[Home | Contact
Us]
Closed-Cycle SCWO Processing System
We will now discuss the principles of operation of the Closed-Cycle SCWO
Processing System (Figure 3). A key feature
of this design is to recover and re-utilize all process water at system
operating pressure without depressurization and water treatment external
to the process. Another key feature of this design is the recirculation
of cooled liquid effluent at system pressure for cooling and conditioning
of the reactor effluent. The features of the Transpiring-Wall SCWO Reactor
are covered elsewhere in more detail. (Transpiring-Wall
SCWO Reactor)
Principles of Operation
Waste is pumped, preheated and injected
at mixing nozzle (10) where it is mixed and reacted with supercritical water/oxidizer
mixture (9) within the waste injector and transpiring-wall reaction chamber.
The reaction byproducts are partially cooled and separated, with the vapor
phase extracted via port (1) for further processing as shown. With careful
control of separator conditions, the mass of water vapor leaving vapor outlet
port (1) together with the non-condensable exhaust gases is sufficient to
meet the water requirements of the process at location (9). To recover this
water for the process, the water vapor must be separated from the non-condensable
gases. This is accomplished by cooling the mixed vapor from port (1) and
separating the condensed liquid water. Cooling is accomplished via open
heat exchanger by the injection of cooled condensate directly into the hot
water/gas vapor mixture. Condensed water is collected in vessel (4) and
non-condensable exhaust gases extracted from the process via port (5). The
condensate is circulated back to the process by pump (6) and heater (8a)
which heats the water to supercritical temperature. The supercritical water
is then mixed with oxidizer from heater (8b) and injected into the process
at location (9). Water circulation rate can be adjusted independently of
waste flow rate.
Closed-Cycle SCWO Processing System
- Figure 3 -
The hot reaction by-products are quench-cooled by injection of cooled
brine taken from the bottom of the separator at location (11). Caustic or
other additives may be added to the brine prior to injection at port (16)
for the purpose of controlling corrosion, pH, solids, and effluent composition.
Free solids are removed from the brine by solids separator (13) and flushed
from the system via brine/solids outlet port (14). Brine circulation rate
can be adjusted independently of waste flow rate. The Transpiring-Wall SCWO
reactor design ensures that solids are positively and continuously flushed
from the system. (Transpiring-Wall SCWO Reactor)
Lower Operating Pressures
The Transpiring-Wall SCWO Reactor and Closed-Cycle Processing System can
be operated at either supercritical or subcritical pressures. At supercritical
pressures, heater (8a) (fig.3) would be a "once-through" type
heater. For subcritical pressure operation, heater (8a) would have to incorporate
both an evaporator section and a superheater section.
Advantages of Turbosystems Engineering's
SCWO Technology
These pages and their contents are the property of Turbosystems
Engineering Inc and may not be reproduced without the permission of the
company. Copyright © 2002 Turbosystems Engineering Inc. All rights
reserved. Any questions or comments, please e-mail us at Email Us