What is claimed is:
Received 29 August ; revised 20 September ; accepted 15 October ABSTRACT Experimental study was conducted with regard to upgrading low-quality coal by low temperature pyrolysis technology and fluidization classification technology, which laid the theoretical foundation for research and development of low-quality coal upgrading process.
Firstly, a pyrolysis pilot experiment of long-flame coal was performed and the optimum pyrolysis conditions were found. It was found that the separating effect of coal particles was the most satisfactory when the inlet velocity at the bottom was 3.
Based on the test results, a novel process of low-quality coal upgrade and coupling was proposed, which realized the sorting, grading, drying and pyrolysis of low-quality coal through the multi-stage fluidized bed integrated process.
Under the current energy situation, to develop coal clean technology and to improve the utilization of coal are of great significance to alleviate the pressure of the future energy. A plenty of coal in low rank coal has high impurity high ash, high water and high sulfur characteristics, which is called the low quality coal.
Li Zhen, Yu Wei, Yang Chao and Zhou Anning pointed out that the treatment of low rank coal slime is an effective way on basis analysis in the comprehensive utilization of low rank coal and coal slime . Gu Xiaoyu had an experimental study on two kinds of Shenhua low rank coal of thermal modification qualitative processing researches.
The results showed that the thermal modification could significantly improve the coal quality characteristic of low rank coal, eventually getting low moisture and high calorific value and improving the ignition quality of modified products .
The Chinese Academy of Sciences Institute of the Development Process of Coal Topping Process BT process which uses fast pyrolysis, rapid separation and rapid cooling realizes priority use of tar oil and gas and solid products such as carbocoal which is used to generate electricity .
The reactor bed of circulating fluidized bed technology is composed by the grit with 0. The residence time is short, and the energy from the flue gases of pyrolysis by the electric heater and the liquefied petroleum gas and nitrogen gas preheated air fuel formation .
This paper is based on low temperature pyrolysis and fluidized bed coal particles classification tests of fluidized bed. Based on the results, the process integrated design of multi-stage fluidized bed was provided for the sorting, grading, drying and pyrolysis of low-quality coal in the integrated iron system.
On one hand, this design is conducive to complementary chiasma using of the waste heat in working procedures of iron making. On the other hand, the process integration design is in favour of the comprehensive utilization of low-quality coal. Furthermore, this new technology will reduce the cost of irons effectively, thus demand pressure of higher-order coal in steel industry will slow down.
Characteristics of Low Quality Coal The main features of low-quality coal are high impurity. High impurity content will not only reduce the quality of coal, but also increase transportation costs and processing costs.
If low-quality coal is directly used, it is easy to cause environmental pollution and energy waste. Taking sintering and coking as an example, with excessive moisture content, particularly with the high internal waters content in the coal, the water will break away from the surface of coal particles in the initial stage of accelerated warming, which is easy to cause the pores in the surface of coal particles ditch and even collapse and the sinter or coke exhibit more cracks.
Then the mechanical strength of the product is reduced, and energy is more consumed during the heating process. Similarly, when the coal particles conduct to the liquid phase reaction by heating it, the higher ash content will impact the liquid flow resistance and reduce the bonding effect.Abstract Gas fluidized bed collapse refers to the slumping behavior immediately following the cessation of gas flow.
This process is used in industry and academia for studying the ``fluidization quality'' of . Jun 09, · EP A2 describes the production of carbon nanotubes in a fluidized bed preceded by a reactor for in-line catalyst production, wherein the catalyst can have an average particle size of between 10 μm and 1, μm, and a growth in the volume of the agglomerates of up to twenty times the amount of catalyst can be achieved.
The experimental runs were carried out by keeping the fluidized bed velocity fixed (at m s−1) and by varying the equivalence ratio between and , so . The effect of temperature (between °C and °C) on gasification performance and sodium transformation characteristics of a high-sodium Zhundong coal was investigated using a novel design of fluidized bed gasifier.
Above the bed, i.e., in the freeboard zone of the combustion chamber of the fluidized bed, variations in temperature are observed. 2.
The maximum temperature at all the velocities is obtained at a height of mm from the bed and then a gradual reduction in temperature up to a height of mm occurs. International Journal of Chemical Engineering and Applications, Vol.
3, No.2, April Fuel Particle Size Effect on Performance of F Scribd is the world's largest social reading and publishing site.