Corn stalk pellet machine

The following are the parameters and specifications of the corn stalk pellet machine for feed production:

Organic fertilizer corn stalk pellet machines and fuel corn stalk pellet machines belong to the same category, and both use model MZLH series pellet machine. But their capacity of pellets is different.

The following are the technical parameters of the corn stalk pellet machine for organic fertilizer:

There are fundamental differences between pellet fuel and feed, namely the quality requirements. Density is an indicator of the quality of pellet products. According to the literature, the density of feed pellet products is usually 0.5-0.75g/cm³. Compared with pellet fuel, the density requirements are relatively low.

Therefore, the pressure and temperature requirements of feed corn stalk pellet machines are not high, so the loss and life of core components are not as strict as those for pellet fuel.

Compared with feed pellets, fuel pellets have higher density requirements. Generally, the density is greater than the density of water. Therefore, the required pressure and temperature are also higher, so the loss and life of core components such as ring dies must be considered.

In addition, binders need to be added during the molding process of feed pellets, therefore, the requirements for the strength of core components are also reduced.

Therefore, the research on the ring-die corn stalk pellet machine for producing straw pellet fuel is not applicable to the corn stalk pellet machine for producing animal feed.

corn stalk pellet machine for livestock and poultry feed

corn stalk pellet machine for fuel

Next, take a Chinese corn straw pellet fuel production line project we have done as an example to conduct a simple economic benefit analysis. The designed annual production scale of this project is 6,000 tons/year.

(1) Consumption indicators and prices of main raw materials

At present, the price of corn straw per ton is 300 yuan (RMB). The price of water and electricity is estimated based on market prices. The following table lists the total consumption and price of corn straw pellet fuel raw materials and energy.

(2) Main raw material consumption indicators and prices

The moisture content of corn straw pellet fuel is calculated to be 21%. Because corn straw is lost during production, the calculation yield of raw materials is 65%. The company currently has 12 employees, with a monthly salary of 2,500 yuan per person.

(3) What are the economic benefits of turning corn straw into pellet fuel?

The production cost of corn straw pellet fuel is about 920 yuan per ton, and the Chinese market price is about 1,200 yuan per ton. In foreign markets, biomass pellet fuel is also very popular, with a price of 230 US dollars per ton. The net profit in China’s domestic market is approximately 280 yuan/ton, which has good economic benefits.

Break-even point calculation:

P=annual fixed cost/(annual sales revenue-annual total variable cost-sales tax and surcharges)=47.4%.

According to the break-even analysis, as long as the annual production capacity is not less than 47.4%, the company can achieve profitability and has a certain ability to resist risks.

(4) Benefit analysis

• Reduce the space ratio:
  The production process of corn straw fuel includes a corn stalk pellet machine system (compression molding process). The finished fuel is a high-density, lightweight corn stalk pellet product that is easy to package, transport, load, unload, and store, reducing transportation and storage costs for enterprises.
• Improve production efficiency:
  Due to the light weight of biomass briquette fuel, the labor intensity of workers during the feeding process is greatly reduced, and the labor cost per unit of energy is reduced.
• Fast burning speed:
  Biomass pellet ignite easily and burn quickly. Therefore, it can effectively increase the burning rate of a well-designed furnace, taking less time to release heat than coal does.
• Low cost of supporting facilities:
  Since most biomass contains extremely low sulfur content, combustion produces very little sulfur dioxide. Therefore, there is no need to install a separate desulfurization device, but only a flue gas dust removal device that meets national standards, thereby reducing the capital input of energy-consuming enterprises.
• High recovery rate of ash:
  The ash produced by the combustion of corn straw pellet fuel can be recycled and reused as fertilizer and chemical raw materials, thereby further reducing business costs. The ash contains elements such as magnesium, potassium, calcium, and sodium, and can be used as a high-quality crop fertilizer.
  The cinders produced after coal combustion have almost no use value, and the processing and optimization of cinders still require a certain cost. It can be seen that biomass briquette fuel has certain added value.
• Reduce carbon dioxide emissions:
  The carbon dioxide produced by burning biomass fuel comes from the raw material itself. Unlike fossil fuels, the increase in the total amount of carbon dioxide in the atmosphere comes from the burning of solid carbon in fossil fuels. The use of biomass pellet fuel reduces acid gas emissions, and biomass fuel has low sulfur characteristics.
  When they are burned, the emissions of acidic substances (such as sulfur dioxide) are much lower than fossil fuels, so they have no significant impact on air quality; the main pollutant when burning biomass pellet fuels is soot, and energy utilization companies can use efficient biomass burner, and install a dust removal device in the exhaust part to fully meet atmospheric emission standards.

As the demand for clean energy continues to increase due to economic development, the proportion of biomass pellets in the energy field will become higher and higher.

After scientific development, the rational utilization of biomass briquettes is an important manifestation of the energy industry. It could ameliorate the global energy shortage and over-reliance on coal, oil and other fossil fuels. It is an integral part of  clean energy sector.

Tests show that the calorific value of corn straw is similar to the calorific value of Class II bituminous coal. The surface of the corn straw pellet fuel produced by the corn stalk pellet machine system is smooth, and its physical properties fundamentally meet the requirements of transportation, packaging and storage.

As traditional fossil fuels gradually decline, biomass energy will play an important role. The development and development of biomass energy not only has obvious environmental benefits, but can also make up for the shortcomings of traditional energy sources.

• Compared with other biomass energy technologies, corn straw pellet fuel has a wide range of raw material sources, large output, low production cost, easy implementation, and good combustion performance. It is also the best product to replace electricity, oil, natural gas, and coal.
• The operating cost of corn straw pellets is low. As an efficient, energy-saving and environmentally friendly thermal energy, compared with fuel, natural gas and electricity, the operating cost can be saved by 40% to 50%.

• In the molding of corn stalks, as the compression ratio of the ring die increases, the density of the pellets increases, the energy consumption increases, and the output increases;
• when a certain compression ratio is reached, the density of the molded pellets increases less, the energy consumption increases accordingly, but the output decreases. dropped.

In a ring die with a compression ratio of 4.5, the corn straw particle size range is maintained at 1mm ~ 5mm, and the moisture content is maintained at 12% ~ 18%, the best effect is achieved. At this time, the pellet density and output are maximum and the energy consumption is small. (Find RICHI on YouTube)

The ring die corn stalk pellet machine compresses the corn straw pellets by pressing the straw pellets into the ring die holes through the pressure wheel, and the friction provided by the die holes causes extrusion to compress the corn straw pellets.

The ring die and pressure wheel are the core components of the corn stalk pellet machine.

Its working principle is that the motor drives the main shaft through the belt drive, and the main shaft drives the pressure wheel and the feed screw to rotate, and the biomass maize stover particles are pressed into the ring die through the rotation of the pressure wheel.

 In the ring die hole, in order to reduce the relative sliding between the biomass straw particles and the pressure wheel, certain teeth or grooves are processed on the outer surface of the pressure wheel.

Although there are two types of lamination molding, flat die and ring die, the ring die corn stalk pellet machine has become the mainstream model among the current pelleting machines due to its compact, simple structure and easy use. The ring die series corn stalk pellet machine has a higher output and is generally 0.6-10t/h, low energy consumption.

Moreover, the requirements for the properties of the biomass straw raw material itself are also lower, and the molding and curing effect is better. Compared with other models, the advantages are very obvious.

During the densification molding process of corn straw:

• When its density is less than 1.1g/cm³, its density is proportional to the pressure;
• When the density exceeds 1.1g/cm³, as the pressure continues to increase, the change in density is not obvious.
• When the pressure is low, the material is not extruded densely, the density of the molded block is small, the surface is rough, cracks are prone to occur, the strength is low, and the optimal density required for combustion cannot be achieved;
• When the pressure exceeds 60MPa, the density of the molded block is suitable, the surface quality is good, the strength is high, the molding effect is good, and the density of the molded block with good combustion effect is between 0.9~1.1g/cm³.

Comparing corn stalks and corn stalk pellets before and after compression, from the perspective of material combination, it is concluded that the raw material granules are combined in the form of a “solid bridge”. The increase in compression temperature can activate the effect of moisture, making the together with lignin, protein, starch and fat, it becomes a natural binder and helps in the formation of pellets.

Corn stover yields are large and widely distributed. Among its biomass components, up to 42% is carbon, which is considered a very reliable emerging fuel.

(1) Moisture content of raw materials

Different moisture contents affect the compression molding of biomass pellets. If the moisture content is too low or too high, it will have an adverse effect on the molding of corn stover biomass pellets.

If the moisture content is too high, the materials will fall apart and fail to form fuel. Generally speaking, the most suitable moisture content of raw materials is 12% to 15%.

(2) Heating temperature

Heating temperature is also one of the important factors affecting molding.

By heating, the lignin and other low molecular substances contained in the raw materials can be softened. The temperature at which the lignin softens plays an important role in bonding. In addition, high temperatures will also make the raw material itself softer and easier to compress.

(3) Pressure size

The main factor in forming corn stover biomass pellet fuel is compression, and the size of the pressure directly affects the molding effect.

• If the pressure is too high, the raw materials will be crushed;
• But if the pressure is too small, the corresponding product and its required performance will not be obtained. In the range of 200 bar~400 bar, it can meet the corn stalk pellet machine molding requirements of most raw materials, with smooth surface and moderate density.

(4) Fuel characteristics

From the perspective of corn stover biomass fuel production, it is first necessary to have a comprehensive understanding and mastery of the basic characteristics of corn straw, which is also one of the theoretical foundations of the corn straw pellet production process.

About 42% of the biomass component of corn stover is carbon, so it is a very reliable emerging fuel. The calorific value of corn straw is 15.55kJ/g, which belongs to the calorific value standard of Class II bituminous coal.

The application scope of corn straw pellet fuel mainly includes two aspects:

(1) On the one hand, in the industrial field, most waste can be reused and made into pellet fuel to replace non-renewable energy sources, such as coal, oil, etc., and can be used in waste-to-energy power plants, various industrial boilers, etc. Corn stover pellet fuel can be added to large boilers as fuel instead of having to use coal to produce flue gas as the plant’s source of heat energy.

• The dust removal rate and desulfurization rate of small and medium-sized boilers are lower than those of large coal-fired boilers. Therefore, small coal-fired boilers must be gradually banned. For thermal energy and natural gas users, using corn straw pellet fuel is a relatively economical choice. Part of the purchased raw materials replaces coal, and the other part is processed into corn based straws pellet fuel. This can not only reduce business costs, but also reduce environmental pollution;
• Carbonized corn straw pellet fuel is subjected to secondary activation treatment to produce industrial activated carbon that can be widely used.

(2) On the other hand, in terms of people’s livelihood, corn straw pellet fuel made by corn stalk pellet machine is suitable for cooking and heating. In some cold countries, corn stalk pellet fuel is used for heating, which not only reduces fuel costs, but also achieves environmental protection effects. Comprehensive applications in countries around the world include the following aspects:

• In cities, it can be used for heating in hotels and restaurants, and can also be used in small restaurants to replace the use of coal. In northern cities, it can be used as collective heating for residents, and can also be used as fireplace fuel in villas.
• In rural areas, with the improvement of farmers’ living standards, the demand for high-quality energy is also increasing. Using densification molding technology to process straw into pellet fuel and use it for heating can reduce farmers’ heating costs and significantly reduce rural demand for energy. dependence on other energy sources;
• After the corn straw pellet fuel is carbonized, it can be used as barbecue, hot pot fuel and hand warmer instead of charcoal;
• Application of charcoal powder in fields can effectively increase soil temperature, soil fertility and prevent pests and diseases.

In general, under the same pressure, small-sized raw materials have greater compression and are easier to shape.

It can be seen from the principle of dense molding that the density of molding is mainly affected by the degree of mutual extrusion between straw particles and filling of the gaps between materials.

• The smaller the size of the particles, the easier they are to fill, and the greater the attraction and bonding force between particles. Therefore, under the same pressure, the bonding between particles is easier, which results in the molded product having high density, smooth surface, high strength and good molding effect;
• As the size of the straw material becomes larger, the filling capacity between the particles becomes lower, the contact between the particles becomes looser, the degree of embedding between the particles becomes worse, and the attraction between the particles becomes smaller. These will ultimately lead to the molding effect of the straw material poor.

Therefore, the corn stalk biomass pellet mill machine has high requirements for the crushed raw materials. Tests show that the raw materials with a length greater than 6mm should be less than 10%, and the molding rate is high, so it has higher requirements for crushing.

Corn straw is the most important type of biomass that can be used.

RICHI used the corn stalk pellet machine system to test the power consumption of corn straw molding under different working conditions and found the lowest molding rate of corn straw.

The working conditions of electricity consumption provide a basis for the improvement of corn straw pelletizing process and the optimization design of molding equipment, and then provide scientific data for the pretreatment technology of large-scale resource utilization of biomass.

1. When forming corn straw pellets, the power consumption is mainly concentrated in the two processes of crushing and pelleting. The power consumption accounts for more than 90% of the total power consumption, and the power consumption of pelleting is twice that of crushing. Therefore, the pelleting process should be the core during process design to minimize power consumption, thereby effectively reducing the power consumption of corn stalk molding.
2. The density of corn stover biomass pellet fuel has a great impact on the power consumption during corn stalk pellet machine pelleting. Without affecting the use of corn stalk pellet fuel, the density requirements should be reduced as much as possible.

As a resource, crop straw can be used as fertilizer, feed, domestic fuel and raw material for industrial and sideline production.

(1) As fertilizer

Crop straw is mainly used as fertilizer in two aspects: direct utilization and processing utilization. Direct utilization generally takes the method of returning straw directly to the field, and processing and utilization mainly uses straw to compost organic fertilizer.

(2) As feed

In addition to direct feeding of crop straw as feed, there are also methods such as silage yellowing, ammoniation and saccharification.

Pools or plastic bags, etc., can achieve centralized and large-scale processing. In recent years, the use of specialized corn stalk feed pellet machine and equipment or straw feed production lines to process straw into pellet feed has developed rapidly.

(3) Others

Crop straws are also used as culture media for cultivating edible fungi, papermaking, producing fiber density boards, plant mulch films, tableware, packaging materials, seedling bowls, etc., as well as using straws to make chemical raw materials such as alcohol and refined starch.

This technology mainly uses a straw crusher to crush the straw after it is dried in the sun. Add other additives and mix well. After pouring into the hopper of the corn stalk pellet machine for feed, it is extruded by the grinding plate and the pressure wheel to form pellet feed.

Due to the friction and heating during the processing, the internal maturity of the maize stover is deep and transparent. The surface of the processed corn stalk pellet feed is smooth, with moderate hardness and consistent size. The diameter of the feed pellets can be adjusted according to the processing specifications.

The application of a complete set of corn stalk pellet machine plant can automatically complete the functions of straw crushing, lifting, stirring and feeding in sequence, and various effective additives can be added at any time, fully enclosed production, and high production efficiency.

At present, many small and medium-sized straw pellet feed processing enterprises adopt this technology. In addition, RICHI can also provide complete sets of straw concentrate feed processing and production technology suitable for large-scale feed production enterprises, with a higher level of automation control.

This technology uses high-temperature bacterial strain preparations to quickly compost wheat, corn, rice and other crop straws into efficient, high-quality organic fertilizer, which can then be processed into organic fertilizer granules using a straw organic fertilizer corn stalk pellet machine.

The principle is to use the bacterial strain preparations and various enzymes in the quick-corrosion agent to violently move at a certain humidity (about 65% of the water holding capacity of the straw) and a certain temperature (50°C ~ 70°C) to release energy.

• On the one hand, the fiber and protein of the straw will be quickly decomposed;
• On the other hand, a large amount of bacterial protein is formed, which is directly absorbed by plants or converted into humus.

Through combustion test research, it was found that the two types of pellet fuels can continue to burn for about 30 minutes and burn for 40 minutes.

The fire continues to decrease, indicating that corn straw pellets release more heat when burning than pine and poplar pellets;

At the same time, the ash produced after burning corn straw pellets is more than that produced after burning pellets made of pine and poplar wood, and the more ash produced can be made into high-quality fertilizer after optimized treatment.

Therefore, from this aspect, corn straw pellets are better than pine and poplar pellets.

But it must be clear that wood pellets have particular natural and market advantages. Which type of pellet processing business to develop ultimately requires a comprehensive analysis of raw material channels, raw material prices, pellet prices, market prospects and other factors. （Maybe you are interested in our wood pellet mill）

When the initial state is at safe moisture and a certain density, biomass pellet fuel can be safely stored for a long time regardless of the storage method.

At present, most biomass pellet fuels are stored in bags and accumulated in warehouses. Ventilation should be paid attention to during the storage process. In addition, there are also forms such as piles and silos.

In terms of durability, the best resistance to breakage is when corn pellets are stored in the open air, and the worst is when wood pellets are stored in the open air.

With the naked eye, straw pellet fuel has more surface cracks than wood pellet fuel, and the surface is rough and easy to break. Wood pellets are stronger and not easy to break.

The crack spacing of biomass pellet fuel made from corn straw material is larger than that of biomass pellet fuel made from wood chips, and the crack gaps are wider.

Therefore, straw pellets are easier to break than wood pellets. However, this is a problem that can be improved by adjusting the particle processing process.

The straw pellet fuel is in the shape of irregular scales, while the wood pellet fuel is layered with a convex center, and the granules are bent to both sides. The reason is that the particle size distribution of the wood pellets is more uniform than that of the crushed straw granules, with more than 80% granules with particle size less than 1mm, and the granules after compression molding are arranged more neatly.

Judging from the current situation of raw material crushing particle size, when the pressure is the same, the particle density of straw pellet fuel is slightly worse. If the density of straw pellet fuel is increased, the pressure required for straw will be greater than that of wood chips.

In the production process of using straw to produce biomass pellet fuel, fine powder should be carried out after the straw is coarsely pulverized to make the straw powder particle size smaller and make the particle size distribution more uniform, which can improve the molding quality of biomass pellet fuel, but the cost increases accordingly.

Using corn straw as raw material to prepare pellet fuel, adding 3% MgCO³, CaCO³, and Al²O³ additives can effectively resist slagging. Among them, adding 3% MgCO₃ has the best anti-slagging effect, and the slagging rate is basically zero; adding 3% CaCO₃ additive has a slagging rate lower than 2.25%, and the anti-slagging effect is significant. Adding 3% Al₂O₃ has a slagging rate The rate is 11.56%, and the anti-slagging effect is good.

Cost analysis and application prospects:

• When considering the large-scale promotion of anti-slagging additives, the cost of addition needs to be considered. According to the current average market price, an addition ratio of 3% can be obtained based on economic comparison. From high to low, MgCO₃>Al2O₃>CaCO₃. The lowest cost increase per ton of corn straw pellet fuel additives is CaCO₃, but its anti-slagging effect is slightly worse than MgCO₃;
• Although MgCO₃ has the best anti-slagging effect, its cost is too high and is not suitable for large-scale production and application. Therefore, the most cost-effective additive to resist slagging is CaCO₃.

Additives are added to straw pellet fuel to reduce the slagging of the fuel during combustion in the boiler, or the ash to become loose and brittle. This makes the ash easy to clean, thereby achieving the purpose of improving heat transfer efficiency and saving energy.

The use of anti-slagging additives does not affect the characteristics of the molded fuel, does not affect the normal operation of the boiler, does not change the main operating parameters, and does not cause corrosion and other hazards to the equipment. There is a large gap in the development market and broad application prospects.