1 INTRODUCTION
SOx and NOx are the most important sources of atmospheric pollution in
China. With the continuous implementation of environmental protection,
SO2 and NOx emissions have continued to decrease. In
recent years, the “ultra-low emissions” that have been bred and
implemented have put forward stricter standards for pollutant emissions
from energy-intensive industries such as coal-fired power plants. As a
flue gas desulfurization, denitration process that is expected to
achieve “ultra-low emission”, the activated coke (AC) flue gas
treatment process is widely used in China[1-5].
At present, AC flue gas purification mainly is a moving bed integral
reactor[6-10]. In the adsorption tower and
desorption tower, the AC move downward by its own gravity to complete
the denitration-desulfurization-regeneration cycle. During this process,
the large pressure pressing on AC in the lower part of the adsorption
and desorption tower may cause partial AC to crush. The friction between
the AC particles or the AC and the equipment may cause the AC to wear.
In addition to a small amount of chemical consumption during thermal
regeneration, the consumption of AC is mainly due to physical
damage[11]. Therefore, the AC mechanical strength
indicator, such as the compressive strength and abrasion resistance,
directly determine the service life of the AC[12].
A lot of research about the influencing factors of AC desulfurization
and denitrification performance has been done, but there are only a few
study on the influencing factors of AC mechanical strength, so it is
difficult to purposefully product the high strength AC. It is generally
believed that the developed pore structure leads to the looseness of the
AC skeleton, which deteriorates the AC mechanical strength, but the
specific pore structure characteristic index that affects the mechanical
strength of the AC are not clear. In addition, the micropore of
coal-based AC are developed and the mechanical strength is relatively
high, so it has been widely used in the field of flue gas
purification[13-14]. While, previous studies
failed to learn the influencing factors affecting the mechanical
strength of coal-based AC, because the AC type used in the research is
more complicated[15]. Therefore, this study takes
the coal-based AC commonly used in China as the raw materials to try to
clarify the pore structure characteristic index that affects the AC
mechanical strength, which provides a theoretical basis for the
production and purchase of high mechanical strength AC.