Equalization
FGD influent
Settling tank
Hg, As, heavy metals removal
Clarification
Nutrients and temp. control
Se bio-reduction Solid/liquid separation
Mixing tank
Mixing tank
Pre-
treat
men
t ta
nk
Bioreactor Discharge
• A relatively large footprint is required and chemical contamination may occur. • Bacteria are sensitive to temperature and additional nutrients.
Phys/Chem and Biological Treatment for Water Discharge
UKy-CAER Separation Modules
Ultrafiltra'onNanofiltra'on
CDI-1
HoldingVessel
CDI-2
Pumps
Sensors
CDI$combined$with$UF$and$NF$
Iron-based Electrocoagulation
In-house developed zeolite membrane
Continuous operation using CDI, UF, and NF
Our Approach Aimed at Water Discharge and Reducing Freshwater Intake FGD influent
Flotation with electrocoagulation Nanofiltration Zeolite
dewatering Continuous
capacitive deionization
Solids for landfill
Water recycle Solidification
Water recycle
Other uses
Water discharge Water reuse
• Develop an intensified process to remove toxic species by electrocoagulation, and reduce TDS/TSS using flotation and membrane-based filtrations.
• Practical salt concentration needs for solidification.
• Removal of the lower concentration regulated species by CDI.
• Process TEA .
Project Objective Preliminary Results – Using Electrocoagulation to Reduce Selenate Concentration in Liquid Phase
0"
5"
10"
15"
0" 10" 20" 30" 40" 50" 60"Selena
te"Red
uc3o
n"/"pp
b" Thou
sand
s"
Opera3onal"Time"/"min"
100#mA#
250#mA#
500#mA#
0 20min 55min11min
Expected Output • More effective solutions to meet ELG for
regulated species. • Promote water recycle in power plants. • Aid in understanding of water energy nexus.
@500mA
Acknowledgement • DOE/NETL: Barbara Carney and Briggs White • Duke Energy: Neil Kern • LG&E KU Energy: Mahyar Ghorbanian • UKy- CAER, CUMT, SR, and Trimeric.
Intensified Flue Gas Desulfurization Water Treatment for Reuse, Solidification, and Discharge (DE-FE0031555)
University of Kentucky Center for applied Energy Research
FGD Blowdown
Limestone slurry recycle
FGD scrubber Hy
droc
yclo
ne
Mechanical filtration
Slurry makeup
Recycle to FGD scrubber
Cl- removal for recycle
Gypsum production
Overflow
Water to be treated
• The Clean Water Rule requires treatment prior to discharge. • SeVI cannot be effectively removed by phys/chem treatment.
Flue Gas in
Flue Gas out