Seal

NCB CEMENT SEMINAR ITECA

NEW DEHLI, 28 JANUARY 2002

"NEAR ZERO LEAK" KILN SEALS USING GRAPHITE BLOCK TECHNOLOGY PRESENTED BY A. HAIDER OF ITECA France AND R.K. TRIPATHI OF LAKSHMI CEMENT INDIA

INEFFICIENT SEALS = ENERGY LOSS + PRODUCTION CAPACITY LOSS

HOT SECONDARY AIR IS REPLACED WITH COLD OUTSIDE AIR

KILN DISCHARGE SEAL

INEFFICIENT SEALS = ENERGY LOSS + PRODUCTION CAPACITY LOSS

HOT GASES ARE REPLACED WITH COLD OUTSIDE AIR

FEED END SEAL

INEFFICIENT SEALS = ENERGY LOSS + PRODUCTION CAPACITY LOSS

LAMELLAR SEAL

INEFFICIENT SEALS = ENERGY LOSS + PRODUCTION CAPACITY LOSS

REVERSE LAMELLAR SEAL

INEFFICIENT SEALS = ENERGY LOSS + PRODUCTION CAPACITY LOSS

FLOATING RING + PNEUMATIC PISTON TYPE SEAL

Savings in US$ / year

INEFFICIENT SEALS = ENERGY LOSS + PRODUCTION CAPACITY LOSS 180 000 160 000 140 000 120 000 100 000 80 000 60 000 40 000 20 000 0

20 mm gap 15 mm gap 10 mm gap 5 mm gap

2

4

6

8

10

12

Hood pressure in mmH2O

Kiln discharge seal : 4 meter diameter – secondary air temperature 900°C 330 days year

Savings in US$ / year

INEFFICIENT SEALS = ENERGY LOSS + PRODUCTION CAPACITY LOSS 200 000 180 000 160 000 140 000 120 000 100 000 80 000 60 000 40 000 20 000 0

10 mm gap 8 mm gap 6 mm gap 4 mm gap

20

25

30

35

40

45

Kiln back end pressure in mmH2O

Kiln inlet seal : 4 meter diameter – kiln back end temperature 1000°C 330 days year

ITECA

KILN SEAL DESIGN OBJECTIVES

• Designed, installed, tested and patented by Lafarge Cement France • Provide effective leaktightness around the kiln discharge hood to prevent cold air entry or release of hot gases and particles. • Improve pressure stability in the kiln. • Allow installations on existing kilns without modifying the kiln shell or the discharge hood. • Limit maintenance to a minimum • Improve cooling of the Nose Ring Refractory Plates.

DISCHARGE SEAL DESIGN FEATURES

ITECA

Kiln

Graphite Blocks

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

ITECA

DISCHARGE SEAL DESIGN FEATURES The blocks are maintained in place using cables and counterweights

ITECA

DISCHARGE SEAL DESIGN FEATURES

Expected life for the graphite blocks : Between 3 to 5 years

ITECA

DISCHARGE SEAL DESIGN FEATURES

Graphite blocks are air cooled

Clinker dust is collected in a hopper and returned to the drag chain

ITECA

DISCHARGE SEAL DESIGN FEATURES

As an option it is possible to install a new nose ring segment cooling system with multiple nozzles

INLET SEAL DESIGN FEATURES

ITECA

Kiln

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

ITECA

INLET SEAL DESIGN FEATURES

Graphite blocks are air cooled

Excess dust is evacuated through a hopper

VIDEO PRESENTATION LAKSHMI CEMENT

Kiln with existing seal Kiln just after Iteca graphite seal installation Kiln after 90 days of operation