CN115011394A - Macadimia nut peel and shell based high-strength high-combustibility biomass granular fuel and preparation method thereof - Google Patents

Abstract

The invention relates to the technical field of resource utilization of biomass pellet fuel and agricultural wastes, in particular to macadimia nut peel and shell-based high-strength high-combustibility biomass pellet fuel and a preparation method thereof. The biomass granular fuel comprises peel and shell of macadamia nut, a combustion improver, a sulfur fixing agent and a cementing agent; the grain sizes of the peel and the shell of the macadimia nut are less than 1 mm; mixing the peel and the shell of the macadimia nut according to the mass ratio of 2: 1-2: 2. The invention provides a high-calorific-value and high-combustibility biological granular fuel with stable mechanical property and good corrosion resistance.

Description

High-strength and high-combustibility biomass pellet fuel based on macadamia nut peel and husk and preparation method

technical field

The invention relates to the technical field of biomass granule fuel and agricultural waste resource utilization, in particular to a high-strength and high-combustibility biomass granule fuel based on macadamia nut peel and husk and a preparation method.

Background technique

Biomass pellet fuel can be used as an alternative to fossil fuels and can be used in energy supply systems designed for fossil fuels. On the one hand, it can meet the growing energy demand to a certain extent, and on the other hand, it can reduce the emission of harmful gases during the combustion process. The fuel is pressed into particles with regular shape and size, which increases the density, reduces the volume, improves the mechanical strength of the fuel, and is convenient for transportation and storage. In addition, granular biofuels can reduce dust, reduce the risk of explosion, and have higher safety.

At present, the main macadamia producing areas and macadamia primary processing plants in Yunnan Province are relatively concentrated, and the peels and husks are easier to collect as processing by-products, which can provide a stable source of raw materials for the production of biomass pellet fuel. The content of acid-insoluble lignin in the husk of macadamia nuts reaches about 40%, which is higher than that of ordinary wood and has better anti-corrosion properties. Nutshells contain a variety of volatile substances with aroma, and the pellet fuel can be used as fuel for the production of flue-cured tobacco, bacon and roasted tea, which can make the food have a more unique flavor. However, in the prior art, there is no method for preparing biomass fuel by using the peel and husk of macadamia nuts as raw materials.

SUMMARY OF THE INVENTION

The invention provides a high-strength and high-combustibility biomass pellet fuel based on macadamia nut peel and husk and a preparation method, which are used to solve the problem that there is no method in the prior art to prepare biomass fuel from macadamia nut peel and husk as raw materials. Defects, realize the resource utilization of macadamia nut peel and husk, and provide a high calorific value and high combustibility biological particle fuel with stable mechanical properties and good anti-corrosion properties. The present invention obtains high-performance bio-particle fuel with high calorific value under simple process conditions.

The present invention provides a biomass particle fuel, which comprises the peel and husk of macadamia nuts, a combustion accelerant, a sulfur-fixing agent and a cementing agent;

The particle size of the peel and the husk of the macadamia is less than 1 mm;

The peel and husk of the macadamia nuts are mixed in a mass ratio of 2:1 to 2:2.

Preferably, the peel and husk of the macadamia nuts are placed in a semi-air-dried or completely air-dried state for a period of time after the kernels are taken out through food processing. Since the peel and husk of the macadamia nuts that are placed for a period of time under natural ventilation after processing have low water content, the above manufacturing process saves the link of drying and dehydration of raw materials.

According to the biomass pellet fuel provided by the present invention, the water content of the peel is 10-40%;

Preferably, the water content of the peel is 10-30%.

According to the biomass pellet fuel provided by the present invention, the water content of the husk is 8-22%.

According to the biomass pellet fuel provided by the present invention, the added amount of the combustion-supporting agent accounts for 0.5-2% of the total mass of the husk and peel.

Preferably, the combustion aid is sodium carbonate and/or sodium bicarbonate.

According to the biomass pellet fuel provided by the present invention, the added amount of the sulfur-fixing agent accounts for 1-3% of the total mass of the husk and peel.

Preferably, the sulfur-fixing agent is calcium carbonate and/or slaked lime.

According to the biomass pellet fuel provided by the present invention, the added amount of the binder accounts for 2-6% of the total mass of the husk and the peel.

Preferably, the binder is industrial water glass.

According to the biomass particle fuel provided by the present invention, the particle size of the biomass particle fuel is controlled between 5 and 15 mm.

The present invention also provides a method for preparing the above-mentioned biomass particle fuel, comprising the following steps:

(1) Mixed granulation material: Mix the peel and husk of the macadamia nut, and add a combustion accelerant, a sulfur-fixing agent and a cementing agent.

(2) Pressing the mixed material into a biomass pellet fuel. The preparation method of the invention has the advantages of simple process, low energy consumption, low cost and the like. The biomass pellet fuel produced by the invention has good combustion performance, low combustion pollution, and is convenient for transportation and storage. Meanwhile, the products prepared only by the preparation method of the present invention can be used in the food processing industry, such as the production links of flue-cured tobacco, roasted tea and bacon.

According to the preparation method of biomass pellet fuel provided by the present invention, in step (2), the pressure of compression molding is controlled between 20-60 MPa.

According to the preparation method of biomass pellet fuel provided by the present invention, in step (2), the temperature of compression molding is controlled between 40-65°C. The pressure and temperature required in the pellet pressing and forming process of the present invention are lower than other technologies for preparing biomass fuel. The preparation method of the biomass particle fuel of the present invention has lower preparation difficulty and more energy saving.

Preferably, the preparation method of biomass particle fuel comprises the following steps:

(1) Crushing of raw materials: Crushing the macadamia nut peel and husk.

(2) Mixed granulation material: mix the pulverized macadamia nut skin and nut shell, and add a combustion accelerant, a sulfur-fixing agent and a cement;

The combustion-supporting agent is sodium bicarbonate or sodium carbonate; the sulfur-fixing agent is calcium carbonate or slaked lime; the cementing agent is industrial water glass;

(3) Pressing the mixed material into a biomass pellet fuel.

Preferably, the pulverized macadamia nut skin and husk are stored under dry and ventilated conditions for later use.

Preferably, the granulator is used for compression molding.

Beneficial effects of the present invention:

(1) The main raw materials used in this technology come from biomass, and the reagents used in combustion accelerants, binders and sulfur-fixing agents are all non-toxic reagents. Therefore, the macadamia nut peel and husk-based high-strength and high-combustibility biomass pellet fuel prepared by this technology can be used in the food processing industry, such as the production links of flue-cured tobacco, roasted tea and bacon, and can make roasted or smoked food Has a more unique flavor.

(2) Due to the high content of lignin in the husk of the raw macadamia nut, the preservative performance of the pellet fuel is improved, and the process of adding preservatives is omitted compared with other technologies.

(3) In the present invention, a combustion accelerant, a cementing agent and a sulfur-fixing agent are added. The biomass pellet fuel has excellent combustion performance, stable mechanical performance is convenient for transportation and storage, and the sulfur-containing gas pollution produced by combustion is reduced.

(4) The preparation technology of macadamia nut peel and husk-based high-strength and high-combustibility biomass pellet fuel provides a new way for the consumption and resource utilization of macadamia nut peel and husk.

(5) In the present invention, the peel and husk of macadamia nuts are used as raw materials, and after adding a certain amount of cementing and anti-corrosion materials, the pellets are pressed into pellets to produce high calorific value and high flammability biological pellet fuels with stable mechanical properties and good anti-corrosion properties. The invention provides a simple, low-carbon high-calorific value biological particle fuel manufacturing technology.

Detailed ways

In order to make the objectives, technical solutions and advantages of the present invention clearer, the technical solutions in the present invention will be described clearly and completely below. Obviously, the described embodiments are a part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

In view of the defect in the prior art that there is no use of the peel and husk of macadamia to prepare biomass fuel, the present invention pulverizes the peel and husk of macadamia nuts and mixes them according to a certain proportion, and the water content after mixing is controlled within a specific range Inside. A certain amount of sulfur-fixing agent, cementing agent and combustion accelerant is added into the mixture, and then mixed, and pressed into biomass pellet fuel under certain pressure and temperature conditions. The process of the invention has the advantages of simple flow, low energy consumption, low cost and the like. The biomass pellet fuel produced by the invention has good combustion performance, low combustion pollution, and is convenient for transportation and storage. At the same time, the products prepared by this technology can be used in the food processing industry, such as the production links of flue-cured tobacco, roasted tea and bacon.

Example 1

A macadamia nut peel and husk-based high-strength and high-combustibility biomass pellet fuel and a preparation method, comprising the following steps:

(1) Pulverize the macadamia nut peel (water content 39.8%) and husk (water content 17.8%) that have been placed for 3 days after processing to less than 0.5 mm, and store in dry and ventilated conditions for later use.

(2) Mix the crushed macadamia nut skin and nut shell in a ratio of 2:1 (weight ratio). Add 0.6% (weight ratio) of sodium bicarbonate as combustion-supporting agent, add 1.2% (weight ratio) amount of slaked lime as sulfur-fixing agent, add 3% (weight ratio) industrial water glass as binding agent, and make after fully mixing. into a mixed material.

(3) Compression molding using a granulator. The pressure of compression molding was controlled at 40MPa, the temperature was 45°C, and the fuel particle size was 10mm.

Example 2

A macadamia nut peel and husk-based high-strength and high-combustibility biomass pellet fuel and a preparation method, comprising the following steps:

(1) Pulverize the macadamia nut peel (water content 29.2%) and husk (water content 16.8%) that have been placed for 8 days to less than 0.85 mm, and store in dry and ventilated conditions for later use.

(2) Mix the pulverized macadamia nut skin and nut shell in a ratio of 2:2 (weight ratio). Add 1% (weight ratio) of sodium carbonate as combustion-supporting agent, add 2% (weight ratio) amount of slaked lime as sulfur-fixing agent, add 3.5% (weight ratio) industrial water glass as cementing agent, and make after fully mixing Mixed material.

(3) Compression molding using a granulator. The pressure of compression molding was controlled at 55MPa, the temperature was 58°C, and the fuel particle size was 15mm.

Example 3

A macadamia nut peel and husk-based high-strength and high-combustibility biomass pellet fuel and a preparation method, comprising the following steps:

(1) Pulverize the macadamia nut peel (water content 13.8%) and husk (9.6%) that have been air-dried under natural conditions to less than 0.45mm, and store in dry and ventilated conditions for later use;

(2) Mix the pulverized macadamia nut skin and nut shell according to the ratio of 2:1.5 (weight ratio), add 1.2% (weight ratio) of sodium carbonate as a combustion aid, add 1.8% (weight ratio) amount of carbonic acid Calcium is used as a sulfur-fixing agent, and 3.3% (weight ratio) of industrial water glass is added as a cementing agent, which is fully mixed to make a mixed material;

(3) Compression molding using a granulator, the compression molding pressure is controlled to be 48MPa, the temperature is 60°C, and the fuel particle size is 12mm.

Comparative Example 1

A method for preparing biomass fuel by utilizing macadamia nut production waste, comprising the following steps:

(1) Pulverize the macadamia nut peel that has been air-dried under natural conditions to less than 0.8 mm, and store it under dry and ventilated conditions for later use.

(2) Add 2% (weight ratio) of sodium carbonate as combustion-supporting agent, add 1.6% (weight ratio) sodium ethylenediamine acetate, add 3.3% calcium chloride, and make mixed material after fully mixing.

(3) Compression molding using a granulator. The pressure of compression molding was controlled to be 60MPa, and the temperature was 70°C.

Comparative Example 2

A method for preparing biomass fuel by utilizing macadamia nut production waste, comprising the following steps:

(1) Mix the pruned branches and leaves of the macadamia nuts that have been placed for a period of time with the husk in a mass ratio of 3:1 (weight ratio).

(2) Pulverize the mixture of branches and husks to less than 1.5 mm, store in dry and ventilated conditions for later use.

(3) add 0.8% (weight ratio) rosin emulsion, add 2% (weight ratio) concentration of ferric nitrate aqueous solution of 0.07mol/L, add 4.2% (weight ratio) calcium chloride, make after fully mixing Mixed material.

(4) Compression molding using a granulator. The pressure of compression molding is controlled at 80MPa, the temperature is controlled at 95°C, and the particle size is controlled at 20mm.

Comparative Example 3

A method for preparing biomass fuel by utilizing macadamia nut production waste, comprising the following steps:

(1) Pulverize the macadamia nut shell that has been placed for a period of time to less than 0.8mm, and store it under dry and ventilated conditions for later use.

(2) 1.8% (weight ratio) phosphoric acid is added, 3% (weight ratio) sodium chloride is added, and 3.3% sodium hydroxide is added, and the mixed material is prepared after fully mixing.

(3) Compression molding using a granulator. The pressure of compression molding is controlled at 95MPa, the temperature is controlled at 55°C, and the particle size is controlled at 15mm.

Comparative Example 4

A macadamia nut peel and husk-based high-strength and high-combustibility biomass pellet fuel and a preparation method, comprising the following steps:

(1) Pulverize the macadamia nut peel (water content 39.8%) and husk (water content 17.8%) that have been placed for 3 days after processing to less than 0.5 mm, and store in dry and ventilated conditions for later use.

(2) Mix the crushed macadamia nut skin and nut shell in a ratio of 4:1 (weight ratio). Add 0.6% (weight ratio) of sodium bicarbonate as combustion-supporting agent, add 1.2% (weight ratio) amount of slaked lime as sulfur-fixing agent, add 3% (weight ratio) industrial water glass as binding agent, and make after fully mixing. into a mixed material.

(3) Compression molding using a granulator. The pressure of compression molding was controlled at 40MPa, the temperature was 45°C, and the fuel particle size was 10mm.

Comparative Example 5

A macadamia nut peel and husk-based high-strength and high-combustibility biomass pellet fuel and a preparation method, comprising the following steps:

(1) Pulverize the macadamia nut peel (water content 29.2%) and husk (water content 16.8%) that have been placed for 8 days to less than 0.85 mm, and store in dry and ventilated conditions for later use.

(2) Mix the pulverized macadamia nut skin and nut shell in a ratio of 1:5 (weight ratio). Add 1% (weight ratio) of sodium carbonate as combustion-supporting agent, add 2% (weight ratio) amount of slaked lime as sulfur-fixing agent, add 3.5% (weight ratio) industrial water glass as cementing agent, and make after fully mixing Mixed material.

(3) Compression molding using a granulator. The pressure of compression molding was controlled at 55MPa, the temperature was 58°C, and the fuel particle size was 15mm.

The biomass pellet fuels prepared in Examples 1-3 and Comparative Examples 1-5 were tested. Refer to GB/T 30727 for low calorific value test on received basis, NY/T 1881.2 for total moisture (as received basis) test, NY/T 1881.5 for ash content (dry basis) test, and NY/T 1881.8 for crushing rate test. The results are shown in Table 1.

Table 1 Biomass pellet fuel performance test results

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, but not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that it can still be The technical solutions described in the foregoing embodiments are modified, or some technical features thereof are equivalently replaced; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims (10)

1. a biomass particle fuel, is characterized in that, comprises the pericarp and husk of macadamia nut, combustion-supporting agent, sulfur-fixing agent and cementing agent; The particle size of the peel and the husk of the macadamia is less than 1 mm; The peel and husk of the macadamia nuts are mixed in a mass ratio of 2:1 to 2:2. 2. The biomass pellet fuel according to claim 1, wherein the water content of the peel is 10-40%; Preferably, the water content of the peel is 10-30%. 3 . The biomass pellet fuel according to claim 1 , wherein the water content of the husk is 8-22%. 4 . 4. The biomass pellet fuel according to claim 1, wherein the added amount of the combustion-supporting agent accounts for 0.5-2% of the total mass of the husk and peel; preferably, the combustion-supporting agent is sodium bicarbonate and / or sodium carbonate. 5. The biomass pellet fuel according to claim 1, wherein the added amount of the sulfur-fixing agent accounts for 1-3% of the total mass of the husk and peel; preferably, the sulfur-fixing agent is calcium carbonate and/or slaked lime. 6 . The biomass pellet fuel according to claim 1 , wherein the added amount of the binder accounts for 2-6% of the total mass of the husk and peel; preferably, the binder is industrial water glass. 7 . 7 . The biomass pellet fuel according to claim 1 , wherein the particle size of the biomass pellet fuel is controlled between 5 and 15 mm. 8 . 8. A method for preparing biomass pellet fuel according to any one of claims 1-7, characterized in that, comprising the following steps: (1) Mixed granulation material: mix the peel and husk of the macadamia nut, add a combustion accelerant, a sulfur-fixing agent and a cement; (2) Pressing the mixed material into a biomass pellet fuel. 9 . The method for preparing biomass pellet fuel according to claim 8 , wherein, in step (2), the pressure of pressing is controlled between 20 and 60 MPa. 10 . 10 . The method for preparing biomass pellet fuel according to claim 8 , wherein, in step (2), the temperature of pressing and molding is controlled between 40 and 65° C. 11 .