基礎実験による微粉炭の熱分解・燃焼挙動の解析
1992 年 78 巻 7 号 p. 1206-1213
詳細
1992 年 78 巻 7 号 p. 1206-1213
Experiments concerning the combustion of pulverized coal in a free space was conducted using a vertical cylindrical furnace in order to make clear the combustion behavior of pulverized coal inside tuyeres of the blast furnace.
First, the influence of blast conditions and properties of pulverized coal on its combustion behavior were analyzed.
Secondly, the generated char from pulverized coal in stage of the pyrolysis were investigated.
(1) The amount of ultimate pyrolysis of pulverized coal increases with a rise in the blast temperature and a rise in the oxygen concentration accelates the pyrolysis rate. Accordingly, rising the blast temperature and oxygen concentration is conductive to the improvement of combustion efficiency inside tuyeres. Besides, the use of coarser coal and low volatile matter coal lowers combustion efficiency inside tuyeres. These are conceivably due to the lower pyrolysis rate caused by slow heat up and lower amount of ultimate pyrolysis, respectively.
(2) With the progress of pylorysis, pulverized coal became spherical and a lot of pores formed inside the particles. Moreover, the coal particles expanded as the pyrolysis proceeded with some kinds of coal. Accordingly, the reactivity of char is estimated to be higher than that of coke.
(3) Q-factor that fixes the amount of ultimate pyrolysis can be shown by the carbon content in coal, consequently the formula of pyrolysis rate with several different kinds of coal were presented.
