Pyro Interlocks-v0.0

PYRO SYSTEM - CONTROL LOOPS V0.0 Controlled Parameter

Actuator

Target

DATA TO BE FILLED BY PLANTS Control Loop Available in PCS (Y/N)

Comments

Small negative pressure, typically - 30 pa

In case of limited vent fan capacity, back fans in cooler set point should be adjusted by operator.

Y

Cooler drive speed

Maintain a constant depth of clinker in the clinker cooler

Drive 1 speed controls pressure, downstreem drives are slaved to drive 1 based on ratio. Grate 2 & 3 could also have independent control loops.

Y

Clinker Cooler EP inlet temperature

Fresh air adjustable damper

EP inlet temperature < limit defined by mechanical safety

Temperature based control by fresh air adjustable damper.

Clinker cooler compartment fans airflow

fan speed

According to suggested blowing density calculation

Clinker cooler firing hood pressure

Undergrate pressure of compartment one or two

Cooler Vent Fan

Y Fuel rate controls temperature to a set point that is normally in the range of 850 - 900° C

Gas temperature at final (lowest) cyclone stage.

Calciner fuel

Kiln feed bin level (weight)(need to be checked)

Silo Extraction

Kiln feed rate

Loop controls output to maintain kiln feed rate to set According to Operator or Lucie control. point. - Actuator depends upon dosing device

Feed rate is changed according to required production. Feed can also be raised or lowered according to kiln operating conditions, if kiln suffers severe cool outs, reducing feed rate will help the kiln to recover.

Kiln Feed

Kiln Speed

Maintain constant material loading of kiln.

Kiln speed will be adjusted based on kiln feed rate to maintain constant speed/feed ratio.

Grate speed 2 Grate speed 3

Grate speed 1 Grate speed 2

ID fan inlet temperature

Downcomer Water Spraying

According to whether raw mill is on or off.

Reduce gas volume to save ID Fan power

Main filter inlet temperature (for bag filter only)

Fresh air adjustable damper

Baghouse <240° C according to temperature rating for bags

ID fan exit pressure

Main filter fan speed or damper

Minimum negative pressure that will prevent over pressure in duct from ID fan to filter fan. Make downstream circuit independant from exhaust circuit

Too negative pressure should be avoided to prevent excessive false air, however increasing negative pressure can help ID fan flow if the production is fan limited.

Protection of bag filter, efficient ESP operation

Conditioning tower exit temperature is controlled by water sprays. The set point for GCT outlet temperature will depend on raw mill ON / OFF. It is important to monitor material temperature at bottom of GCT to avoid wet material.

Outlet Temperature GCT

GCT Water injection

Note:-

92 - 95% calcination of material entering the kiln

Y

Y

75%

Some of the values mentioned above may not be applicable for all plants. Plant need to set the values based on circuit configuration/supplier/OEM recommendation.

N N Y Y Y

Y

Y

Control Loop in Auto/Manual

Reason for run in Manual Mode

Comments [if any]

Clinker Pan Conveyor Clinker Breaker

Cooler Fan Damper

Grate Fan and Fan Damper

Clinker Storage


>HH

Depends on the distance

Clinker Transport

ON

OFF

120(need to be No transport of clinker checked)

Cooler Fan

Close

300

Cooler Filter fan

OFF

3

Kiln ID Fan (Stopped or Minimum Speed)

OFF

3

Kiln Hood Pressure

> HH

3

Cooler Filter inlet temperature


>HH

600

Cooler Filter inlet temperature Filter DP Cooler Filter Hopper Level


>HH >HH >HH

3 3 1800

Cooler Filter Fresh Air damper Cooler Filter inlet temperature


>HH

3

Grate 1 Drive

ON

OFF

300

Cooler Fixed Grate Fan

ON

OFF

600

Cooler Filter Fan

Kiln Drive

Kiln Feed Kiln Auxiliary Drive

Kiln Feed

Kiln ID fan and Fan Damper

Kiln minimum speed, operator should reduce kiln rpm during the stop delay Kiln to min. speed, no risk to the fixed grate since its well protect with a layer of clinker Operator decision to reduce kiln speed or to stop

300

ON

120

Kiln main drive Main Burner Fuels Calciner Fuel Gamma and cone pressure calciner cyclones level or bottom stage cyclones

ON ON ON

Stopped/minimum speed OFF OFF

300 120 3

If possible to have an automatic change over between main drive and auxiliary Kiln feed to stop or circulation or stopped Kiln feed to stop or circulation or stopped For ILC Kiln

> H (alarm only)

300

Immediate cyclone inspection for possible blockage

ID fan inlet temperature (Protection of impellor


>HH

3

Preheater Exit temperature


>HH

3

Calciner CO level Downcommer CO level ID fan inlet pressure


>HH >HH
3 3 3

ID fan outlet pressure


>HH

60

Kiln Filter Fan Cooler Filter Fan Kiln Feed Kiln Main Drive Kiln ID Fan Kiln ID fan Damper Calciner Outlet temperature

ON

3 3 120 300 3


OFF OFF OFF/recirculation OFF Stopped/Minimum Speed Closed >HH

Primary Air Fan

ON

OFF

3


>H(alarm) >HH >H(alarm) >HH >HH >H(alarm) OFF OFF/ Recirculation >H(alarm) >HH >H(alarm) >HH OFF >HH >H(alarm) >HH >HH ON HH OFF

20 3 20 3 2 60 3600 3 20 3 20 3 3 3 3 3 3 1200 3 3 1200


3

Protect against underpressure (particularly if GCT fitted)

Kiln Filter Differential Pressure


>HH

3

Protect filter bags

Kiln Filter Inlet Gas Temperature


>HH

3



Kiln ID Fan Kiln ID fan Damper

Shell Cooling Blowers

If bag filter to protect the bags. Auto operation of water spray system to control EP inlet temperature
OFF/ Recirculation

Kiln ID fan outlet pressure

ESP Tension Field

Protect bags

OFF

Calciner CO level Calciner CO level Downcommer CO level Downcommer CO level Kiln Hood pressure Kiln Hood pressure Nose Ring Fan Kiln feed Calciner CO level Calciner CO level Donwncommer CO level Donwncommer CO level Calciner Fuels Calciner Primary air blower Calciner Outlet temperature Bottom Cyclones Gas Temperature Bottom Cyclones Gas Temperature Downcommer CH4 level Kiln Filter Hopper Level Kiln Filter Outlet Pressure Kiln Filter Inlet Gas Temperature Kiln Filter Control Unit and Kiln Screw under filter Filter Fan Kiln ID Fan Outlet Pressure

Raw mill

> 50 Pa, All cooling fans to minimum flow except chamber 1&2, to prevent over pressure danger

Kiln main drive

Main burner Fuels

Kiln Filter Fresh Air Damper Open

Close to 0%, Operator should increase air to the fans either side of stopped fan. If fans from 4-8 stop the cooler can continue to run for a period if kiln output is controlled accordingly. Note that wear rate will increase on side seals in effected area. In a well sealed modern cooler the grate has to be stopped to avoid dust penetration into the plate slots. Follow OEM recommendation All cooling fans to minimum flow except chamber 1&2, to prevent over pressure danger 10% of setting, stop fan and damper to 0% if both kiln and filter ID fans are stopped

3

ID fan trips and damper closes to prevent deformation of impellor and shaft, H at 420C, HH at 450C Applicable for plants having water spray in downcomer to protect the duct, HH at 500C

LL is the design underpressure of the downcomer Minimum speed If raw mill stopped. If H is reached, increase exhaust fan if existing margin, if not ID fan and feeding should be limited Prevent over pressure

Alarm at 920C, HH at 1000C Main burner fuel stops. Standby primary air(if available) to start. Delay of main burner fuel stop will depend on time required to start standby PA fan Burner fuel to minimum Burner fuel to minimum

To protect Kiln outlet seal Calciner Fuel to minimum Calciner Fuel to minimum

Reduce calciner fuel Prevent kiln flush Protect Bags Protect filter from underpressure Protect filter bags

>HH

60

Interlocks coverd in Raw Grinding also

Stopped or Minimum Speed

3

Interlocks coverd in Raw Grinding also

Closed

3

Interlocks coverd in Raw Grinding also

Downcommer CO level


>HH

3

>0.8% CO to prevent explosion

Downcommer CH4 level Kiln Main Drive


>HH OFF

3 3

To prevent explosion Prevent kiln shell deformation