Abstract:Binder is essential in cold-bonded pellets, and currently widely used organic and inorganic binders will lose their strength at high temperatures, resulting in a serious decline in pellets’ strength, such as CMC, bentonite and cement, etc. Thus, looking for a type of binder which has great high temperature performance is the key problem needed to be solve. Effects of binder, used in this study, on the compressive strength of the pellets at room temperature and high temperature were investigated,XRD and SEM-EDS were used to study the performance of pellets and raw materials, and the mechanism was also discussed. Results show that the binder exists in a flowing state in cold-bonded pellets, which could adsorb or enclose the iron ore particles.The addition of binder ratio could improve the strength of the pellets at room temperature and high temperature.When pellets are roasted under high temperature and reducing atmosphere,metallization ratio of pellets increases for the reduction of pellets, which results in an increase of the interspace between iron ore particles and a decrease of pellets’ strength. The change of strength and metallization is the most obviously when pellets are roasted for 30-90 min. In the early stage of roasting, strength of pellets does not decrease rapidly as well as pellets using other binders, and pellets could still maintain 100 N/pellet after roasted.
王榕榕,张建良,刘征建,刘依然,刘兴乐,李乃尧. 新型黏结剂强化冷固结球团的作用机理[J]. 钢铁, 2017, 52(11): 9-14.
WANG Rong-rong,ZHANG Jian-liang,LIU Zheng-jian,LIU Yi-ran,LIU Xing-le,LI Nai-yao. Hardening behavior and mechanism of a new type of binder on cold-bonded pellets. Iron and Steel, 2017, 52(11): 9-14.
Agrawal B B, Prasad K K, Sarkar S B, et al. Cold bonded ore–coal composite pellets for sponge ironmaking Part 1 Laboratory scale development[J]. Ironmaking & Steelmaking, 2000, 27(6): 421.
[2]
Agrawal B B, Prasad K K, Sarkar S B, et al. Cold bonded ore–coal composite pellets for sponge ironmaking Part 1 Laboratory scale development[J]. Ironmaking & Steelmaking, 2000, 27(6): 421.
[3]
Agrawal B B, Prasad K K, Sarkar S B, et al. Cold bonded ore–coal composite pellets for sponge ironmaking Part 2 Plant trials in rotary kiln[J]. Ironmaking & Steelmaking, 2001, 28(1): 23.
[3]
Agrawal B B, Prasad K K, Sarkar S B, et al. Cold bonded ore–coal composite pellets for sponge ironmaking Part 2 Plant trials in rotary kiln[J]. Ironmaking & Steelmaking, 2001, 28(1): 23.
[4]
侯希伦. 直接还原用铁粉冷固结球团[J]. 钢铁,1979(3):48.
[4]
侯希伦. 直接还原用铁粉冷固结球团[J]. 钢铁,1979(3):48.
[5]
El-Hussiny N A, Shalabi M E H. A self-reduced intermediate product from iron and steel plants waste materials using a briquetting process[J]. Powder Technology, 2010, 205(1): 217.
[5]
El-Hussiny N A, Shalabi M E H. A self-reduced intermediate product from iron and steel plants waste materials using a briquetting process[J]. Powder Technology, 2010, 205(1): 217.
[6]
Cevik E, Ahlatci H, Sun Y. Characterization and Reduction Behavior of Cold-Bonded Composite Pellets for Direct Reduction Using an Organic Binder[J]. Metallurgist, 2013, 57(5): 468.
[6]
Cevik E, Ahlatci H, Sun Y. Characterization and Reduction Behavior of Cold-Bonded Composite Pellets for Direct Reduction Using an Organic Binder[J]. Metallurgist, 2013, 57(5): 468.
[7]
Robinson R. High temperature properties of by-product cold bonded pellets containing blast furnace flue dust[J]. Thermochimica Acta, 2005, 432(1): 112.
[7]
Robinson R. High temperature properties of by-product cold bonded pellets containing blast furnace flue dust[J]. Thermochimica Acta, 2005, 432(1): 112.