Our country is making rapid progress in the utilization of biomass energy. Among them, crop straws are wealth when used well, but they become garbage and disaster when not used properly. Here I would like to discuss, communicate and share with you the modes and equipment of crop straw collection, storage and transportation.

1. Crop straw situation in my country

my country’s biomass resources are relatively extensive, and there are a large number of unused resources in forests, grasslands, and cultivated fields. The residual branches under trees and shrubs (including caragana, black locust, bamboo willow, etc.) in forest areas; grassland resources are more abundant than the amount of crop straw in arable land; according to statistics, my country's annual crop straw output is 700 million tons, accounting for 10% of the world's straw. The annual output is 24% of 2.9 billion tons, ranking first in the world, equivalent to 353 million tons of standard coal. Among them, straws from food crops such as rice, wheat, soybeans, corn, and potatoes account for 89% of the total, straws from oil crops such as peanuts, rapeseed, sesame, and sunflower account for 8% of the total, and cotton and sugarcane straws account for 3% of the total. %.

? The meaning of straw. Straw should refer to crop stems with a moisture content below 30%. Those with a moisture content between 30-67% should be collectively called yellow storage, and those with a moisture content above 67% are called silage. If they are lumped together, there will be a big gap in the estimation of the total amount of straw, which will lead to errors in policy formulation.

For example: Heilongjiang currently has 220 million acres of cultivated land, which can produce 137 million tons of straw based on the current grain-to-grass ratio. But in fact, there are nearly 100 million acres of corn cultivation in Heilongjiang, with an average yield of 650 kilograms per mu (666.67 square meters per mu). The actual collected corn straw is only 400 kilograms per mu, and the ratio to seeds is 1:0.65, which is far from Lower than the standard calculation of 1:1.86. The reason for the difference is that the moisture content of the stalks when harvesting corn is generally around 55%. Furthermore, the root stubble is not recyclable, so the difference is huge.

Generally, the straw of food crops with a moisture content greater than 30% will quickly burn and rot. Judging from the current collection situation, the harvestable straw yield per acre is: 400 kilograms of corn straw, 200 kilograms of wheat straw, and 200 kilograms of rice straw. 300 kg, soybean straw 250 kg. my country's grain output is 660 million tons, and straw output is also 600-700 million tons. The total recyclable amount is 1:1.

Straw utilization rate. The utilization rate of straw is not as high as 80% as reported by various places. It is roughly estimated that my country is currently directly returning it to fields as fertilizer (15%), as feed (15%), and for new energy sources such as power generation and gasification (4 %), as building materials and other industrial raw materials (1%), as base material for edible fungi (1%), firewood (10%), waste or open burning (56%), this set of data is quite credible, and That is to say, at least 50-60% (more than 400 million tons) of straw is wasted in our country every year.

The reason is that in addition to the fact that there are not many ways to comprehensively utilize straw in our country, the insufficient straw collection capacity is the bottleneck of the entire industry, which is far from being able to return the particles to the warehouse like collecting grain.

2. Current status of straw collection

At present, the main driving force for straw disposal is environmental protection and the ban on burning. The agricultural department is in charge of the work, advocating that straw processing be mainly for agricultural use, and vigorously returning it to the fields. Then other uses of the straw will be made. There are two main methods of straw disposal: "returning to the field" and "leaving the field".

Return straw to fields. Since returning straw to fields is quick and easy to implement, it has been favored by local governments. However, there are still some problems in returning fields that have not been well solved. A large amount of straw is mixed on the surface of the soil, resulting in loose soil, reduced bulk density, and structural deterioration, forming "straw soil." "Straw soil" provides a "breeding ground" for pests and diseases, increasing the incidence of pests; affecting seed germination and rooting; causing the phenomenon of "hanging roots", affecting early crop growth; poor drought resistance and lodging resistance; high straw carbon-nitrogen ratio, and straw rot During solution, they compete with seedlings for nitrogen sources. In the north, the long winter cannot meet the two basic conditions of temperature and humidity for straw to mature. Neither mulching nor returning to the field with ginseng can raise the temperature. The humidity is also difficult to reach 60%, and the conditions for straw to mature are not met. Therefore, even if straw is returned to the field, it should be collected and processed, and then returned to the field through belly return, retting, carbonization, etc. Methods such as returning the straw in full or directly to the field will cause agricultural harm.

Agricultural reclamation companies have large agricultural machinery that can plow 35 centimeters deep to return the fields, but local agriculture does not have this capability, so it is not appropriate to return the fields directly.

Straw leaves the field. Mainly the bundled collection mode.

1. Hammer-type picker baling machine uses a hammer and a rotary knife to rotate at a high speed of more than 2,000 rpm to break the stalks on the ground and use negative pressure to pick up the broken stalks. This method does not require a rake to collect strips, and the picking up is relatively clean and can deal with root stubble on the ground. However, it consumes high energy and has low picking efficiency. Generally, it can only pick up 1-2 tons per hour, and a single machine can only collect about 30 acres per day. , cannot carry out large-scale operations and is only suitable for collecting feed in small pastures.

2. The spring-tine pick-up efficiency is high. When used with a rake, it can pick up about 30 acres per hour. The general operation process is: after harvesting the straw, dry it in the sun and dewater, use the rake to collect the straw, and then A baler is used to pick up and bundle the bales, and a bale trailer or straw grabber is used to remove the bales from the field, and then they are stacked in the storage yard or transported to the material unit. This model is widely used in China because of its high efficiency.

Baling machines are divided into small square bales, large garden bales, and large square bales. Small square bales are relatively inefficient and have low density. Generally, the bales weigh 20-30 kilograms and require manual picking and loading. The traction power is about 60 horsepower, which is suitable for small plots and is rarely used in the north. Large round balers are the most common, with a bundle diameter of 1.25 meters and a length of 1.2-1.5 meters. The weight of a single bundle is generally 200-300 kg. It is shaped with nets and ropes and has a power of about 130 horsepower. Generally, the price of domestically produced garden baling machines is around 180,000 yuan, while imported ones cost more than 400,000 yuan. The large square baling machine has the highest efficiency because it can operate without stopping. It is suitable for large land operations. The bale weight can reach 400 kilograms. The price of the baling machine is generally between 1.1 and 1.7 million yuan. The supporting power is more than 230 horsepower. The overall weight Reaching 17 tons, it is not suitable for repeated summer harvest operations.

At present, the country has a purchase subsidy policy, which is generally below 60%.

3. Several other collection methods: There are some different straw collection methods according to different land types and different crops.

Mountainous and hilly areas are inconvenient for straw collection equipment to enter, so manual harvesting and leaving the fields can only be used.

It is easy for vehicles to get trapped in rice fields. Some manufacturers use crawler-type equipment, and some manufacturers are transforming into self-propelled balers to reduce the turning radius and improve maneuverability.

For semi-dry yellow storage, some use a neck and ear collector, which can receive raw materials with low impurity content, but the efficiency is low. The collected materials are not easy to store because the moisture content is too high. Generally, Used for wrapping or as raw material for biogas or fertilizer production.

When collecting silage, a disc harvesting table is generally used. After crushing, it is sprayed into a trailer that receives the material and transported to the stockyard. It is also packaged, wrapped in film, and stored in a "gut" method.

This year, some farmers in the Northeast are using grass collection cages. They use forklifts and tractors to push or pull the straw into the "cage" by relying on the friction between the straw and the ground. This method requires hard dragging, which consumes a lot of energy. Moreover, the humus soil and residual snow on the ground are added to the straw pile, and the quality of the straw is very poor. After pushing a full cage, it cannot be moved anymore, and it has not been really done yet. It is not possible to work on land with ridges such as rice fields or rice fields, and it is also impossible to work if it slips in the snow.

Common problems in baler operations.

The spring-tine baler is used abroad to collect forage grass. It is OK to introduce it to China to collect wheat straw and rice straw. If it is used to collect corn straw and bean straw, the operating efficiency and damage rate are not satisfactory. Not to mention collecting cotton stalks, sunflower stalks, and whole corn stalks, especially under ridge farming in the Northeast, there are more problems.

First of all, the cost of net ropes is high and there is also pollution from net ropes.

Secondly, due to structural problems, the soil filtering effect is not good, the soil content is generally about 15%, and the quality of the raw materials is low. A certain amount of topsoil from the cultivated layer will be taken away. The soil taken away after 2 to 3 straw collections is equivalent to a year of mild soil erosion in areas such as the black soil areas of Northeast China.

Furthermore, it is necessary to pick up the bales and leave the fields twice, during which the land is repeatedly crushed.

In addition, the straw collection operation time in Northeast China is short. In winter, the equipment will slip or become sticky due to the melting of snow, making it impossible to operate normally. It only takes 5 days to operate in wheat-producing areas, so the efficiency is low.

The pick-up rate is low. In the case of ridge farming in the Northeast, there will always be 2-4 straws in the furrows that cannot be picked up cleanly, which forms the foundation of what farmers call the field and will still affect land preparation and sowing.

The equipment structure is complex and easy to be damaged. The baler has a complex structure and many moving parts. The operation in the ridge is very dusty. The traditional retainer and cam mechanism are easily damaged. Without the ability to repair, normal operation cannot be guaranteed.

3. New straw collection, storage and transportation model

In response to the appeal, it is necessary to find a straw collection method and equipment that is more suitable for my country's national conditions. A new straw collection method is introduced below.

1. The basic requirements are:

1) The collection efficiency is high, and the single-machine operation must be more than 300 acres per day (calculated in 10 hours).

2) The collection cost is low, with the collection cost per mu of land being less than 12 yuan.

3) The net collection rate is high, and the straw residue per mu is less than 8%.

4) The impurity content rate of straw is low. The impurity content (soil content) rate of straw should be less than 5%.

5) The failure rate is low, and it can work continuously for 70 hours without major failures. It is easy to maintain and does not miss the farming season.

6) It can collect various straws, including short-stem wheat and soybeans, tall-stem corn, cotton stalks, sunflower stalks, etc.

7) You can leave the field at one time without having to pick up the bales twice.

Straw collection must comply with the principle of high-density leaving the field. It is best to produce high-quality raw materials on-site in the field.

2. The following modes can be used for reference:

1) On-site granulation mode. A trailer produced by the German company Croni can collect and pellet in the field. While picking up and collecting, it uses the principle of rotary punching to press out straw pellets with pairs of rollers. The output can reach 5 tons per hour. This method is called The ultimate in straw collection. However, there is also the problem that the equipment is expensive, and straw with high moisture and impurity content cannot be formed on site. Heavy trucks collecting and pelletizing in the field consume a lot of energy.

2) Loose grass collection mode. It is more reasonable when the distance between pasture and storage yard is very close. Currently, biomass power plants such as Wuchang Niujiacheneng and Jilin Nong'an Huaneng in the Northeast region give priority to collecting bulk materials. Bulk materials have the advantages of low purchase price, easy inspection, and no need to unpack. A 17.5-meter-long trailer is compacted by a loader during loading. Each trailer can load 19 tons of loose straw, which is more than a flatbed truck that can only hold 73 large bales and weighs 16 tons. In the future, the collection and utilization of straw will be closer and closer, and the bulk materials can be directly processed and utilized after collection, especially biomass briquetting, granulation and other projects.

3) Loose grass picking + on-site baling mode. When the straw collection place is more than 10 kilometers away from the use site, the straw pick-up truck can be used to quickly transport the straw to the field, and then a mobile baler can be used to directly press high-density large square bales at the field. Generally, the weight of each bundle reaches 400 kg and the density reaches 250 kg/cubic meter, which is convenient for storage and transportation. Generally, baling machines using tethers can press more than 60 tons per day; baling machines using bagging can produce large square bales of 100 tons per day. During transportation, each 17.5-meter-long trailer can load 35 tons of straw, greatly reducing transportation costs.

Several types of loose grass picking equipment:

1. Straw collector (straw picking trailer)

1) Equipment functions. The straw collector (trailer) compartment is mainly 40 cubic meters. The straw collector consists of a picker, a trailer, and an unloading device.

Pickup: It adopts a patented product, which is characterized by a cam-less and retainer-less structure. This structure has no precedent in the world. This structure can arrange the spring teeth in a spiral shape to work smoothly and reliably; It can also be made into dense teeth, specially designed to pick up crushed straw; it can be made into a drum-type picker, which is specially designed to pick up the straw in the furrows in the north at one time.

The main advantages of the new pickup are increased pickup capacity, low failure rate, and easy maintenance. It only takes 2 minutes to replace the elastic teeth (originally at least 20 minutes).

The feeding roller is equipped with a spring shock filter device to filter mud and snow to the maximum extent. The impurity filtering function allows the straw collector (trailer) to operate in the snow. The operation time is longer in winter and can receive 5 times the straw (baler) in autumn. After freezing, it is not afraid of ground pressure and the soil content is low. , high-quality straw can be collected with high economic value.

Carriage part: It adopts rigid half-axle independent suspension and is equipped with agricultural wide tires to prevent the vehicle from sinking without pressing on the ground. It is suitable for farmland operations. The pickup can be raised by more than 60 centimeters to facilitate crossing ridges, especially Suitable for rice field straw collection. The hydraulic chain plate transmission mechanism equipped on the vehicle has a compacting effect when pushing the straw through back pressure, and it only takes 1 minute to unload the vehicle; the entire vehicle movement is controlled by PLC, and only one person is required to operate the operation.

Unloading device: A hydraulic motor is used to drive the chain plate to unload, and it only takes 1 minute to unload each vehicle.

2) Collection efficiency: The straw collector is very efficient because it does not stop or wrap around the net during operation. It can collect 120 tons of corn straw every day (calculated in 10 hours), with an operating area of ??300 acres; it can pick up one truck of straw. (40 cubic meters) in just ten minutes. When the water content is 30%, the weight is 5 tons, which is equivalent to 20 large garden bundles.

3) Collection volume, because you can work on snow in winter, a bicycle can collect 12,000 tons of straw in 100 days, which is equivalent to more than 20,000 acres of land. It is a baler (each operation is 2,000 tons in autumn, 4,000 acres), which can save a lot of equipment purchase costs.

4) Operation cost: The straw collector (trailer) collects bulk materials to the field. The fuel consumption per mu is 4-5 yuan, and the labor is 1.5 yuan/mu. If the equipment depreciation is ignored, the cost per mu is only 6-7 yuan, calculated to be less than 20 yuan per ton, which is the lowest cost of straw leaving the field. The garden baler collects straw into the field for about 70 yuan per ton.

5) Equipment price: The straw collector (trailer) is currently priced at 200,000 yuan. If it can receive government subsidies, it will be better promoted and applied. The vehicle can be used year-round as an agricultural vehicle.

6) Other advantages: There is no pollution from the net; the ground can be cleared when the vehicle passes by, eliminating the need for secondary bag picking operations, and autumn land preparation can be carried out immediately, so as not to miss the farming season. Winter work can alleviate the busy farming season.

2. Straw picking, filtering and rubbing machine. The equipment has the functions of picking up, feeding, filtering, and kneading. The picked straw is filtered and kneaded, and feed-grade straw is sprayed out. The efficiency is more than 10 tons per hour. By adjusting the fixed knife of the filter roller to reduce the impurity content of the straw, and adjusting the fixed knife of the kneading machine to adjust the fineness of kneading, it is an efficient equipment for making feed-grade raw materials.

3. Mobile hydraulic baler. It can be driven by diesel engines, motors, and tractors, and can be operated on-site. High-density square bags can be produced on-site. It is remotely operated, has a feeding bin and a pre-pressing bin, and eliminates the cutter, so that the main cylinder can press a batch at one time. The efficiency is very high; the model equipped with a bale bag can press 100 tons of straw per day.

Fixed garden baler. Large round bales can be pressed on site in the haystack, up to 120 tons per day.

Using equipment such as straw collectors, straw pick-up, filtering and kneading machines, mobile hydraulic balers, etc., a mobile factory can be formed to produce high-quality loose grass, high-density straw bales and on-site pressing in the fields. Block and granulate. This model can process crop straw efficiently, economically and with high quality on-site.

4. Development Direction

The straw collection, storage and transportation system will operate like the grain system. There will be a complete cross-regional service team and a sound broker system for straw collection. For market-oriented allocation of social resources, there is a straw resource platform and straw online banking.

Straw collection complies with the principle of high-density off-field, and in accordance with the requirements of high efficiency, low cost, complete equipment, low equipment maintenance rate, high straw quality, and high straw collection rate, new equipment and applicable Collection, storage and transportation mode. Mechanize the entire process of straw collection, storage and transportation.

To simplify the straw collection process, use a pick-up trailer to clear the ground after the vehicle passes by, and the land preparation can be carried out immediately.

Straw processing is localized and is processed on the field and on-site, including baling and briquetting (pelletizing).

Establish a complete straw collection, storage and transportation system. Due to the low density of straw and the differences in grain storage, it is necessary to set up storage yards, village-level storage points, and township-level storage centers on site, combined with the use of materials units. Planned scheduling is required.

Equipment should be at the village level, so that every village can be equipped with a set of straw recycling equipment, and every county-level area has straw processing and use enterprises.

Harbin Wanke Biomass Technology Co., Ltd.

Tel: 13351783333 (same number on WeChat)

Website: www.wktzc.com