable energy. As a big agricultural country, China has abundant biomass varieties and a large number of biomass varieties. The biomass mainly refers to straws except grains and fruits in the production process of agriculture and forestry, lignocellulose such as trees and the like, agricultural product processing industry leftovers, agricultural and forestry wastes, livestock and poultry manure and wastes in the production process of animal husbandry and the like. The potential of biomass energy resources in China is reduced to about 7 hundred million tons of standard coal through huge investigation, but the actual use amount of the biomass energy resources in the current year is only about 2.2 hundred million tons of standard coal. The development of biomass resources can relieve the energy crisis of China and reduce the emission of pollutants, and the biomass resources contain a large amount of macromolecular substances with special structures such as carbon-rich cellulose, hemicellulose, lignin and the like, and are rich raw materials for preparing various carbon materials.

Biomass carbonization is one of important technologies for efficiently utilizing biomass resources, and carbonization is a process of heating to high temperature under the condition of isolation or a little air to enable biomass materials to generate physical and chemical changes. The biomass carbonization process has low requirements on raw materials, is simple and has low energy consumption. Compared with the original biomass, the biomass charcoal has the advantages of greatly improved energy density, convenient storage and transportation and wide application. Compared with coal, the biomass charcoal has low ash content and nitrogen and sulfur element content, low emission of combustion pollutants and remarkable emission reduction of carbon dioxide, and is a better alternative fuel.

In the prior art, biomass particle fuel is dehydrated and carbonized, the particles usually have the phenomena of bulking and adhesion, the subsequent forming treatment is inconvenient, the carbon yield is low, and the carbonization efficiency is not high.

disclosure of Invention

Technical problem to be solved

aiming at the defects of the prior art, the invention provides a biomass pellet fuel dehydration and carbonization treatment process, the biomass pellet fuel obtained after dehydration and carbonization treatment can effectively avoid the puffing adhesion condition of biomass in the carbonization process, and has good carbonization effect, high carbon yield and high energy yield.

(II) technical scheme

In order to achieve the purpose, the invention is realized by the following technical scheme:

a biomass granular fuel dehydration carbonization treatment process comprises the following steps:

1) Selecting and cleaning biomass raw materials, removing waste impurities which do not meet production requirements, air-drying the biomass raw materials which meet the production requirements, removing external moisture in the raw materials, and crushing the air-dried raw materials to obtain raw material particles;

2) Adding (NH ₄) H ₂ PO ₄ powder into the raw material particles, and uniformly mixing and stirring to obtain mixed particles;

3) placing the mixed particles in a tubular furnace, heating the mixed particles from room temperature to 190 ℃ in an inert atmosphere, preserving the heat for a period of time, performing dehydration stabilization pretreatment on the mixed particles, taking out the mixed powder after the dehydration stabilization pretreatment is finished, and placing the mixed powder in a drying dish to cool the mixed powder to the room temperature;

4) and (3) placing the mixed powder treated in the step 3) into a tubular furnace, and carbonizing the mixed particles by adopting a three-stage carbonization process, specifically, increasing the temperature to 220 ℃ for heat preservation for 15-20min, then increasing the temperature to 300 ℃ for heat preservation for 15-20min, finally increasing the temperature to 400 ℃ for heat preservation for 15-20min, cooling to below 120 ℃ in a nitrogen atmosphere, and taking out to finish carbonization treatment to obtain the biomass particle fuel.

Further, in the step 1), the water content of the raw material is controlled to be 21-30% through air drying treatment, and the crushed raw material particles are sieved through a 240-fold 300-mesh sieve.

Further, in the step 2), the addition amount of the (NH ₄) H ₂ PO ₄ powder is 1/80-1/100 of the mass of the raw material particles.

Further, in the step 3), the temperature rising rate is 3-6 ℃/min, and the temperature is kept for 6-12 h.

further, before the step 4) is started, nitrogen is introduced into the tube furnace for 20min, and the nitrogen flow rate is 2L/min.

Further, in the step 4), the temperature rising speed of the first two times is 1 ℃/min, and the temperature rising speed of the last time is 2 ℃/min.

(III) advantageous effects

The invention provides a biomass pellet fuel dehydration carbonization treatment process, which can effectively avoid the puffing adhesion condition of biomass in the carbonization process, and has the advantages of good carbonization effect, high carbon yield and high energy yield.

the (NH ₄) H ₂ PO ₄ powder and (NH ₄) H ₂ PO ₄ are added into the biomass raw material to react with alkali metals in the biomass to generate a high-melting-point compound, so that the precipitation of the alkali metals is inhibited, the carbon yield can be improved, biomass particles can have higher heat value and energy density, low O/C ratio and moisture content by dehydration stabilization pretreatment, and meanwhile, the adhesion phenomenon of expansion of the biomass particles in the carbonization process can be avoided, the original appearance of the biomass particles is kept to the maximum extent, and the subsequent molding, storage and transportation are facilitated.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the embodiments of the present invention, and it is obvious that the described embodiments are some embodiments of the present invention, but not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.