CN111253988A - Preparation method of clean biomass briquette - Google Patents

Preparation method of clean biomass briquette Download PDF

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Publication number
CN111253988A
CN111253988A CN202010102681.8A CN202010102681A CN111253988A CN 111253988 A CN111253988 A CN 111253988A CN 202010102681 A CN202010102681 A CN 202010102681A CN 111253988 A CN111253988 A CN 111253988A
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biomass
coal
briquette
biomass briquette
binder
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李�浩
孙天逸
吴圆圆
马悠然
黄浩
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Hebei University of Technology
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Hebei University of Technology
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    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10L—FUELS NOT OTHERWISE PROVIDED FOR; NATURAL GAS; SYNTHETIC NATURAL GAS OBTAINED BY PROCESSES NOT COVERED BY SUBCLASSES C10G, C10K; LIQUEFIED PETROLEUM GAS; ADDING MATERIALS TO FUELS OR FIRES TO REDUCE SMOKE OR UNDESIRABLE DEPOSITS OR TO FACILITATE SOOT REMOVAL; FIRELIGHTERS
    • C10L5/00—Solid fuels
    • C10L5/02—Solid fuels such as briquettes consisting mainly of carbonaceous materials of mineral or non-mineral origin
    • C10L5/06—Methods of shaping, e.g. pelletizing or briquetting
    • C10L5/10—Methods of shaping, e.g. pelletizing or briquetting with the aid of binders, e.g. pretreated binders
    • C10L5/14—Methods of shaping, e.g. pelletizing or briquetting with the aid of binders, e.g. pretreated binders with organic binders
    • C10L5/16—Methods of shaping, e.g. pelletizing or briquetting with the aid of binders, e.g. pretreated binders with organic binders with bituminous binders, e.g. tar, pitch
    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10L—FUELS NOT OTHERWISE PROVIDED FOR; NATURAL GAS; SYNTHETIC NATURAL GAS OBTAINED BY PROCESSES NOT COVERED BY SUBCLASSES C10G, C10K; LIQUEFIED PETROLEUM GAS; ADDING MATERIALS TO FUELS OR FIRES TO REDUCE SMOKE OR UNDESIRABLE DEPOSITS OR TO FACILITATE SOOT REMOVAL; FIRELIGHTERS
    • C10L5/00—Solid fuels
    • C10L5/40—Solid fuels essentially based on materials of non-mineral origin
    • C10L5/44—Solid fuels essentially based on materials of non-mineral origin on vegetable substances
    • C10L5/442—Wood or forestry waste
    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10L—FUELS NOT OTHERWISE PROVIDED FOR; NATURAL GAS; SYNTHETIC NATURAL GAS OBTAINED BY PROCESSES NOT COVERED BY SUBCLASSES C10G, C10K; LIQUEFIED PETROLEUM GAS; ADDING MATERIALS TO FUELS OR FIRES TO REDUCE SMOKE OR UNDESIRABLE DEPOSITS OR TO FACILITATE SOOT REMOVAL; FIRELIGHTERS
    • C10L9/00—Treating solid fuels to improve their combustion
    • C10L9/10—Treating solid fuels to improve their combustion by using additives
    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10L—FUELS NOT OTHERWISE PROVIDED FOR; NATURAL GAS; SYNTHETIC NATURAL GAS OBTAINED BY PROCESSES NOT COVERED BY SUBCLASSES C10G, C10K; LIQUEFIED PETROLEUM GAS; ADDING MATERIALS TO FUELS OR FIRES TO REDUCE SMOKE OR UNDESIRABLE DEPOSITS OR TO FACILITATE SOOT REMOVAL; FIRELIGHTERS
    • C10L10/00—Use of additives to fuels or fires for particular purposes
    • C10L10/14—Use of additives to fuels or fires for particular purposes for improving low temperature properties
    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10L—FUELS NOT OTHERWISE PROVIDED FOR; NATURAL GAS; SYNTHETIC NATURAL GAS OBTAINED BY PROCESSES NOT COVERED BY SUBCLASSES C10G, C10K; LIQUEFIED PETROLEUM GAS; ADDING MATERIALS TO FUELS OR FIRES TO REDUCE SMOKE OR UNDESIRABLE DEPOSITS OR TO FACILITATE SOOT REMOVAL; FIRELIGHTERS
    • C10L2290/00—Fuel preparation or upgrading, processes or apparatus therefore, comprising specific process steps or apparatus units
    • C10L2290/32—Molding or moulds
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E50/00—Technologies for the production of fuel of non-fossil origin
    • Y02E50/10—Biofuels, e.g. bio-diesel
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E50/00—Technologies for the production of fuel of non-fossil origin
    • Y02E50/30—Fuel from waste, e.g. synthetic alcohol or diesel

Abstract

The invention relates to a preparation method of clean biomass briquette. The method comprises the following steps: mixing coal, biomass and a binder, drying at 105-115 ℃ for 9-11 h, taking out, tabletting under the pressure of 9-11 MPa, and drying at 100-110 ℃ for 1-2 h to obtain biomass briquette; wherein the mass ratio is coal: and (3) biomass binder is 4-8: 1-3: 1-3; the granularity of the biomass is 50-70 meshes; the binder is biological tar; the biomass is wood chips. The invention can solve the treatment of waste biological tar and wood chips, improve the performance of coal, reduce environmental pollution and realize the reutilization of energy.

Description

Preparation method of clean biomass briquette
Technical Field
The invention relates to the field of agricultural resource utilization and the technical field of energy and chemical industry, in particular to clean biomass briquette coal taking agricultural and forestry waste biomass as a raw material and a preparation technology thereof.
Background
China is a country rich in coal, poor in oil and less in gas, so that the position of coal as main energy cannot be changed in a short time, and in actual production, the yield of pulverized coal is huge and cannot be efficiently utilized. Therefore, a pulverized coal molding technique is indispensable for efficiently and cleanly utilizing low-rank pulverized coal. The biomass resource is wide in source, renewable, free of secondary pollution and low in price. Biomass energy is particularly important when fossil energy such as coal, oil, natural gas, etc. is used up. In recent years, many scholars at home and abroad use biomass as a binder to prepare moulded coal (the product formed by powdered coal is called moulded coal), and certain research results are obtained.
Share Lei et al found that lignin in biomass was partially dissolved and bonded with pulverized coal, improving the strength of biomass briquette. Guoshengkun and the like research on the influence of a starch binder in briquettes, and the results show that NaOH solution modified starch is more beneficial to briquette forming, but the use of NaOH not only increases the operation cost, but also causes serious alkali pollution to the environment if the used NaOH is directly discharged, and then the treatment needs to additionally increase the process flow and equipment, so that the original intention of green energy conservation is not practiced.
Inorganic binders such as clay have the obvious disadvantage of having a low calorific value by themselves; organic binders such as asphalt, sodium humate. Although having a high calorific value, the thermal stability is poor. Asphalt is generally considered to have good bonding effect, but still has the problem of environmental pollution. The sodium humate needs to be heated and melted when in use, has irritation and is easy to cause secondary pollution, and sodium ions are harmful to soil; the composite adhesive can fully exert the advantages of various adhesives and make up for the defects of a single adhesive, but the research on the aspect is less. The biomass and industrial and agricultural wastes have wide sources and the characteristics of good caking property and small environmental pollution, thereby drawing wide attention and being the development direction of briquette coal caking agents.
Disclosure of Invention
The invention aims to provide a preparation method of clean biomass briquette aiming at the defects in the prior art. According to the method, the biological tar is used as a binder, and the biomass wood chips and the coal powder are mixed to obtain the high-efficiency clean biomass briquette. By-product biological tar is inevitably generated in the process of biomass pyrolysis and gasification, and if the biological tar is involved in the preparation of the biomass briquette, on one hand, the treatment of the waste biological tar can be solved, and on the other hand, the reutilization of energy is also realized.
The technical scheme of the invention is as follows:
a preparation method of biomass briquette comprises the following steps:
mixing coal, biomass and a binder, drying at 105-115 ℃ for 9-11 h, taking out, tabletting under the pressure of 9-11 MPa, and drying at 100-110 ℃ for 1-2 h to obtain biomass briquette;
wherein the mass ratio is coal: and (3) biomass binder is 4-8: 1-3: 1-3; the granularity of the biomass is 50-70 meshes;
the binder is biological tar;
the biomass is wood chips.
The invention has the beneficial effects that:
the biomass briquette has the advantages of reduced relaxation ratio, increased compressive strength and increased falling strength, and has excellent performance compared with anthracite. Compared with anthracite, the biomass briquette is superior to anthracite in combustion characteristic, flammability and ignition stability, and has better combustion performance. Compared with anthracite, the ignition point of the biomass briquette is reduced, the minimum ignition energy is reduced, the biomass briquette is easy to ignite, and the biomass briquette saves more energy.
The biomass briquette prepared by using the novel adhesive biological tar has the characteristics of tight combination of molecules, high efficiency and cleanness. The biomass is a byproduct in the production process of agriculture and forestry, mainly comprises straws, sawdust and the like of crops, and has low cost and easy obtainment of raw materials. The invention uses the clean coal technology taking the biomass briquette as the breakthrough, is beneficial to improving the ignition performance of the briquette and reducing the environmental pollution, converts the biomass from useless and even harmful solid wastes into clean and efficient green energy, is beneficial to solving the problems of environmental pollution, low energy utilization rate and the like of the Chinese coal smoke type, and is a necessary choice for realizing sustainable development.
Drawings
FIG. 1 is an experimental flow chart for the preparation of a biomass briquette;
FIG. 2 is a thermal analysis diagram of anthracite coal in comparative example 1;
FIG. 3 is a thermogram of a biomass type coal in example 1;
FIG. 4 is a graph showing the compressive strength of anthracite coal in comparative example 1;
FIG. 5 is a graph of the compressive strength of the biomass briquette in example 1;
FIG. 6 is a graph showing the combustion characteristics of anthracite, biomass briquette and sodium humate coal;
Detailed Description
The invention is described in detail with reference to the accompanying drawings and examples, wherein the biomass briquette is produced by binding biomass and anthracite powder with a novel binder. Experimental procedures referring to fig. 1, in order to make the objects, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
The biological tar is straw gasified biological tar. The biomass gasification device is a downdraft gasification furnace, the gasification temperature is 900-1100 ℃, water vapor is selected as a gasification agent, the byproduct generated in the gasification process is waste polluted and corrosive biological tar, the appearance of the biological tar is black brown viscous liquid, and the biological tar has pungent smell.
Example 1:
weighing 0.2g of biological tar, adding 0.6g of anthracite powder, and stirring uniformly by using a glass rod;
step two, adding 0.2g of poplar wood chips of 60 meshes into the coal obtained in the step one, and stirring the mixture uniformly by using a glass rod;
and step three, drying the coal treated in the step two in an oven at 110 ℃ for 10h, placing the mixture in a tabletting mold, tabletting by using a powder tabletting machine under the pressure of 10MPa to obtain cylindrical briquette with the specification of phi 30mm, and drying at 105 ℃ for 2h to obtain the biomass briquette.
Comparative example 1:
step one, measuring 0.4g of poplar sawdust of 60 meshes, adding 0.6g of anthracite powder, and stirring uniformly by using a glass rod;
and step two, drying the coal treated in the step one in an oven at 110 ℃ for 10h, putting a certain amount of mixture in a tabletting mould, tabletting by using a powder tabletting machine under the pressure of 10MPa to obtain cylindrical shaped coal blocks with the specification of phi 30mm, and drying at 105 ℃ for 2h to obtain the anthracite.
The crushing or crumbling during the tabletting process can also be applied to the manufacture of finished products.
Common thermal analysis techniques are TG thermogravimetric analysis: the mass of the material was measured as a function of temperature under programmed temperature control. DTA differential thermal analysis: under the control of the program, the temperature is measured to change along with the program temperature, the exothermic effect is positively expressed according to the habit, and the endothermic effect is negatively expressed. As shown in the attached figures 2 and 3, the ignition point of the anthracite is about 520 ℃, the weight loss temperature of the TG curve is 400-800 ℃, and the DTA curve has an exothermic peak at 600-800 ℃. The ignition point of the biomass briquette is about 220 ℃, the weight loss temperature of a TG curve is 200-800 ℃, and a DTA curve has two obvious exothermic peaks at 350-500 ℃ and 500-800 ℃, which shows that the exothermic reaction of the biomass briquette is carried out in two steps.
Compared with TG-DTA curves of anthracite and biomass briquette, the anthracite has no exothermic reaction and the biomass briquette has obvious exothermic reaction at the temperature below 400 ℃. Compared with anthracite, the ignition point of the biomass briquette is reduced, the minimum ignition energy is reduced, the biomass briquette is easy to ignite, and the biomass briquette saves more energy.
As can be seen from tables 1 and 2 and accompanying figures 4 and 5, the biomass briquette has reduced relaxation ratio, increased compressive strength and increased drop strength, and has excellent performance compared with anthracite.
TABLE 1 drop Strength
Figure BDA0002387397780000031
TABLE 2 relaxation ratio
Figure BDA0002387397780000032
Comparative example 2:
the preparation of the sodium humate coal basically comprises the same steps as the example 1, except that the binder is sodium humate, and the coal: wood chip: the mass ratio of the sodium humate is 6: 2: 2.
humates and biomass are the binders which are currently studied more. Sodium humate, although having a high calorific value, still has a problem of environmental pollution. As shown in figure 6, the combustion effect of the biomass briquette is close to that of sodium humate coal, but the biological tar has the characteristics of environmental protection and cleanness; compared with anthracite, the biomass briquette is superior to anthracite in combustion characteristic, flammability and ignition stability, and has better combustion performance.
Example 2
The other steps are the same as the example 1, except that the mass ratio of coal: biomass binder 4: 2: 1. the combustion data of the biomass coal obtained is close to that of example 1.
Example 3
The other steps are the same as the example 1, except that the mass ratio of coal: biomass binder 8: 3: 1. the combustion data of the biomass coal obtained is close to that of example 1.
The market price of the current biological tar is about 400 yuan/ton, the market price of the anthracite powder is about 600 yuan/ton, and the market price of the sawdust is about 300 yuan/ton. The cost of 1 ton of biomass briquette is used for accounting, 0.6 ton of anthracite powder, 0.2 ton sawdust and 0.2 ton of biological tar are needed, and the estimated biomass briquette is about 500 yuan/ton. About 750 yuan anthracite coal is sold in one ton of market.
The heat value of anthracite is 6500 kilocalorie/kg, poplar wood chips are 4500 kilocalorie/kg, biological tar is 5800 kilocalorie/kg, and the heat value of biomass briquette is about 5940 kilocalorie/kg, namely 1 ton of biomass briquette is equivalent to 0.9 ton of anthracite, the heat value of coal is higher than that of biomass, but the heat value of the biomass briquette prepared by the method is closer to that of coal, and the biomass briquette can be used as a substitute for coal.
Burn 1 ton withoutBituminous coal discharging CO22.6 ton, SO224kg、NOx7 kg. The biomass is derived from plants and is generated by absorbing CO2 in the environment, so that the biomass briquette can offset with CO2 generated after combustion, and zero emission of CO2 can be realized. Namely 1 ton of biomass briquette coal for reducing the emission of 2.6 tons of CO2、6kg SO2、2.8kg NOx。
The unit cost of coal biological tar processed by the market is 151 yuan, wherein the unit cost is reduced by 25 yuan, so the cost is paid to 126 yuan/ton. The cost of 1 ton of biomass briquette is calculated, 0.2 x 126 is 25.2 yuan, and from the economic perspective, the cost for removing the biological tar can be saved by adopting the biological tar binder in the biomass briquette.
The analysis shows that compared with the traditional anthracite, the biomass briquette can effectively reduce the emission of environmental pollutants, and is superior to the anthracite on the whole in economy and environment by combining the consideration of pollutant emission.
The invention is not the best known technology.

Claims (2)

1. A preparation method of clean biomass briquette is characterized by comprising the following steps:
mixing coal, biomass and a binder, drying at 105-115 ℃ for 9-11 h, taking out, tabletting under the pressure of 9-11 MPa, and drying at 100-110 ℃ for 1-2 h to obtain biomass briquette;
wherein the mass ratio is coal: and (3) biomass binder is 4-8: 1-3: 1-3;
the binder is biological tar;
the biomass is wood chips.
2. The preparation method of the clean biomass briquette as claimed in claim 1, characterized in that the particle size of the biomass is 50-70 mesh.
CN202010102681.8A 2020-02-19 2020-02-19 Preparation method of clean biomass briquette Pending CN111253988A (en)

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Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101985575A (en) * 2010-11-05 2011-03-16 华南理工大学 Biomass moulded coal and preparation method thereof
CN102061209A (en) * 2011-01-24 2011-05-18 四川雷鸣生物环保工程有限公司 Production process of biomass pellet fuel and complete equipment
CN104449860A (en) * 2014-11-30 2015-03-25 东北电力大学 Solar heat collection pre-processing and gasified tar comprehensive utilization process and device used for biomass compression
CN107629828A (en) * 2017-08-26 2018-01-26 北京林业大学 A kind of method that forming charcoal is prepared using powdered carbon
JP2018165301A (en) * 2017-03-28 2018-10-25 Ｊｆｅスチール株式会社 Method for manufacturing binder for molded body, molded coal and coke and binder for molded body, molded coal, and coke

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101985575A (en) * 2010-11-05 2011-03-16 华南理工大学 Biomass moulded coal and preparation method thereof
CN102061209A (en) * 2011-01-24 2011-05-18 四川雷鸣生物环保工程有限公司 Production process of biomass pellet fuel and complete equipment
CN104449860A (en) * 2014-11-30 2015-03-25 东北电力大学 Solar heat collection pre-processing and gasified tar comprehensive utilization process and device used for biomass compression
JP2018165301A (en) * 2017-03-28 2018-10-25 Ｊｆｅスチール株式会社 Method for manufacturing binder for molded body, molded coal and coke and binder for molded body, molded coal, and coke
CN107629828A (en) * 2017-08-26 2018-01-26 北京林业大学 A kind of method that forming charcoal is prepared using powdered carbon

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