Development of biomass pellet mill in China

Biomass pellet mill industry is a multidisciplinary and intersectant industry which focuses on research machinery design and processing, sawdust technology research, manufacturing of electric control system and software engineering in one with significant technology problem. Now few domestic colleges and universities and scientific research institution have certain success in the research of biomass pellet technology. Therefore, biomass pellet fuel has not been widely promoted and applied in our country due to the technology and financing issues and other reasons. In order to speed up the commercialization and industrialization of biomass pellet fuel in our country, we analyzed the existing problems during the promotion and applying process, and discussed the countermeasures and methods to solve the problem.

1. The development of biomass pellet mill at home and abroad 
At present, researching and developing biomass fuel technology is becoming a hot topic all over the world, and it has been concerned by the governments and scientists of every country. Many countries have formulated the corresponding development and research plan, among them, development and utilization of biomass pellet fuel has account for big portion. There are many foreign biomass fuel technologies and equipment has been applied commercially. And comparing with other biomass fuel technology, biomass pellet fuel is much easier to achieve the large-scale production and utilization. For instance, In USA, Sweden and Austria etc, the scale of applying account for 4%, 16% and 10% of disposable energy consumption desperately in these countries; in the United States, the total installed capacity of biomass fuel power generation is over 10000MW, the capacity of a sing machine is 10-25MW; in Europe and the United States, the biomass pellet fuel for residential and the matched high efficiency clean consumption heating stove is very popular, so the straw pellet mill or sawdust pellet mill is an ideal choice for the farmers to compress the biomass pellet fuel.



Our country concerned about the development and applying of biomass fuel. From 80th of 20 century, the national government has listed the research and applying of biomass fuel as the important scientific priority project and carried on the research and developing of new technology of biomass pellet fuel, which improves the biomass fuel technology increasingly. But the research and applying of biomass fuel in our country mainly focused on the biogas engineering technology in large-scale farmers, the technology of concentration gas supply of straw gasification and technology of waste landfill for power generation etc. the research of processing of biomass pellet fuel production and direct burning for use is just started.

2. Traditional method of making pellets and the new ETS pellet-making technology
At present, our country mainly adopt the traditional way of making pellets, it is the same with the modern way of making feed pellets, which the raw material enter into the inside of ring die, and compressed by the compression roller and discharge out from the ring die with the pellet shape. The technology includes drying of raw materials, compressing, cooling and package etc. The process requires to consume a large amount of energy and the materials is deformed and raised in temperature under the high pressure which the temperature is up to 100°C ～120°C ; the second is the moisture content is about 12%. Too high or low of moisture content can not making pellets. In order to make proper moisture content, the materials need to be dried before pelletizing. The third is that the compressed pellets require to be cooled before package. The energy consumption of the last two technology process account for 25%~35% of the total process, in addition, there is high mechanical wearing to the machine during the pelletizing, so the cost for traditional method of pelletizing product is high.

ETS (Eco Tre System) is a new type of sawdust pellet making production system which researched by Italian. It has high adaptabilities to the moisture content of the raw materials, which is proper to pelletizing when the moisture content is 10%-15%. The temperature of compressed pellets is usually about 55°C ～60°C . It is necessary to cool the pellets before package. Generally, the drying and cooling process could be removed. This method of making pellets has low power consumption (decrease about 60%-70% energy consumption comparing with the traditional process technology), the mechanical wearing is greatly reduced, so the total cost for production is reduced. For different raw materials, ETS system consume about80-180KWh/t per unit during the total production, the production cost is about 68~128$/t, while the traditional way of pelletizing for consumption per unit is 80~180KWh/t. From above, the production efficiency of ETS is improved evidently.

3 .Money problem 
The cost for producing biomass pellet mill and the assorted equipment is much higher, and the cost of each set is about several hundred thousand dollars. In addition, there are raw material purchase fee and material process fee as well as a large space for storage. For a new enterprise, it is necessary to process a certain scale of capital to ensure the normal operation of production. Also there is evident demand for floating capital. The sawdust pellet mill of the enterprise requires working with long time, stable performance and high efficiency, and it high request to the accuracy, stability and reliability of the production, which the processing accuracy of the spare parts of the sawdust pellet mill greatly affected the product quality. A lot of non-standard spare parts require to be produced for the enterprises; it is general to produce these spare parts by the cooperation process for the industry conventional way. Concerning about the processing accuracy of spare parts, technology confidential issue and other factors, the supplier of the heart spare parts and the existing large companies has established long term stable cooperation in the industry. As the advancement of technology, the spare parts suppliers and sawdust pellet production enterprise has developed together, so the most important problem for the new entered company is to improve the processing accuracy and mature technology of processing spare parts.



4. Policy support form the government
It brings good ecological benefits and social benefits to the development of biomass fuel. The France government believes that developing the biomass fuel not only protects the environment and mitigates climate change but also promotes the continuous development of agriculture; Every year, using the biomass fuel to replace of traditional fuel like gas and coal etc, could reduce about 1, 100, 0000 t imported original oil which are equal to save about 25billion to 30 billion Euros and reduce 16000000 carbon emission. The annual forest net consumption is 343950000M³ in our country, firewood account for 29.8%, it is about 102500000M³. If the firewood is made into pellets for power generation, the annual power generation capacity is about 1,230 billion kWh; the annual input value is 369billion which increase about 3690000 job opportunities. Therefore, the government should regulate the energy tax, environment protection tax and other policies to promote the development of biomass energy, to make the environmental protection consciousness deep into people’s heart.  

In all, china is starting to pay more attention to the development and utilization of renewable resources as the lacking of oil, gas and coal and growing of environmental pollution. As an ideal renewable resource, the biomass pellet not only realizes the recycling of renewable resources, but also reduces the air pollution. We believe that the biomass pellet mill industry is going to meet another spring soon.

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