Promotion and application of biomass molding fuel technology

At present, China's crop straw energy utilization is still in the initial stage of development, and the research and development depth of different technologies and industrialization are unbalanced. Straw solid molding fuel, straw compaction feed and other technologies are increasingly mature, and are in the pilot demonstration stage of popularization and application. Make full use of rural waste straw, turn it into waste treasure, replace coal, electricity, oil, gas as energy, or used as feed, fertilizer, edible fungus base material, is conducive to reducing straw incineration, save coal consumption, improve environmental quality, reduce pollutant emissions.

First, the material characteristics of biomass molding fuel

The density of biomass molding fuel is 700 ~ 1400 kg/m3; Ash content: 1% ~ 20%; Moisture: ≤15%; Calorific value: 3500 ~ 4500 kcal/kg, calorific value is about 0.6 ~ 0.7 times of coal, that is, 1.5 tons of biomass curing molding fuel is equivalent to 1 ton of coal. Exhaust gas emission after combustion of biomass molding fuel: zero CO2 emission; NO214 mg/cubic meter (trace), SO240 mg/cubic meter, far below the national standard, smoke less than 12 mg/cubic meter, far below the national standard. Therefore, in addition to replacing coal, oil and other fuels, biomass curing molding fuel can also reduce air pollution, in line with the current policy of energy conservation and emission reduction.

Second, straw molding technology

Straw molding refers to the technology of compressing straw into rod, block or granular fuel by solidification molding equipment under certain temperature and pressure. The basic structure of straw biomass is cellulose, hemicellulose and lignin, which can be softened at the appropriate temperature (usually 200-300). Using this feature, the dry and crushed loose biomass waste with a length of less than 50 mm and a moisture content controlled in the range of 10 ~ 25% is sent to the feed port by the feeding conveyor with compression molding machinery. Through the rotation of the spindle, drive the roller to rotate, under the conditions of ultra-high pressure (0.5-1.0), after the rotation of the roller, by the heat generated by the friction between the machinery and the biomass waste and the biomass waste each other or external heating, the cellulose and lignin are softened. The material is forced from the model hole into a block extrusion, after extrusion molding to obtain a cross-section size of 33-40 mm, length of more than 15 cm rod solid particle biofuel, and fall from the discharge port, after cooling (moisture content can not exceed 14%), bagged packaging. The particle ratio after molding is large, small volume, easy to store and transport, is a high volatile quality solid fuel, can be directly burned, its calorific value of up to 3500-4500 kcal, with flammable, less ash, low cost, can replace wood, coal, gas and other fuels. The basic production process of straw curing molding includes: straw collection, crushing, drying, mixing, molding, cooling, packaging and other procedures. The straw fuel after molding can replace wood, raw coal, fuel oil, liquefied gas, etc., and is widely used in biomass boilers, living stoves, biomass power generation, etc.

Third, the characteristics of biomass molding fuel

1, biomass fuel calorific value is large, calorific value is about 3500-4500 kcal, small size, saving storage space, easy transportation, reduce transportation costs.

2. Biomass fuel has high purity, high combustion efficiency, easy to burn out, and less residual carbon. It does not contain other impurities that do not produce heat, absolutely does not contain coal gangue, stone and other impurities that do not heat but consume heat, which will directly reduce costs for enterprises.

3, biomass fuel does not contain sulfur and phosphorus, does not corrode the boiler, can extend the service life of the boiler, the enterprise will benefit a lot. Combustion does not produce sulfur dioxide and phosphorus pentoxide, so it will not lead to acid rain, does not pollute the atmosphere, does not pollute the environment.

4, after the combustion of biomass fuel ash is very little, greatly reduce the site of stacking coal ballast, reduce the cost of ballast.

5. Biomass fuel is clean and hygienic, convenient to feed, and the ash after combustion is a high-quality organic potash fertilizer with high grade and can be recycled.

6, biomass fuel is nature's gift to us renewable energy, it is a response to the central call to create a thrifty society.

4. Innovation points in technology promotion work

1. Innovation of processing raw materials. The local agricultural wastes, such as fungus sticks discarded after the production of edible fungi in Funing District and chestnut skins discarded after the processing of chestnut in the northern mountain area, were fully utilized as raw materials for processing. The experiments of dry and wet ratio and raw material ratio were conducted for many times to finally press and form, which broadened the use ways of recycling and reuse of agricultural wastes.

2. Effectively solve the problem of agricultural waste disposal. Agricultural production of waste, piled up at will will affect the rural appearance, there are certain fire hazards, incineration will affect the environment, not treatment will affect the next year's production and life. Through the promotion of technology, effectively solve the problem of agricultural waste disposal, waste into treasure, in order to solve the problem of rural winter clean heating, explore a new way of energy saving and emission reduction, effectively improve the rural living environment.

3. It is more environmentally friendly than burning coal. The CO2 produced by the combustion of biomass curing molding fuel is absorbed by the plant growth period, and will not increase the total CO2 content in the atmosphere, which is called zero CO2 emission in the world, also known as carbon neutral. When the biomass curing molding fuel is burned, the emission of NOX (nitrogen oxides) is 1/5 of the coal, the emission of SO2 is 1/10 of the coal, the soot emission is less than 127 mg/cubic meter, the combustion rate is more than 11% faster than the coal, the combustion is full, the black smoke is less, the ash is low, and the emission concentration of atmospheric pollutants is far lower than the national standard.

5. Economic, ecological and social benefits

Through solid and effective work, straw compaction molding fuel has been widely promoted, the local waste straw has been effectively used, and remarkable economic, ecological and social benefits have been achieved.

Economic benefits: Through the promotion of technology, the district actually collected and stored 14,900 mu of straw and agricultural "three leftovers" (mainly including corn straw, peanut shell, and wasteland), processed 4,900 tons of biomass curing molding fuel (which can replace 3,266 tons of coal), and achieved 685,400 yuan of operating profit, with an average profit of 140 yuan/ton. In fact, more than 60 rural surplus labor force people are employed, and the income of rural residents is increased by more than 500,000 yuan, and the economic benefits are remarkable.

Social benefits: Through technology promotion, the final disposal of a large number of straw and agricultural residues in the region has been solved, which can promote energy conservation and emission reduction, replace coal energy consumption, eliminate the negative impact of incineration on the environment, guide farmers to abandon the bad habit of incineration, improve farmers' awareness of biomass solidified fuel products, improve air environmental quality, and promote a virtuous ecological cycle. It can promote the employment of rural surplus labor force, improve the income of rural residents, revitalize the rural economy, and has great significance for maintaining rural stability.

The promotion of biomass molding technology has made full use of crop straw, increased farmers' income, reduced the dirty rural environment and air pollution caused by straw stacking and incineration, promoted the construction of rural spiritual civilization and material civilization, and achieved good social benefits.

Ecological benefits: Guided by the concept of green development, with the approach of reduction, reuse and resource conversion, through the development of new energy models, waste into treasure, reduce coal consumption and reduce loose coal pollution, which is conducive to improving the village appearance. Using crop straw as raw material, fully excavating surplus value, effectively saving coal energy, protecting the agricultural ecological environment, is an important means to develop economical and recyclable agriculture, and has played a positive role in alleviating air pollution.

The popularization and implementation of straw comprehensive utilization technology in rural areas has special significance in saving non-renewable resources and alleviating power supply shortage. The energy utilization of straw not only reduces the harm caused by straw burning to the environment, reduces the emission of greenhouse gases and harmful gases, but also plays an important role in promoting the construction of new countryside. Biomass solid fuel is the fourth largest energy after coal, oil and natural gas, is a renewable resource that can replace mineral energy, and is a key development direction in the future.