cement

An optimal process An optimal process

Today’s modern plant preheats raw Today’s modern plant preheats raw meal to calcination temperature in a meal to calcination temperature in a multi-stage cyclone

multi-stage cyclone preheaterpreheater. Most. Most of the calcination process takes place of the calcination process takes place in a separately fired, stationary calciner, in a separately fired, stationary calciner, while the remaining calcination and while the remaining calcination and clinkerization process takes place in clinkerization process takes place in a rotary kiln.

a rotary kiln.

FLSmidth has precisely what cement FLSmidth has precisely what cement producers need to make it an optimal producers need to make it an optimal process. With its low emissions, process. With its low emissions, flexibility and ease of operation, flexibility and ease of operation, the FLSmidth In-Line Calciner (ILC) the FLSmidth In-Line Calciner (ILC) preheater has been a success since preheater has been a success since its debut in 1976. And thanks to its debut in 1976. And thanks to our continual development of the our continual development of the system ever since, the ILC is still at system ever since, the ILC is still at the forefront of technology. Flexible the forefront of technology. Flexible enough to meet future demands as enough to meet future demands as well, the ILC can help plants stay in well, the ILC can help plants stay in the lead for many years to come. the lead for many years to come. How the ILC preheater works How the ILC preheater works Raw meal is introduced at the inlet gas Raw meal is introduced at the inlet gas duct to the Stage I (top) cyclones. It is duct to the Stage I (top) cyclones. It is subsequently preheated by hot, subsequently preheated by hot, countercurrent gas flow as it is countercurrent gas flow as it is continuously collected and passed continuously collected and passed down the other cyclone stages in the down the other cyclone stages in the preheater to the calciner. Fuel is burned preheater to the calciner. Fuel is burned in the calciner to achieve 92-95% of in the calciner to achieve 92-95% of the total material calcination before the total material calcination before collection in the bottom cyclone and collection in the bottom cyclone and entrance into the kiln. Combustion air entrance into the kiln. Combustion air for the calciner is taken from the kiln for the calciner is taken from the kiln via the riser duct and through a separate via the riser duct and through a separate tertiary air duct from the

tertiary air duct from the coolercooler..

Proven NO

Proven NOxx reduction from high reduction from high

temperature “stage-less” combustion temperature “stage-less” combustion is incorporated into the standard is incorporated into the standard design of the

design of the ILC preheater. It’ILC preheater. It’s a ves a veryry uncomplicated and effective way to uncomplicated and effective way to create low NO

create low NOxx emissions with only emissions with only

one firing location, one meal split and one firing location, one meal split and one tertiary air stream entering one tertiary air stream entering tangentially to the

tangentially to the calcinercalciner..

Our design is based on dividing the Our design is based on dividing the meal from the second-lowest stage meal from the second-lowest stage cyclone to the kiln

cyclone to the kiln riser and the calciner.riser and the calciner. These feed points are separated by an These feed points are separated by an expanded riser duct that forms a NO expanded riser duct that forms a NOxx

reducing zone. That is, the calcining reducing zone. That is, the calcining chamber is built (at least partially) into chamber is built (at least partially) into the kiln riser. All of the calciner fuel is the kiln riser. All of the calciner fuel is introduced to the kiln riser duct with introduced to the kiln riser duct with less oxygen than required for complete less oxygen than required for complete combustion, thereby forming a reducing combustion, thereby forming a reducing atmosphere.

atmosphere.

Above the reduction zone is the main Above the reduction zone is the main calciner vessel, which is divided into calciner vessel, which is divided into two or more sections separated by a two or more sections separated by a notch. The changes in cross-sectional notch. The changes in cross-sectional areas create turbulence that ensures areas create turbulence that ensures effective mixing of fuel, raw meal and effective mixing of fuel, raw meal and gas, improving heat transfer and gas, improving heat transfer and combustion. The calciner outlet loop combustion. The calciner outlet loop duct ensures optimum gas retention duct ensures optimum gas retention time, further mixing and complete fuel time, further mixing and complete fuel combustion.

combustion. Optionally

Optionally, the , the second- or third-lowestsecond- or third-lowest stage cyclone material can be further stage cyclone material can be further split to allow for diversion of a portion split to allow for diversion of a portion of the meal directly into the upper of the meal directly into the upper

Key benefits

Key benefits

-

-

Effective

Effective

emission

emission

control

control

-

-

Easy

Easy

operation

operation

-

-

Highly

Highly

reliable

reliable

-

-

Optimised

Optimised

fuel

fuel

and

and

power

power

consumption

consumption

-

-

Excellent

Excellent

suitabilit

suitabilit

y

y

for

for

low-grade fuels

low-grade fuels

-

-

Flexibile

Flexibile

design

design

for

for

easy

easy

upgrades

section of the calc

section of the calc ineriner. This creates a. This creates a “hot zone” in the lower section of the “hot zone” in the lower section of the calciner that is conducive to burning calciner that is conducive to burning difficult fuels and further NO

difficult fuels and further NOxx

reduction. reduction.

Design characteristics Design characteristics •

• Full capacity Full capacity range of range of today’today’ss plants of 13,000 tpd or more plants of 13,000 tpd or more •

• Built Built with with single single or or multiplemultiple preheater strings with up to 6 preheater strings with up to 6 cyclone stages

cyclone stages •

• Ratio of Ratio of firing in firing in calciner: 55-65%calciner: 55-65% •

• Calcination Calcination at at kiln inlet: kiln inlet: 92-95%92-95% •

• Allowable bypass Allowable bypass of kiln of kiln gas: 0-gas: 0-60%60% •

• For bypass For bypass of kiln of kiln gas up gas up to 100%,to 100%, special ILC version applies

special ILC version applies •

• Optional Optional “hot “hot zone” zone” in in lowerlower section of calciner

section of calciner •

• Available Available with with or or without without thethe HOTDISC™ combustion device HOTDISC™ combustion device reactor for burning coarse reactor for burning coarse alternative fuels

alternative fuels

Operating characteristics Operating characteristics •

• High-efficiency High-efficiency cyclones cyclones with with lowlow pressure drop resulting in low fuel pressure drop resulting in low fuel and power consumption

and power consumption •

• Lowest Lowest NONOxx emission from unique emission from unique

high-temperature reduction zone high-temperature reduction zone •

• Simultaneous Simultaneous low low CO CO emissionemission specially due to calciner notch specially due to calciner notch and outlet loop duct

and outlet loop duct •

• Uncomplicated Uncomplicated operation operation withwith single entry locations of calciner single entry locations of calciner fuel and tertiary air

fuel and tertiary air •

• Suitable Suitable for for firing firing both both traditionaltraditional and alternative fuels

and alternative fuels

1

1 Calciner Calciner outlet outlet loop loop duetduet

2

2 Meal Meal dividing dividing gategate

for “hot zone”

for “hot zone”

3

3 Meal Meal dividing dividing gate gate forfor

NO

NOxxreducing zonereducing zone

4

4 Calciner Calciner vessel vessel notchnotch

5

5 Optional Optional “hot “hot zone”zone”

6

6 TTertiary ertiary air air inletinlet

7

7 NONOxxreducing zonereducing zone

8

8 Optional Optional kiln kiln gas gas bypassbypass

9

9 Calciner Calciner firing firing pointpoint

1 1 2 2 3 3 4 4 5 5 6 6 7 7 8 8 99

5 stage In-Line Calciner 5 stage In-Line Calciner (ILC) preheater  (ILC) preheater 

Burn coarse alternative fuels Burn coarse alternative fuels Increasingly

Increasingly, plants , plants are burning solidare burning solid waste fuels to achieve a variety of waste fuels to achieve a variety of benefits. By integrating the ILC with benefits. By integrating the ILC with our HOTDISC combustion device, it is our HOTDISC combustion device, it is possible to achieve unsurpassed fuel possible to achieve unsurpassed fuel flexibility with minimal impact on flexibility with minimal impact on process stability and performance. process stability and performance. The HOTDISC is a safe, simple and The HOTDISC is a safe, simple and effective combustion device that has effective combustion device that has proven to be the best available proven to be the best available technology for substituting calciner technology for substituting calciner fuel with coarse alternative fuels. fuel with coarse alternative fuels. With the HOTDISC, plants can burn With the HOTDISC, plants can burn all kinds of solid waste in sizes up to all kinds of solid waste in sizes up to 1.2 metres. This eliminates the need 1.2 metres. This eliminates the need for expensive shredding of lumpy for expensive shredding of lumpy waste material.

waste material.

An optimal solution An optimal solution

Preheater and calciner design has a Preheater and calciner design has a strong influence on operational strong influence on operational efficiency

efficiency, emissions and , emissions and ability toability to effectively burn different types of effectively burn different types of fuels. Every FLSmidth preheater fuels. Every FLSmidth preheater calciner system is optimised for the calciner system is optimised for the individual situation in which it is to be individual situation in which it is to be used. FLSmidth’s decades of

used. FLSmidth’s decades of

experience in this area enables us to experience in this area enables us to deliver solutions that are ideal for deliver solutions that are ideal for each plant’s specific challenges. each plant’s specific challenges. These are some of the key These are some of the key factors that go into designing factors that go into designing an optimal solution:

an optimal solution:

1. Number of stages/cyclones 1. Number of stages/cyclones

FLSmidth’

FLSmidth’s s preheater preheater calcinercalciner systems are equipped with up to systems are equipped with up to six stages of cyclones. The number six stages of cyclones. The number of stages is normally determined by of stages is normally determined by the drying requirements in the the drying requirements in the different grinding systems. different grinding systems.

Emission requirements or other use Emission requirements or other use of the preheater exit gas can also of the preheater exit gas can also affect the number of stages, as can affect the number of stages, as can practical matters such as local practical matters such as local building codes/height restrictions. building codes/height restrictions. 2. Number of strings

2. Number of strings The

The number number of of strings strings of of cyclonescyclones is generally related to

is generally related to the plant’the plant’ss capacity requirements – the more capacity requirements – the more capacity needed, the more strings capacity needed, the more strings typically needed. Most

typically needed. Most commonlycommonly,, the system encompasses one or the system encompasses one or two strings, but more may be two strings, but more may be considered for the largest of considered for the largest of plants. A transition from one to plants. A transition from one to two strings relates to the size of two strings relates to the size of the cyclones and the resulting the cyclones and the resulting volume of the preheater volume of the preheater construction.

construction.

3. Size of cyclones 3. Size of cyclones

The

The selection selection of of cyclone cyclone sizes sizes is is aa balance of having the smallest balance of having the smallest cyclone dimensions while cyclone dimensions while maintaining the lowest overall maintaining the lowest overall pressure drop through the pressure drop through the preheater

preheater. This is to . This is to minimise theminimise the induced draft (ID) fan power induced draft (ID) fan power consumption – the most consumption – the most power-consuming part of a kiln system. consuming part of a kiln system. The

The size size of of cyclones cyclones relates relates to to thethe maintaining of desired gas velocity maintaining of desired gas velocity criteria and

criteria and efficiencyefficiency..

Increasing the preheater cyclone Increasing the preheater cyclone dimensions reduces the

dimensions reduces the pressurepressure drop. But for any given cyclone drop. But for any given cyclone geometry

geometry, stable , stable preheaterpreheater

operation (without raw meal falling operation (without raw meal falling through the riser ducts) requires a through the riser ducts) requires a certain minimum gas

certain minimum gas velocityvelocity..

Kiln gases Kiln gases  Ashes/residues  Ashes/residues Preheated raw Preheated raw meal inlet  meal inlet   Alternative  Alternative fuel inlet  fuel inlet  Tertiary Tertiary air  air  Emergency cold Emergency cold raw meal inlet  raw meal inlet 

Kiln riser duct  Kiln riser duct 

HOTDISC™ HOTDISC™ combustion combustion device device Rotating disc  Rotating disc  Scraper  Scraper 

Typical process flowsheet

Typical process flowsheet

of an ILC kiln system

of an ILC kiln system

-465 mm WG (4.5 kPa)

-465 mm WG (4.5 kPa)

1 Raw meal Raw meal feedfeed 2

2 Exhaust gasExhaust gas 3

3 Kiln gas Kiln gas bypass, bypass, if if anyany 4 Clinker

4 Clinker 5

5 Kiln burnerKiln burner 6

6 Calciner burnersCalciner burners 7

7 TTertiary ertiary air air ductduct 8

8 TTertiary ertiary air air duct duct damperdamper 9

Cyclones Cyclones

FLSmidth preheaters have been FLSmidth preheaters have been based on proven low

based on proven low pressure losspressure loss (LP) cyclones. The unique design of (LP) cyclones. The unique design of the LP cyclone ensures high thermal the LP cyclone ensures high thermal efficiency and low pressure drop while efficiency and low pressure drop while enabling a flexible and space-saving enabling a flexible and space-saving layout. LP cyclones have no horizontal layout. LP cyclones have no horizontal surfaces on the inside for material to surfaces on the inside for material to accumulate, thereby securing stable accumulate, thereby securing stable operation. The top stage has a special operation. The top stage has a special geometry to provide the lowest dust geometry to provide the lowest dust loss while maintaining low

loss while maintaining low pressurepressure drop. LP cyclones are not just for drop. LP cyclones are not just for completely new preheaters but may completely new preheaters but may be individually fitted to upgrade be individually fitted to upgrade existing preheaters.

existing preheaters.

Central pipes Central pipes

Central pipes (thimbles) are standard Central pipes (thimbles) are standard in all cyclone stages to provide high in all cyclone stages to provide high separation efficiency. The lowermost separation efficiency. The lowermost cyclones feature a cast, segmented cyclones feature a cast, segmented design with a hanging suspension design with a hanging suspension system and common elements system and common elements throughout. This enables easy throughout. This enables easy installation and maintenance. installation and maintenance. Sluice flaps and

Sluice flaps and distributiondistribution boxes

boxes T

To prevent gas o prevent gas from bypassing upfrom bypassing up through the material pipes between through the material pipes between the cyclone stages, the pipes are the cyclone stages, the pipes are equipped with sluice flaps (tipping equipped with sluice flaps (tipping valves) designed for full opening. valves) designed for full opening. Good meal distribution in the cyclone Good meal distribution in the cyclone riser ducts is ensured by adjustable riser ducts is ensured by adjustable spreader plates in the distribution spreader plates in the distribution boxes.

boxes.

Dividing gates Dividing gates

Robust dividing gates are used to Robust dividing gates are used to precisely and consistently distribute precisely and consistently distribute meal to the different sections of the meal to the different sections of the riser duct and ca

riser duct and ca lcinerlciner. One gate i. One gate iss capable of dividing meal into two, capable of dividing meal into two, three, or four

three, or four different streams.different streams. Tertiary air duct damper Tertiary air duct damper T

To balance the o balance the combustion air flowcombustion air flow between the kiln

between the kiln and calciner, aand calciner, a tertiary air duct damper is provided tertiary air duct damper is provided for reliable regulation of the tertiary for reliable regulation of the tertiary air gases. The damper design features air gases. The damper design features a solid refractory blade for long, a solid refractory blade for long, reliable life.

reliable life.

Cast segmented central pipe Cast segmented central pipe

Tertiary air duct damper  Tertiary air duct damper  Material pipe sluice flaps Material pipe sluice flaps

Meal dividing gate Meal dividing gate

Typical LP Typical LP cyclone cyclone

Upgrades and

Upgrades and

special solutions

special solutions

It is possible to upgrade virtually any It is possible to upgrade virtually any existing kiln system into the modern existing kiln system into the modern ILC – regardless of whether it comes ILC – regardless of whether it comes from FLSmidth or

from FLSmidth or another supplier.another supplier. This includes not only conventional This includes not only conventional suspension preheaters (SP) and other suspension preheaters (SP) and other calciner systems, but also complete calciner systems, but also complete transformations of long dry and wet transformations of long dry and wet kiln systems.

kiln systems.

SLC-D preheater calciner system SLC-D preheater calciner system As an optional preheater calciner system, As an optional preheater calciner system, FLSmidth also offers the SLC-D. With FLSmidth also offers the SLC-D. With its high-temperature pre-combustion its high-temperature pre-combustion chamber

chamber, the SLC-D , the SLC-D (Separate-Line(Separate-Line with Downdraft Calciner) offers unique with Downdraft Calciner) offers unique flexibility in fuel use.

flexibility in fuel use.

Choose it as a new system, or quickly Choose it as a new system, or quickly upgrade an existing ILC or SP

upgrade an existing ILC or SP preheater.

preheater.

The separate-line features of this The separate-line features of this system enable a substantial portion of system enable a substantial portion of the total retention time to be located the total retention time to be located parallel to the kiln riser duct. The parallel to the kiln riser duct. The placement of the combustion chamber placement of the combustion chamber outside the preheater structure makes outside the preheater structure makes this calciner design well suited for this calciner design well suited for upgrades, since downtime is minimal. upgrades, since downtime is minimal. The SLC-D combines the advantages The SLC-D combines the advantages of separate-line calciners with the low of separate-line calciners with the low NO

NOxx features of the in-line calciner features of the in-line calciner

when a portion of the calciner fuel is when a portion of the calciner fuel is directed to the kiln riser duct.

directed to the kiln riser duct.

1

1 Primary Primary firing firing pointpoint

2

2 Pre-combustion Pre-combustion chamberchamber

3

3 TTertiary ertiary airair

4

4 Optional Optional firing firing pointpoint

SLC-D type calciner  SLC-D type calciner 

Example of an ILC upgrade Example of an ILC upgrade into an

into an existing preheater existing preheater 

3 3 44 1 1 2 2

Fax: +45 3630 1820 Fax: +45 3630 1820 E-mail: info@flsmidth.com E-mail: info@flsmidth.com

E-mail:

E-mail: info-us@flsmidthinfo-us@flsmidth.com.com Tel: +91-44-4748 1000Tel: +91-44-4748 1000 Fax: +91-44-2747 0301 Fax: +91-44-2747 0301 E-mail: