[Daily Question 20090318] Discussion question on turning crop straw into treasure

Various crop straws can be used as feed, paper-making raw materials, base materials for growing edible fungi, raw materials for biogas digesters, etc. The wastes are returned to the fields, which not only protects the environment but also saves fertilizers and increases efficiency. And now there is a straw juicer. The juice squeezed from corn straw can be used to produce fuel ethanol, natural chlorophyll and xylitol. The fuel rods produced can be further carbonized and processed into carbon rods, which can replace part of coal as fuel for urban heating and power plants. This post was last edited by zcj41000 on 2009-3-18 07:39 ]

Content comes from: http://bbs.hcbbs.com/thread-118923-1-1.html Straw is the general name for the stems and leaves (ears) of mature crops. Usually refers to the remaining part of wheat, rice, corn, potatoes, oilseeds, cotton, sugarcane and other crops after harvesting the seeds. More than half of the products of crop photosynthesis exist in straw. Straw is rich in nitrogen, phosphorus, potassium, calcium, magnesium and organic matter. It is a multi-purpose renewable biological resource and is also a roughage. It is characterized by high crude fiber content (30%-40%) and contains lignin, etc. Although lignin cannot be utilized by pigs and chickens, it can be absorbed and utilized by ruminant cattle, sheep and other livestock. Straw building materials Straw is an efficient and long-term raw material for light industry, textile and building materials. It can not only partially replace bricks, wood and other materials, but also effectively protect cultivated land and forest resources. The thermal insulation, decoration and durability of straw wall panels are all excellent, and many developed * * "Straw boards" have been widely used in the construction industry as an alternative to wooden boards and ceramic tiles. In addition, after processing straw through technical methods, it can also produce rayon and artificial cotton, produce furfural, maltose, wine and xylitol, process fiberboard, etc. The Renewable Clean Energy Laboratory of the University of Science and Technology of China announced that a latest scientific and technological achievement developed by Professors Zhu Xifeng, Guo Qingxiang and others can fundamentally solve this long-standing problem. They pyrolyzed, liquefied and reprocessed a variety of raw materials such as sawdust, rice husks, corn stalks and cotton stalks, turning waste into treasure and converting them into bio-oil. The oil production rate of wood chips was more than 60%, the oil production rate of straw was more than 50%, and the calorific value of bio-oil was 16 to 18 megajoules/kg. This achievement has passed pilot trials, and industrialization is just around the corner. According to reports, my country produces more than 700 million tons of crop straws and agricultural product husks every year. Burning them on site not only wastes resources, but also causes serious environmental pollution. Using this technology, biomass such as straw can be directly converted into bio-oil, which can be directly burned and used as fuel in oil-fired boilers and industrial kilns. After refining and refining, it can be used as vehicle fuel, and high value-added chemical products can also be separated and extracted. Experts from the University of Science and Technology of China proposed the best route for industrialization of this technology based on years of research experience.: First, biomass is dispersed and pyrolyzed on a moderate scale at the source of raw materials and converted into bio-oil, a primary liquid fuel that is easy to transport and store. Then the bio-oil obtained from pyrolysis in various places is collected and reprocessed. This can fundamentally solve the bottleneck problems of large-scale application such as dispersed biomass resources and seasonal restrictions. According to reports, the optimal scale of a single pyrolysis and liquefaction machine is to process 2 tons of straw per hour (the straw collection radius is about 10 kilometers), produce 1 ton of bio-oil, and the production cost is about 790 yuan/ton. After simple quality improvement, the calorific value of bio-oil increases to about 18-20 MJ/kg, and the sales price is assumed to be 1,000 yuan/ton. When it is used to replace diesel and heavy oil, it provides the same heat, and the price is equivalent to 43.2% and 63.1% of the current prices of diesel and heavy oil respectively. The current mature gasifier technology has been promoted.

Paper can be made from tangerine stalks, but paper mills using tangerine stalks as raw materials cause serious pollution and are difficult to control. Orange stem gasifier, I heard is good. I have never seen it, and I don’t know whether it is economically and technically feasible. The orange stalks can be returned to the fields. Seriously opposed to orange pole burning!

Burning straw is a bit wasteful and pollutes the environment, especially for flying. Currently, straw is generally used for processing into feed, artificial boards, activated carbon, and cultivating edible fungi. It is also used to make paper. However, because the straw fiber is short and contains many impurities, the quality of the paper is not high, and it is not enough to make some cardboard, corrugated paper, superstitious paper, etc. http://bbs.hcbbs.com/thread-404911-1-1.html

Straw can be fermented to produce alcohol, which not only does not cause pollution, but also produces certain economic benefits.； It can also be used as a raw material for manufacturing furfural.

Straw papermaking causes high pollution, poor paper quality, difficult processing of papermaking black liquor, and high operating costs. It is simply uneconomical from an economic perspective if pulping does not reach a certain scale. There are also straw power generation companies (there are probably more than 30 in Henan Province), but the supply and storage of raw materials is a big problem. Some power generation companies have to burn part of the coal to replace the straw to maintain operation. The production of biodiesel and ethanol from straw all have problems with the supply of raw materials and pollution control. In fact, returning straw to fields is a better way, but without good organization, the masses are afraid to be interested in it. One of the tasks of the Environmental Protection Agency now is to supervise the burning of straw. You can check out the website of the Ministry of Environmental Protection. Satellites are used to supervise environmental protection departments in various places. In short, there is currently no practical way to utilize straw. The effective utilization of straw still has a long way to go.

Recommended biochemical treatment: Anaerobic fermentation produces biogas, which is relatively strong in seasons. It can be adjusted with livestock manure and organic waste to stabilize the amount of biogas. Biogas can be used for civilian use, as fuel for other facilities, or for power generation.

Agree with the person above, some waste straw cannot be used for paper making, etc. Especially in rural areas, there are still a lot of such resources. Biogas digesters are a good choice, but at present, biogas digesters have not been popularized due to economic, technical and its own shortcomings. I believe that with the advancement of technology, * * With policy support for this industry, biogas digesters can play their due role.

us* * We are not advocating biomass power generation now, but it is a pity to burn it directly. It would be great if it can be processed and utilized in multiple stages before burning!

Various crop straws can be used as feed, paper-making raw materials, base materials for growing edible fungi, raw materials for biogas digesters, straw retort, etc. The wastes are returned to the fields, which not only protects the environment but also saves fertilizers and increases benefits. And now there is a straw juicer. The juice squeezed from corn straw can be used to produce fuel ethanol, natural chlorophyll and xylitol. The fuel rods produced can be further carbonized and processed into carbon rods, which can replace part of coal as fuel for urban heating and power plants. We firmly oppose the practice of directly burning orange stalks and returning them to the fields.

Paper can be made from tangerine stalks, but paper mills using tangerine stalks as raw materials cause serious pollution and are difficult to control. Orange stem gasifier, I heard is good. I have never seen it, and I don’t know whether it is economically and technically feasible. The orange stalks can be returned to the fields. Strong opposition to tangerine pole burning

Straw is a biomass raw material that can be gasified to generate syngas, which can further generate liquid fuel. Some units, such as the Shandong Academy of Sciences, have been engaged in this technology for many years.: http://www.sdas.org/index.do

The above people have explained in detail how to utilize straw.: As a personal opinion, the most important thing is to promote the value of straw to the farmers, the producers of straw, and let them know that straw is also a kind of harvest. We have many ways to turn straw into treasure, but most of the straw is still burned or disposed of immediately after harvesting.

The Ministry of Agriculture mainly promotes orange stem gasifiers. The key issue at present is the collection cost. Henan and other places are major food provinces, and it is cost-effective to establish biomass (biodiesel) processing plants. For scattered areas, how to solve the problem of collection is a problem.

There are currently two major applications, one is to process it into feed and raise livestock, and the other is to use it for fermentation, making alcohol, and making fuel! :lol

The main uses of biomass include gasification or pyrolysis, forming solid fuel, liquefaction, and biogas production. I used to study the gasification and combustion of substances. Gasification can produce high-quality gas or synthetic gas. ； Combustion can partially replace coal as fuel, be used in industries such as ceramics, or be used to generate electricity. There are already many biomass power plants in China. * * There are policies to subsidize electricity prices. Liquefaction does not seem to be very mature yet. Due to the low energy density of biomass, collection and transportation costs are relatively high.

Other uses of straw http://bbs.hcbbs.com/thread-118923-1-1.html I posted this before. From my personal opinion, I am afraid that fermentation to produce alcohol may be the mainstream method of use in the future.

Straw “commercial grass” drives chain economic straw utilization: Through the cutting and kneading process, the hard stalks on the surface of the straw are destroyed, which improves the digestion and absorption of livestock and poultry. The length of the extruded forage is 10-20 cm, the diameter is 1-2 mm, and the texture is soft. The part of the straw that the livestock and poultry cannot eat directly is processed into a feed with good palatability, and the original nutrients and moisture of the straw are completely retained. ； Through biological fermentation technology, the lignin and cellulose of the straw are degraded into oligosaccharides, lactic acid and volatile fatty acids ； Through microbial reproduction, the protein content of straw bacteria is increased and the nutrients of straw are increased. ； By adopting bag fermentation technology, the waste of straw forage during storage and use is greatly reduced. Generally, silage corn straw is stored in a cellar. Due to the opening of the cellar to collect materials, air can easily enter the cellar, causing a large amount of mildew, and the waste rate of silage straw reaches 20%. The use of bag storage can not only facilitate the sealing of materials after retrieval, so as to avoid mildew, but also uses small packaging, usually 75 kilograms of material per bag, and feeding can be completed quickly, reducing the chance of mildew, which is very suitable for our current small-scale breeding level. The second lightweight wallboard of Zhifu Project turns straw into treasure and uses it: After crushing wheat, corn and other crop straws, using their plant fibers, and adding water and chemical raw materials, we can produce high-strength building wall panels for frame buildings, weighing only about 35 kilograms per square meter. This product has been listed * * Spark Technology Promotion Project. Zhifu Project Three Baler Recycles Straw to Create Maximum Profit Straw Utilization: The straw baler can work on wheat straw, bean straw, rice straw, cotton straw, corn straw, reed straw, etc. without replacing any other devices. It is not restricted by region and time. As long as there are conditions and where there is straw that needs to be bundled, the baling operation can be completed smoothly. After that, the "finished products" are sent directly to paper making, power generation and breeding plants that need the raw materials to obtain profits. The fourth straw fermentation of the Zhiwei Project turns field “waste” into ethanol and utilizes straw: The first stage of straw fermentation and utilization technology is to use bacterial microorganisms to convert grain and straw into glucose. The products produced are used as food and feed additives, which is the second stage of grain and straw utilization. The third stage is to make it into a degradable, pollution-free plastic organic film, and then form a mature industrial chain. Wealth Project: Wheat Straw Retting and Fertilization Returned to Fields to Help Farmers Save Money on Fertilizer and Utilize Straw: Select a field edge or an open space near a village with flat terrain and close to water sources, pound the ground firmly, and spread a layer of wheat bran. Then spread a layer of short and water-soaked straw and weeds evenly to a thickness of about 25 cm. After compacting, pour human feces and livestock feces. If there is insufficient human and animal manure, urea can be added at 0.5% of the dry straw weight and superphosphate can be added at 2%. Spread a layer of 10 cm thick pond mud or pen fertilizer such as pig tread mud on top, and then spread straw on top. Stack them layer by layer in this way until they are 1.5-2 meters high. Finally, apply some thin mud. Turn the pile over in about 30 days, add water and pile it again. It can be accumulated into high-quality organic fertilizer in 2 months in summer and 3-4 months in winter. The six-straw power generation project of Zhifu Project increases income by 125 yuan per mu of land. Straw utilization: The straw power generation project can turn crop straw into treasure. According to calculations, the power generation capacity of every two tons of straw is equivalent to one ton of coal. After straw is fully burned, it can not only reduce pollution and protect the ecological environment, but also the bottom ash and charcoal ash after burning straw are organic fertilizers rich in various trace elements, which can be directly applied to farmland to increase soil fertilizer efficiency. At the same time, farmers can increase their income by selling straw. Get rich project 7 "Straw imitation solid wood door" to increase environmental benefits and use of straw: It mainly uses straw and several cheap and abundant common chemical materials as raw materials, so the raw material cost and labor cost are low. Moreover, the raw materials are sufficient and widely available, easy to collect, the production technology is advanced, and energy is saved. In addition, the production process of this product is formed in one step, without the need for planing, sawing, nailing, gluing, and no need for assembly. The process is simple and the production efficiency is high. ； It has its own wood grain after being taken out of the mold, and can be imitated from various precious tree species. The surface treatment of the product is simple, and the surface treatment can be directly painted. The texture is as elegant and natural as a wooden door, with realistic and diverse textures. It can also be covered with PVC decorative film with various methods. The Eighth Wealth Project "Straw Ecological Board" aims to utilize straw, a cheap biological resource: “"Straw ecological board" uses straw instead of wood to produce composite boards. At present, my country's wood resources are scarce and more than 500 million tons of straw are produced every year. Most of them are burned, causing waste of resources and environmental pollution. Project No. 9 for getting rich: What you eat is "grass" and what you spit out is "straw gas". Straw utilization: The straw gas production device uses a large amount of cheap straw in rural areas as raw material to produce gas. After straw gas production begins, the gas enters the gas furnace, goes through processes such as smoke filtration, sulfur removal, and purification, then enters the gas cabinet, then enters the pipe network, and finally enters the user. The gas supplied to rural households is similar to liquefied gas. Under the same usage conditions, in addition to being more environmentally friendly than coal gas, the cost is half that of ordinary liquefied gas tanks. According to calculations, 1.5 kilograms of straw can produce 1 cubic meter of straw gas. Get rich project 10 "Straw Home" makes your home more beautiful using straw: Straw weaving is a traditional folk craft. In ancient times, working people used straw to make hats for sun protection and straw shoes for foot protection after farming. As time went by, the skills became more and more mature, and the finished products gradually changed from pure practicality to practical appreciation. Modern straw weaving uses grass, corn husks, and wheat straw produced in various places as raw materials, and uses local materials to weave into various ornaments, gifts, and daily necessities, forming a unique industrial scale. source: network

At present, using straw to produce biodiesel is the most effective resource utilization, but it will take a certain amount of time and technical strength to be widely promoted.

Or is it because my knowledge is narrow? I only know: It can be burned, broken to make feed, and can be used to make handicrafts. Thanks to the moderator, I learned a lot from Haiyou’s posts. * Got it