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Technologies for control of sulfur and nitrogen compounds and particulates 167

Sulfur
recovery CO Exhaust gas
2
Electricity
Cooled Wet HCN/COS Carbon
raw gas scrubbing hydrolysis Desulfuration CO shift capture Power block

Sulfur
recovery CO Exhaust gas
2
Electricity
Cooled Wet Carbon capture
raw gas scrubbing CO shift /desulfuration Power block

Sulfur
recovery CO 2 Exhaust gas
Electricity
Cooled Wet Carbon
raw gas scrubbing CO shift Desulfuration capture Power block
Figure 6.11 Alternative sequences for H 2 S and CO 2 removal systems in integrated gasification
combined cycle, Hydrogen Cyanide (HCN) and Carbonyl Sulphide (COS).

corrosion. Previous experiments with the regulated injection of underground gas with
high concentrations of H 2 S seem to indicate that the joint storage of CO 2 and H 2 Sis
not technically unfeasible (Singh et al., 2009).

6.3.3 Hot gas cleaning in IGCC

To avoid the energy and efficiency requirement in IGCC due to the cooling of the syn-
thesis gas produced in a wet scrubber, the idea of gas scrubbing at higher temperatures
arises to increase the thermal efficiency of the plant.
It is considered that gas cleaning can be potentially beneficial at temperatures be-
tween 250 and 650 C, with pressures varying from 1 to 3 MPa, before its arrival at

the gas turbine. Said benefits, in addition to those related to thermal efficiency, influ-
ence both capital costs and operating costs because the volume of gas becomes lower
when the process is carried out before its arrival in the turbine.

6.3.3.1 Hot gas particulate removal
HTF is a prerequisite for the implementation of new technological advances in IGCC
such as dry desulfuration with solid sorbents, which works at temperatures between
250 and 600 C. The use of the dry desulfuration in an IGCC coal power plant can

increase the net efficiency by 10% and reduces CAPEX by 15% (Denton et al., 2015).
The most reliable option for hot particulate removal is to use a dry barrier filter sys-
tem. Although there are available commercial barrier filter elements with the ability to

operate at temperatures up to 730 C in IGCC conditions, the operation temperature of

existing filters in IGCC reported in the literature covers the range from 235 till 400 C
(Wang and Stiegel, 2017; Kosstrin, 2017). The development of new filters able to