FGD Gypsum Use in CementFGD Gypsum Use in Cement

Worldwide Cement ProductionWorldwide Cement Production

#1#1 ChinaChina#2#2 IndiaIndia#3#3 United StatesUnited States

US Cement IndustryUS Cement Industry

39 Companies39 Companies118 Cement Plants118 Cement Plants38 States38 States105 MM Metric Tons Consumed105 MM Metric Tons Consumed25 MM Metric Tons Imported25 MM Metric Tons Imported

US Cement IndustryUS Cement Industry

Announced Expansions:Announced Expansions:

–– 20072007 2,430M metric tons2,430M metric tons

–– 20082008 7,400M Metric tons7,400M Metric tons

–– 20092009 2,550M Metric tons2,550M Metric tons

Cement Clinker ChemistryCement Clinker Chemistry

(CaO)(CaO)33..SiOSiO22 and (CaO)and (CaO)22

..SiOSiO22

AlAl22OO33

FeFe22OO33

Raw Feed Components for Raw Feed Components for Cement PlantCement Plant

Calcareous Materials (providing Lime CaO)Calcareous Materials (providing Lime CaO)–– LimestoneLimestone–– Lime Mud (paper industry)Lime Mud (paper industry)

Argillaceous Materials (SiOArgillaceous Materials (SiO22 AlAl22OO33 and Feand Fe22OO33))–– SandSand–– Fly ash (power generation)Fly ash (power generation)–– Bottom ash (power generation)Bottom ash (power generation)–– Iron fines (steel industry)Iron fines (steel industry)–– Sand Blasting Waste (ship building industry)Sand Blasting Waste (ship building industry)–– Spent Catalyst (oil refining)Spent Catalyst (oil refining)

Preheater Precalciner Kiln

•There are five jobs to be done•Drying•Preheating•Calcining•Sintering•Cooling

Dry Process Preheater/Precalciner System

60%Fuel Split

40%

Rotary KilnRotary Kiln

Hot Hot ““ClinkerClinker”” Inside KilnInside Kiln

cement mill

clin

ker

gyps

umgy

psum

addi

tive

Separator

Fines

Finish Grinding Circuit

Rejects

Finish Grinding Mills (Cement Mill)Finish Grinding Mills (Cement Mill)

Ball MillBall MillFirst CompartmentUsed to crush clinker.

Second CompartmentUsed to grind clinker.

GypsumGypsum

Gypsum Added to Control SettingGypsum Added to Control SettingSet Time Increases as Gyp IncreasesSet Time Increases as Gyp IncreasesVarious Cement and Masonry Products Various Cement and Masonry Products Have a Range of SOHave a Range of SO33 ContentContentSOSO33 at 3.5% is a Typical Valueat 3.5% is a Typical Value

GypsumGypsum

““a product composed essentially of a product composed essentially of calcium sulfate in any hydration statecalcium sulfate in any hydration state…”…”CaSOCaSO44

..2H2H22OOCaSOCaSO44

. . ½½HH22OOCaSOCaSO44

Gypsum HandlingGypsum Handling

Natural Gypsum Generally Handles EasilyNatural Gypsum Generally Handles Easily

FGD Gypsum Generally More DifficultFGD Gypsum Generally More Difficult–– Slurry to Filter CakeSlurry to Filter Cake–– MoistureMoisture–– StickySticky

Gypsum HandlingGypsum Handling

Avoid Bucket ElevatorsAvoid Bucket ElevatorsMass Flow Cone Silo BottomsMass Flow Cone Silo BottomsMaterials of ConstructionMaterials of ConstructionReclaim Auger AssembliesReclaim Auger AssembliesReclaim Arm Assemblies Reclaim Arm Assemblies

Marine SilosMarine Silos

Cement BargeCement Barge