For the case of steam addition in the particle growth region, the
removal efficiency of fine particles is improved significantly, as can
be seen in Figs. 5b and 6. And the improvement of removal efficiencies
decreases with increasing the temperature of flue gas at the inlet
of spray scrubber. The reason is that supersaturated vapor
phase, necessary for the condensational growth of fine particles,
can be achieved in the particle growth region. Thus vapor can be
condensed on the particle surface, and the enlarged droplets can
be effectively removed by inertial forces. However, the temperature
and absolute humidity of desulfurization scrubbed flue gas
both increase firstly and then tend to stable with increasing the
temperature of inlet flue gas, which is illustrated in Table 2. The
measurements were carried out at the inlet and outlet of spray
scrubber with the temperature of desulfurization liquid being
34 C and the liquid-to-gas ratio (L/G) being 10 L/m3. What’s more,
the relative humidity of desulfurated flue gas takes a sudden drop
with the temperature of inlet flue gas. Therefore, the enhancement
of desulfurated flue gas temperature will cause the decrease of
supersaturation in the particle growth region with the same addition
amount of water vapor. Then less water vapor condensed on
the particle surface, leading to the smaller droplets, which are
comparatively difficult to removal by wire mesh demister.