Page 187 - Wastewater Solids Incineration Systems

154 Wastewater Solids Incineration Systems

FIGURE 7.7 A Venturi scrubber with bomb-bay dampers.

2.4.2 Advantages and Disadvantages
The Venturi scrubber is a relatively simple and effective particulate wetting and
removal device, provided that pressure drop can be adjusted to obtain the required
removal efficiency. A properly designed unit should have a variable throat section to
permit a constant pressure drop while gas volume processed by the system varies. A
Venturi requires a relatively clean source of water and a disposal point for the
processed water. At WWTPs, effluent is typically used. One of the primary disadvan-
tages of a Venturi scrubber is the significant power required by the incinerator
induced draft fan (or fluidizing air blower for a fluid bed incinerator) to accelerate
the flue through the Venturi. The higher pressures create stress for the induced draft
fan, which increases maintenance requirements. With a fluid bed incinerator this is
not a concern because most fluid bed incinerators in the United States do not have
induced draft fans. The higher pressures required by the Venturi scrubber can easily