April 4th 2013

AIChE Minutes
ChE 015
April 4, 2013
An AIChE meeting was held for assembly credit in DU 1107 at 1:30 p.m.
 Open house work night Sunday at 2 p.m.
Presenter: Geoff Greene from Westar, Jeffrey Energy Center in St. Marys, KS
o They produce 2400 Gross MW
o Largest in KS, 19th largest in the United States
o 259 Employees
o O&M Budget: $53.6 Million
o Fuel Usage: 9,000,000 Tpy
o Geoff Gave a coal analysis as well as an ash analysis
 Coal to Electricity is a Simplified Cycle
o Furnace 90’ by 160’
o 5,050,000 lb/hr steam
o 9 acres of heat transfer
 Emissions Control
o Flue gas goes to a precipitator which goes to ID fans and then to an absorber
 The precipitator is 98.5% efficient
 Scrubbers
o Remove SOx gasses
o Remove some particulates
 Limestone Storage
o 100,000 T/yr from Kansas City (better purity and Iron content than St. Marys)
 Limestone Ball Mills
o 2000 Hp
o 45 T/hr flow
o Ball size is about 3”
o 130 T of steel balls fills about 35%
 Limestone Product Storage Tanks (2)
o 350,000 gallons each
o 2.5 days storage
o Slurry pH is 6.0
o 20,000 gpm recycle pumps provide slurry
o Hydrocyclone for density control
 Absorber
o 4 modules/boiler
o Stainless steel
o Perforated trays increase contact time
o Mist eliminators prevent slurry carryover to the stack
 Dewatering and Blowdown
o Dewatering removes solids (gypsum)
Rotary Vacuum Filters
o 22” Hg
o Dries gypsum, removes by blade scraping
Gypsum Disposal
o 200,000-250,000 Tpy
To Landfill (bury)
o More than half the ash is hauled offsite for reuse
o They have capacity to contain ash for 25+ years and Gypsum for 35+ years
New Method Gypsum Reuses
o Portland Cement
o Ag
 Gypsoil (company) – fertilizer improves soil structure
Annual Sulfate Deposition
o Less deposition caused by reduced SO2 emissions and greener fertilizers
o Alfalfa, canola, corn soybeans
JEC Future Plans with Gypsum
o Market in 50 mile radius
o Expensive to transport (65% water)
o Expect $2 million to $4 million revenue from ash, gypsum sales
o Currently sell 10%, will increase in the next few years
Blowdown Building Treatment
o Coagulents
o Hg reduction
Solids Removal (Sludge)
o Produce about 5 Tpd
o Waste is mixed with gypsum and landfilled currently
o Pressure filters clean remaining solids from wastewater similar to a pool filter
Wetland Treatment System (Likely the Only System in the United States)
o Biological treatment
o Targets Se, Hg, F, B, Sulfates
o Research performed by KSU BAE
o Operation from 2011 to current
Pilot Design
o Parallel path with 4 cells
o Water flows cell to cell by gravity
o Has not hurt plants/environment
o Mass load reduction
 80% Hg
 90% Se
 40% B
It has been a success and they are planning a 40 acre design
o Larger flow rates and longer life
o 7,000 trucks of gravel/sand are required
o Expect 15 years before their rebuild
o Effluent is high enough quality for reuse, perhaps even discharging
Environmental construction since 2008 and future construction until about 2015
The total cost will be over $1 billion for environmental improvements and $1.5 million for
original plants