Direct Contact LLC (DCLLC) Heat Recovery Vessels have two configurations:
single- and dual-chambered. If the flue gas is relatively 'clean' or if particulate
matter does not have an adverse effect on the contact water quality, then a single-chambered
vessel can be used. In a single-chambered vessel, vapor is conditioned and heat
is recovered in the same chamber.
However, if particulate loading is heavy or degrades the contact water, then a dual-chambered
vessel is often used. The first chamber of the vessel is the vapor-conditioning
chamber, where exhaust gas is adiabatically cooled and particulates are removed.
This chamber combines cyclonic action and particle accumulation via condensation
to remove contaminants, and works especially well with hygroscopic (literally, "water-loving")
The patented DCLLC Heat Recovery Vessel generates a controlled
stream of liquid droplets that are directly contacted with hot flue gas. The large
surface area generated by sprays of small droplets efficiently transfers heat from
the gas to the liquid. Heat transfer coefficients are over an order magnitude larger
than those achieved by traditional indirect heat exchangers. The direct
contact surfaces of the spray droplets are continuously regenerated and
never foul, while the pressure drop developed through the vessel is significantly
lower than that of solid-surface heat exchangers.
DCLCC Heat Recovery Systems are designed to remain “transparent" to the process,
thereby not affecting operations sensitive to backpressure and allowing for periodic
maintenance and inspection without requiring process downtime.