Method for preparing paper pulp from mushroom residues as well as product and application thereof

Abstract

The invention discloses a method for preparing paper pulp from mushroom residues as well as a product and application thereof. The method comprises the following steps: mixing crushed mushroom residues with water, uniformly stirring, and carrying out ultrasonic treatment, screening and dehydration to obtain the paper pulp. According to the method, the fibers are separated under the room temperature condition through the ultrasonic technology, the step of high-temperature cooking is completely omitted, and energy consumption is reduced from the source. Meanwhile, no complex chemical reagent is needed in the process, so that the emission of wastewater and waste gas is greatly reduced, and the targets of low carbon and environmental protection are really achieved. According to the method, the mushroom residues are subjected to fiber separation through the ultrasonic technology, useful fiber components in the waste are fully extracted and efficiently converted into the paper pulp raw material, the additional value of the mushroom residues is increased, the negative influence of waste accumulation on the environment is reduced, and a feasible solution is provided for resource utilization of agricultural waste. And efficient separation of mushroom residue fibers is realized through an ultrasonic technology.

Description

Technical Field

[0001] The invention relates to a method for preparing paper pulp by utilizing mushroom residues, a product and an application thereof, and belongs to the field of mushroom residues. Background Art

[0002] The mushroom industry is an important part of my country's agricultural economy. It has developed rapidly in recent years, and the output and consumption of edible mushrooms have increased year by year. With the expansion of the mushroom industry, a large amount of mushroom residue is discarded as a by-product. Mushroom residue mainly comes from mushroom sticks, and its raw materials usually include corn cobs, bran, cottonseed hulls and soybean powder. These raw materials are used as the growth medium of mushrooms after mechanical crushing and granulation.

[0003] During the growth of mushrooms, the mushroom residue undergoes a process of microbial fermentation and biochemical degradation. The metabolic activities of microorganisms and the cold and humid culture environment cause the cellulose and hemicellulose parts of the mushroom residue to decompose to a certain extent, making its fiber structure softer and easier to handle.

[0004] However, the current treatment methods of mushroom residue in my country are relatively backward, and a large amount of mushroom residue is piled up or discarded without effective utilization, resulting in resource waste and environmental pollution. On the one hand, the large amount of mushroom residue piled up will occupy land resources and cause environmental pollution due to the release of gas during the fermentation process; on the other hand, mushroom residue is still rich in usable components such as cellulose. If it can be used scientifically, its economic and environmental value will be significantly improved.

[0005] Pulp production is the core of the paper industry. Traditional pulp production mainly relies on wood as raw material. This dependence has led to a large amount of deforestation, which has had a serious negative impact on the ecological environment. According to statistics, the area of ​​forest cut down for pulp production worldwide is about 150 million hectares each year, which is equivalent to the disappearance of a football field-sized forest every minute. This large-scale deforestation not only destroys biodiversity, but also exacerbates climate change.

[0006] In addition, the traditional pulp manufacturing process usually requires high-temperature cooking and a large amount of chemical treatment to decompose lignin and cellulose, which not only consumes a lot of energy, but also produces a large amount of wastewater and harmful gases, causing further pollution to the environment. Data shows that the pulp and paper industry is the fifth largest source of greenhouse gas emissions in the world, emitting about 200 million tons of greenhouse gases equivalent to carbon dioxide each year. At the same time, the wastewater generated in the pulp production process contains a large amount of organic matter and chemicals. If it is not properly treated and discharged, it will cause serious damage to the aquatic ecosystem.

[0007] In order to solve these problems, in recent years, the pulp production industry has begun to explore the use of non-wood fiber raw materials, such as agricultural waste, waste paper, etc., as alternative raw materials to make pulp. These materials are usually rich in cellulose, but compared with traditional wood, their processing and utilization face different technical challenges. For example, the composition of agricultural waste is complex and contains more non-fiber components, requiring specific pretreatment and processing technologies to effectively separate the usable fibers. Studies have shown that the use of agricultural waste to produce pulp can reduce energy consumption by about 20% and water pollution by 30%.

[0008] Therefore, developing a new method for making pulp from mushroom residues at room temperature can not only reduce energy consumption, but also alleviate the problem of mushroom residue waste, providing important support for my country's circular economy and green agriculture. Summary of the invention

[0009] Purpose of the invention: The technical problem to be solved by the present invention is to provide a method for preparing pulp using mushroom residues and its products and applications.

[0010] Technical solution: To solve the above technical problems, the present invention provides a method for preparing paper pulp using mushroom residues, comprising the following steps: mixing the crushed mushroom residues with water, stirring evenly, performing ultrasound, screening, and dehydrating to obtain the paper pulp.

[0011] Wherein, the mass ratio of the crushed mushroom residue to water is 1:4-1:5.

[0012] The purpose of using a stirrer to stir the mixture at room temperature until it is completely uniform is to avoid damage to the fiber structure caused by high temperature, to initially disperse and dissolve the fibers, and to reduce adhesion.

[0013] The frequency of the ultrasound is 25-40 kHz, the duration of the ultrasound is 8-30 minutes, and the ultrasound power is 500 W. The specific frequency and power of the equipment can be adjusted according to the viscosity of the suspension, the fiber concentration and the target fiber length.

[0014] Preferably, the frequency is initially set to 30kHz, which can effectively penetrate the mushroom residue suspension and is sufficient to produce sufficient mechanical action and cavitation effect without causing excessive damage to the fibers. The recommended power is initially set to 500W, and ultrasonic treatment under this parameter can maximize the fiber separation efficiency while maintaining the integrity of the fibers.

[0015] The recommended initial treatment time is 25 minutes, which is optimized based on experimental data and is sufficient to achieve the best fiber separation effect.

[0016] Under the action of ultrasonic equipment, cavitation effect and acoustic streaming effect will occur inside the liquid. The cavitation effect is caused by the rapid generation and rupture of microbubbles formed during the propagation of ultrasonic waves. This rupture will produce local high temperature and high pressure around the fiber, thereby destroying the adhesion of the fiber and dispersing it into independent fiber units.

[0017] The acoustic streaming effect promotes the directional movement and layer separation of fibers, allowing fibers with different physical properties to be layered in an orderly manner, avoiding fiber breakage or mixing problems that may occur in mechanical separation.

[0018] Compared with traditional centrifugal equipment, ultrasonic processing does not require complex mechanical structure. Only by adjusting the frequency and power of the ultrasonic equipment, fine control of fiber length and uniformity can be achieved, thereby obtaining fiber pulp suitable for specific papermaking needs.

[0019] Data shows that after using ultrasonic technology, the fiber separation rate is increased to more than 95%, and the energy consumption is reduced by about 30% compared with the traditional centrifugal method. At the same time, the integrity and uniformity of the pulp fiber are improved by 20%.

[0020] Ultrasonic equipment can make the fiber separation length more uniform, and the fiber length is concentrated in the range of 0.7-2mm, which is suitable for the requirements of papermaking process; ultrasonic treatment does not require chemical additives, reducing chemical pollution; ultrasonic equipment occupies a small area, has a simple structure, and has low maintenance costs, and is suitable for promotion and application in small and medium-sized factories.

[0021] The diameter of the screen is 0.1-0.5 mm, which further separates fine particles to obtain fiber slurry with uniform length.

[0022] Wherein, the dehydration temperature range is 20-60°C.

[0023] Among them, the mushroom residue comes from the mushroom sticks, and its raw materials are corn cobs, bran, cottonseed hulls and soybean powder. After mechanical crushing and granulation, it is used for the growth of mushrooms.

[0024] The growth cycle of mushrooms is three to four months. During this period, microorganisms and the humid and cold environment further ferment the matrix of the mushroom residue, causing the fiber part to decompose and soften.

[0025] After harvesting the mushrooms, the mushroom residue is simply physically crushed. A small amount of old mushroom skin may be mixed in during this process, but since there is no soil or fertilizer in the mushroom residue, it does not need to be cleaned.

[0026] The present invention further separates the fibers in the mushroom residue through a unique ultrasonic treatment technology, thereby realizing efficient preparation of paper pulp. The method of the present invention does not require high-temperature cooking, is energy-saving and environmentally friendly, and improves the utilization value of the mushroom residue. Compared with traditional centrifugal equipment, this method omits additional mechanical treatment steps, reduces equipment energy consumption, and protects the integrity of the fibers.

[0027] The invention also provides pulp prepared by the method.

[0028] Wherein, the fiber length of the pulp is 720.25-3120.36 μm.

[0029] The invention also provides application of the pulp in preparing paper.

[0030] In the process of preparing pulp by traditional cooking process, high temperature or too long time will lead to fiber collapse (fiber over-degradation or pulp quality reduction), while the mushroom residue involved in the present invention does not need to be cleaned and sorted before pretreatment and is clean in itself.

[0031] Traditional cooking methods need to be carried out under high temperature and high pressure conditions, which requires a large amount of steam and chemicals, resulting in high energy and material consumption. A large amount of waste liquid (such as black liquor) is generated during the cooking process, which contains high concentrations of organic matter and chemicals. It is difficult to treat and will cause serious environmental pollution if not handled properly. In addition, foul-smelling gases may be produced during the cooking process, further polluting the atmosphere. The pulp yield and quality are limited, and the yield is low: cellulose and hemicellulose will degrade during the cooking process, resulting in a decrease in pulp yield.

[0032] Strength problem: If the pulp is overcooked, the cellulose will be over-degraded, resulting in a decrease in pulp strength. Color problem: The pulp after cooking is darker in color, especially the pulp cooked by the kraft process, which is more difficult to bleach.

[0033] Uneven cooking: Traditional cooking equipment (such as vertical cooking pots) may cause uneven heating of mushroom residue, which in turn affects the stability of pulp quality. Continuous cooking equipment has a complex structure, many auxiliary equipment, high manufacturing requirements, and high investment costs. Insufficient production flexibility. Once the equipment fails, the entire production line will stop working, which has a great impact.

[0034] Fiber damage risk: During the cooking process, if the temperature and time are not properly controlled, it may cause excessive fiber degradation or damage, affecting the final performance of the pulp. Although the cooking method for preparing pulp is widely used in the papermaking industry, its high energy consumption, high pollution, and limited pulp quality have not yet been solved.

[0035] Beneficial effects: Compared with the prior art, the present invention has the following significant advantages:

[0036] 1. The present invention uses ultrasonic technology to separate fibers at room temperature, completely eliminating the high-temperature cooking step, reducing energy consumption from the source. At the same time, since no complex chemical reagents are required in the process, the emission of wastewater and waste gas is greatly reduced, truly achieving the goal of low-carbon and environmental protection.

[0037] 2. Mushroom residue is an important component of agricultural waste in my country. Its main components are rich in cellulose, hemicellulose and lignin, and have high utilization value. However, due to the complex texture of mushroom residue and the high difficulty in fiber extraction, traditional utilization methods are limited to composting or simple feed processing. The present invention uses ultrasonic technology to separate fibers from mushroom residue, fully extracts useful fiber components in the waste and efficiently converts them into pulp raw materials, which not only increases the added value of mushroom residue, but also reduces the negative impact of waste accumulation on the environment, providing a feasible solution for the resource utilization of agricultural waste.

[0038] 3. The present invention realizes efficient separation of mushroom residue fibers through ultrasonic technology. This method is simple to operate and does not require the use of complex devices such as centrifugal equipment. It can ensure separation efficiency and pulp quality by simply adjusting the frequency (25-40kHz) and power (200-600W) of ultrasonic waves, reducing energy consumption and equipment maintenance costs. In addition, this technology can also protect the integrity of the fibers, avoid fiber damage caused by mechanical separation, and ultimately produce high-quality pulp with uniform length and stable structure to meet the actual needs of industrial papermaking. DETAILED DESCRIPTION

[0039] The technical solution of the present invention is further described below.

[0040] The mushroom residue left after the mushroom production of Jiangsu Hongfeng Fruit and Vegetable Food Co., Ltd. was collected. The main components of the mushroom residue include a mixed matrix of corn cobs, bran, cottonseed hulls and soybean powder, which has been mechanically crushed and granulated before being made. Among them, after three to four months of growth of mushrooms, the texture of the mushroom residue has been significantly softened, and its internal fibers have been partially decomposed by microorganisms, making it easier to handle as a whole. Since there is no soil and fertilizer in the mushroom residue, there is no need to wash it.

[0041] Mix the collected mushroom residue with deionized water in a mass ratio of 1:4, place in a stirring device and stir evenly to disperse the fibers initially and form a suspension. The stirring time is controlled within 30 minutes to ensure that all fibers are completely soaked.

[0042] The suspension was treated with ultrasonic equipment. The specific equipment parameters were set as follows: ultrasonic frequency 30kHz, power 400W, and treatment time 25 minutes. Under the action of ultrasound, strong cavitation effect and acoustic streaming effect were generated inside the liquid. The cavitation effect generates a high temperature and high pressure environment locally through the formation and rapid rupture of tiny bubbles, effectively destroying the binding force between fibers and dispersing them into separate fiber units; the acoustic streaming effect promotes the stratification and directional arrangement of fibers in the suspension, thereby improving the separation efficiency and optimizing the fiber quality.

[0043] After the treatment, the larger particles and undispersed residues are removed by sieve filtration to obtain a fiber slurry with uniform length.

[0044] The separated pulp is dehydrated. Most of the water is removed by vacuum filtration at room temperature, and then placed in a drying oven for natural drying at room temperature or further dehydration by low-temperature drying (below 50°C), ultimately producing a pulp product with good uniformity and appropriate fiber length.

[0045] Performance and characteristics of pulp: fine and uniform fibers, relatively uniform stress distribution, moderate fiber length and aspect ratio, and good interweaving ability. Fiber length is 720.25-3120.36μm, average length is 1326.58μm, and aspect ratio is 41.18. Single fiber strength is high, paper has good toughness and high elongation. High cellulose content, low hemicellulose content and lignin content, easy to cook and bleach.

Claims

1. A method for preparing pulp using mushroom residues, characterized in that: The following steps are involved: The crushed mushroom residues are mixed with water, stirred evenly, ultrasonicated, sieved and dried to obtain the paper pulp.

2. The method according to claim 1, characterized in that: The mass ratio of the crushed mushroom residue to water is 1:4-1:

5.

3. The method according to claim 1, characterized in that: The frequency of the ultrasound is 25-40 kHz; the time of the ultrasound is 8-30 minutes.

4. The method according to claim 1, characterized in that: The diameter of the screen is 0.1-0.5 mm.

5. The method according to claim 1, characterized in that: The drying temperature ranges from 20 to 60°C.

6. A pulp prepared by the method according to any one of claims 1 to 5.

7. The pulp according to claim 6, characterized in that: The fiber length of the pulp is 720.25-3120.36 μm.

8. Use of the pulp according to any one of claims 6 to 7 in the preparation of paper.