international network · (or kiln discharge hood) to prevent cold air entry or release of hot gas....

INTERNATIONAL NETWORK

ITECA SOCADEI SASBâtiment B3Rue Denis PapinLotissement du TourillonCS 3047813592 Aix en Provence Cedex 3FRANCE( + 33 (0)4 42 97 77 002 + 33 (0)4 42 97 77 33, [email protected], www.iteca.fr

Europe - North, Central & South America - Asia -Middle East - Africa

Aix en Provence

Paris

THREE DIVISIONS 1. On line colour analysis 2. Instrumentation (level detection, loading

trolleys, operating control…) dedicated to the solid bulk industry

(food, calcium carbonate, sugar, cement…)

3. Cement division:• - Analysers for on line process control• - Centralised laboratories• - Production equipments (kiln seals…)

ITECA SOCADEI - TODAY

PRODUCT RANGE

On line Process Control

Centralised Laboratory

Production Equipment

CEMENT DIVISION

On line Process Control

Free Lime Particle SizeComposition

Ignition LossAl - Fe - Ca - Si - S - P - K

CO2 - SO3

5/h2/h7/h 4/h Continuous

RAW MIX HOT MEAL CLINKER CEMENT

Crusher

Preblending

Additives

Raw Mill

Blending Silos

Precalciner

Kiln Cooler

Additives

CementMill

ClinkerSilo

Cement Silo

Quarry

Grinding media sorting machine

Inlet Seal Outlet SealGas sampling &analysis

Production Equipment

RAW MIX HOT MEAL CLINKER CEMENT

Crusher

Preblending

Additives

Raw Mill

Blending Silos

Precalciner

Kiln Cooler

Additives

CementMill

ClinkerSilo

Cement Silo

Quarry

"NEAR ZERO LEAK" KILN SEALS USING GRAPHITE BLOCK TECHNOLOGY

Kiln Seals

Inlet Seal

Inefficient Seals=

Energy & production capacity losses

Cold outside air

Hot gases are replaced by

Outlet Seal

Hot secondary air is replaced by

Cold outside air

Inefficient Seals=


LAMELLAR SEALThe metal plates are either burnt, worn out or loose their elasticity

Inefficient Seals=


Inefficient Seals=


DOUBLE LAMELLAR SEAL – INLET AND OUTLETEXAMPLE : 6 MONTHS AFTER INSTALLATION

Inefficient Seals=


DOUBLE LAMELLAR OUTLET SEAL

REVERSE LAMELLAR SEALThe metal plates are either bent out of shape, burnt or loose their

elasticity

Inefficient Seals=


FLOATING RING +PNEUMATIC PISTON TYPE SEAL

The piston rings wear out quickly

The floating ring is not maintained in contact with the kiln.

The floating ring is deformed and no longer touches on all points of

the circumference of the kiln

Inefficient Seals=


Inefficient Seals=


PISTON OUTLET SEAL - THE FLOATING RING DOES NOT FOLLOW THE MOVEMENT OF THE KILN

Inefficient Seals=


PISTON INLET SEAL - THE FLOATING RING IS BENT

Inefficient Seals=


PISTON INLET SEAL - SEVERE LEAKAGE

Inefficient Seals=


SPRING LOADED PLATE TYPE SEAL

The springs loose their elasticity due to the high temperature

The plates are not maintained in contact with the kiln.

It is not possible to retighten the springs when the kiln is in

operation

Inefficient Seals=


SPRING LOADED PLATE SEAL - THE PLATES ARE NO LONGER ALL IN CONTACT

Inlet seal : 4 meters diameter Kiln back end temperature: 1000°C Cost of energy : 0.01 US$/1000 KCal

Inefficient Seals=


0

50 000

100 000

150 000

200 000

250 000

300 000

20 25 30 35 40 45

Savi

ngs

in U

S$ /

year

Kiln back end pressure in mmH2O

10 mm gap8 mm gap6 mm gap4 mm gap

Outlet seal : 4 meters diameter Secondary air temperature: 900°C Cost of energy : 0.01 US$/1000 KCal

Inefficient Seals=


0

50 000

100 000

150 000

200 000

250 000

2 4 6 8 10 12

Savi

ngs

in U

S$ /

year

Hood pressure in mmH2O

20 mm gap15 mm gap10 mm gap5 mm gap

Inefficient Seals=


How to calculate the energy losses

Air flow = leak surface x air speed m³/s m² m/s Calculate the false air entries :

| ∆P| . 2 . g Air speed = v = —————— 2,5 . 1,3

1/2

Where air speed is a function of the pressure :

Energy savings = 1,3 x air flow x (1000 - 30) x 0,32 Kcal/s air density Kg/m³ m³/s °C Air specific heat Kcal/Kg.°C

Then calculate the energy savings according to the following formula (replace 1000°C and 30°C with the plant specific appropriate values) :

Cost of coal = 1 370 000 Dong/TonCalorific value = 6500 Kcal/KGCalorific cost : 1000 Kcal = 211 DongOr: 1 000 Kcal = 0,0087 €

And then calculate the monetary value of the energy savings using the cost of fuel including preparation cost (handling and grinding) :

• Provide effective leak tightness around the inlet chamber (or kiln discharge hood) to prevent cold air entry or release of hot gas.

• Improve pressure stability in the kiln

• Allow installations on existing kilns without modifying the kiln shell and the inlet chamber (or discharge hood)

• Limit maintenance to a minimum

• Improve cooling of the Nose Ring refractory plates.

KILN SEALDESIGN OBJECTIVES

OUTLET SEALDESIGN FEATURES

Kiln

GraphiteBlocks

Graphite Blocks are installed to form a static barrier between the discharge hood and a circular sliding track

rotating with the kiln

The blocks are maintained in placeusing cables and counterweights


OUTLET SEAL

Expected lifetime for the graphite blocks: from 4 to 7 years

Yearly wear: around 3 to 5 mmMaximum allowed wear: 150mm

Graphite = auto lubricating material maintenance reduced to a

minimum


When required a counter pressure is createdto prevent hot kiln gases from damaging the

graphite blocks

Fan and valve assembly


Graphite plateCable

T° probe

Graphite cooling system (fan + butterfly valve)

Nose ring plates cooling system

Clinker dust is collected in a hopperand returned to the drag chain


As an option it is possible to install

a new nose ring segment cooling

system with multiple nozzles


GRAPHITE BLOCKS

• Graphite plates arranged symmetrically & interlocked leak tightness enhanced

• Grooved metal insert at the top of each plate friction wear from the cables prevented

• Natural friction wear of the graphite constant efficiency of the leak tightness

Kiln

Graphite Block

Kiln inlet

Cooling ductSliding track

Shell

Graphite Blocks are installed to form a static barrier between the inlet chamber and a circular sliding track

rotating with the kiln

INLET SEALDESIGN FEATURES

Graphite blocks are air cooled Excess dust is evacuated through a hopper

INLET SEALDESIGN FEATURES

INLET SEAL AT NIGHT

INSTALLATION SCHEDULE

1 2 3 4 5 6 7 8 9 10

Check ovality shape and eccentricityFit bearing race supportFit bearing raceAdjustments, weld and checkFit bearing race links, weldFit leak tight casingConnection to the fume boxFit casing, adjustments, weldFit graphite plates cooling systemFit graphite plates, cables and counterweights,

TrialsKiln required to turn using the "inching motor"

TOTAL INSTALLATION TIME : 10 DAYS

KILN SEAL

REFERENCES&

TESTIMONIALS

38

Performance factor :Comparison of some key running parameters before

and after replacement of discharge sealBEFORE AFTER

COOLERTertiary Air Temp 800-850 DegC 900-950 DegC

Exhaust Air Temp 215-280 DegC 185-240 DegC

PREHEATERKiln Feedrate 175-195 tph 190-205 tph

Preheater Fan speed 800-820 rpm 750-810 rpm

Downcomer Temp 380-400 DegC 400-420 DegC

ATOX(Inleaks)

ATOX Feedrate 210 tph 235 tph

Recirculation Damper* 0 to 20% open 30 to 45% open

ESP Fan* 955-970 rpm 950-960 rpm

LAFARGE CAULDON UK

References

KILN SEALS

REFERENCE HOLCIM INDIA

KILN SEALS

ITECA HAS NOW INSTALLED 15 SEALS WITH HOLCIM INDIA

REFERENCES

• ITECA’s seal = Near Zero Leak Performance over the years (installed 2001)• Dust in the casing enters a double flap valve system into the cooler very clean atmosphere. The plant won an award for cleanliness

• Non-emission of clinker dust protection of mechanical components such as bearings, tires etc.

• Auto lubricating graphite blocks no maintenance work on the seal. Only the wire rope is changed during every shut down

• Ability to operate the hood (in case of outlet seal) under low negative pressures without any false air entries

OPERATIONAL EXPERIENCE

REFERENCE

KILN SEALS

CONCLUSION

Effective leak tightness = cold air entry prevented significant fuel savings

Effective leak tightness = pressure stability improved production increased

Benefits include:

• Adaptation on all existing types of kilns and easy installation

• Rotational, radial and axial movement absorption

• Absorption of kiln rotating defect

• Absorption of kiln expansion

• Efficient leak tightness resulting in increased lifetime of tyres, bearings… close to the kiln

• Very limited maintenance

international network · (or kiln discharge hood) to prevent cold air entry or release of hot gas....

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