Old & Modern Continuous Centrifugals Operation /

Evaluation

By

Muhammad Mahmood(Process Manager)

Shakarganj Mills Limited, Jhang

Contents

• An overview of Continuous Centrifugal

• Different models of Continuous Centrifugal machines

• Selection of the type of Centrifugal machine

• Effect of rpm & Basket Angle

• Operational Parameters

• Worldwide manufacturers of Continuous Centrifugal

• Modern Continuous Centrifugal K 3300

• An overview of Continuous Centrifugal K 3300

Contents • Specifications of K 3300

• Function of different angle basket

• Comparison of crystal acceleration force of different basket

• High capacity with less power consumption of K 3300

• New two stage basket of K 3300

• Standard Screen arrangement of K 3300

• New rubber buffer design

• “Turbo 3” Product distributor

• Feeding Device of K 3300

Contents

• Split Spray nozzle lance of K 3300

• Basic Automation

• Operator Panel K 3300

• Comparison of technical detail of different centrifugals

• Technical Aspects

• Economic Aspects

• Conclusion

Introduction

Continuous centrifugals are in great demand in

the sugar industry due to their smooth running

and ease of operation. Recent development

work and extensive factory trails of modern

continuous centrifugals have shown particular

advantages in separation of the massecuite

into its constituents of shipment sugar &

molasses.

An Overview of Continuous Centrifugal

Different Models of Centrifugal Machines Installed in Sugar Mills

• Konti -12 DC

• Konti-1100

• FCB- 1250

• SK-1250

Selection of the type of Continuous Centrifugals Machine

• Basic Parameters for selection of the machine

Curing Capacity Tons/hr with given condition of

• Massecuite type and its :

i. Brix

ii. Purity

iii. Temperature

• Sugar Quality

i. Purity

Selection of the type of Continuous Centrifugals Machine

• Basket RPM

• Basket Diameter and Angle

i. Basket diameter at top

ii. Basket angle with respect to the tangential at the centre of basket

Effect of rpm and Basket Angle

• Rpm are selected with the massecuite type, normal recommended rpm and basket angle are as follow:

a. 1600/ 30º at A Massecuite

b. 1600 - 1800/ 30 º at B Massecuite

c. 1800 - 2000/ 34 º at C Massecuite

• High rpm beyond the recommended limit may cause:

a. Crystal damage

b. Reduce capacity curing

c. Decrease the V belts life

d. Decrease the bearing life

e- Ultimately risk operation of the Machine

Effect of rpm and Basket Angle

Low rpm against recommended limits may cause

• Low quality sugar production

• More molasses circulation in the system

Lesser degree basket against the recommended angle may cause/require :

• Resistance to travel the massecuite and sugar over the basket screen.

• More power demand for capacity run.

Effect of rpm and Basket Angle

Higher degree basket beyond the recommended angle may cause:

• Low quality sugar production

• More molasses circulation in the system

Start up Pre-cautions

1. Bearings are fully greased

2. Basket is fully tightened with housing unit.

3. Nickel working screens are fully tightened and sides are overlapped according to the direction of rotation and screen holding clamps are tightened.

4. No foreign material is present in the basket and massecuite distributor.

5. Top cover is placed and no air entering point left open in the casing or top cover.

6. Rotation of the machine with motor run.

7. Machine is steam heated to +/- 60ºC

8. Feeding pipe contains no cooled massecuite.

Start up Pre-cautions

9. Steam up the feeding pipe of pugmill at both side of the massecuite control valve to reduce the viscosity of the feeding massecuite at the start up and prevent the massecuite from entering the machine, during massecuite removing from pugmill feeding pipe , temporarily blind the feeding pipe of the machine .

10.Stop the steam heating when feeding massecuite and machine gained good operation temperature and machine came in normal operation.

11. Close the feed control valve and open the main massecuite control valve.

Start up Pre-cautions

12. Start the machine, after Delta run, start feeding massecuite and notice the over all behavior of the machine at operating conditions, after satisfaction, regulate the massecuite feed control valve.

13. Always use hot water of 60- 65 C immediate after the auger control valve along with massecuite feed to lubricate the massecuite for ease of equal distribution with in the distributor.

14.Very Important to regulate operation of the machine for good quality sugar production at designed capacity at recommended Ampere of the Machine. If there is

problem with operation at full load, check and rectify it do not leave it pending for next crop or compromise

at reduced capacity operation.

Operational Parameters

Use nozzle water spray at basket to maintain Sugar quality with following conditions:

• Distance not less than 50 mm• Water temperature 60 - 650C• Water pressure 2 kg/cm2

• Good spray is observed with fish tail type nozzles spraying at two points at 180 degree to each other.

Operational Parameters

Avoid over washing the sugar crystals, better check is to maintain molasses brix, If at recommended molasses brix sugar quality is not achieved then check other parameters like:

• Machine rpm• Number of V belts and tightening condition• Massecuite quality• Nickel working screen condition• Internal cleaning of the machine casing & distributor

Operational Parameters

Check and maintain:

• Cleaning the machine casing at defined interval

• Inspection of the sugar quality

• Hourly record the data for;

• Feeding massecuite temperature • Water spray temperature• Running Ampere of the machine• Bearing temperature • Sugar and molasses quality

Worldwide Manufacturer of Continuous Centrifugals

• BMA - Germany

• FCB – France

• Broadbent – England

• Silverweibull – Sweden

• Hein Lehman - Germany

• Western States – U.S.A

• Guangxi Su Group – China

• Patange- India

• Five Cail KCP-India

Modern Continuous Centrifugal

K 3300

• Newly designed K 3300 series Continuous

Centrifugal is highly sophisticated machine with

modern characteristics and efficient safe operation.

• Reduction in installation height and small space

requirement of the new design easy to install and

easy to assemble.

An overview of K 3300 Continuous Centrifugal

Specifications of K 3300

Basket Diameter 1,300 mm

Basket Angle 280 / 350

Screen Area 19,500 cm2

Max. gravity factor 2,906

Max. Speed 2000 rpm

Capacity for A-massecuite 35 – 45 t/h

Capacity for B-massecuite 22 – 35 t/h

Capacity for C-massecuite 15 – 19 t/h

Capacity for C-affination 22 – 30 t/h

Function of different Angle Basket

280 basket

300 basket

• Centrifugal basket angle determines at what proportion of the centrifugal acceleration is available to move the crystals up the screens and out of the basket.

Comparison of Crystal acceleration force of different basket angle

Basket Angle Basket Speed, RPM

Ratio of transport force, F

280 2000 7.3

300 1800 6.5

• Steeper basket at high rpm have high crystal acceleration force as where 300 basket has less crystal acceleration force

Salient Features of New Continuous Centrifugals

K 3300

High Capacity with Less Power Consumption of K 3300

• 25% Less power consumption as compared to old

continuous centrifugals.

• 15% Less wash water quantity.

• Better molasses brix which resulted less time on

pan boiling.

• Efficient massecuite processing with new turbo 3

distributor.

Main elements of new design

K 3300

• New two stage basket

• Upper diameter 1300 mm

• Pre - separation of syrup

with high throughput

• Harmonized sugar layer in

main separation stepBasket of K 3300

Standard Screen Arrangement

K 3300

• Wedge-wire screen at the

pre step

• Better sugar quality

• Reduce 25% energy

consumption subject to

massecuite quality

New rubber Buffer design K 3300

• Rubber buffers outside of heat affected zone

• Easy replacement of rubber buffer

New Motor arrangement

V-Belt tension monitoring

“Turbo 3” – Product Distributor K 3300

• Process Features

- Efficient heating for reduction of massecuite

viscosity

- Increase throughput

- Higher sugar quality

- Better massecuite distribution

- Easy assembling & easy accessible

“Turbo 3” – Product Distributor K 3300

Feeding Device K 3300

• Pneumatically operated

control valve

• Centering facility

• Compensator

• Sight glass (Temperature

resistant plastic)

• Double walled feeding

and heating pipe

Basic Automation K 3300

• Pneumatic acting valve

- for massecuite and

- mixing / melting medium

• Magnetic inductive flow meter

- for wash water and

- mixing / melting medium

Local Operator Panel K 3300

• Two controller for mixing or melting version

• Flashing light for less v-belt tension

• Flashing light for to high vibration

• Display for wash water consumption

Comparison of Technical Details Of Centrifugals Description Konti 12-DC K-1100 K 3300

Throughput, t/h

For A-mass

B-mass

C-mass

17 – 18

12 – 14

08 - 10

14 – 16

10 – 12

06 – 08

35 – 45

22 – 35

15 – 19

Basket diameter, mm 1265 1100 1300

Basket Angle 300 / 340 300 280 / 350

Maximum Speed, RPM 1800 2000 2000

Power consumption, Kw 75 75 90

Maintenance / Complexity

High / High Low / High Low / Low

Technical Aspects

K 3300

Technical Aspects K 3300

• Small space requirements and low installation

height allow a simple replacement of old

centrifugals

• High processing rate and best technological

results

• Optimum massecuite treatment prior to separation

to close filling system and large Turbo3 product

distributor

Technical Aspects K 3300

• Excellent separation effects to quick syrup

discharge and shifting of the crystals within the

basket

• Optimum running smoothness of the centrifugal to

newly designed overall structure

• Fewer malfunctions to high degree of automation

with automatic feed control and monitoring of

important functions

• High operational safety

Economic Aspects

K 3300

Economic Aspects K 3300

• Excellent value for money

• High Processing rates

• Improve process flow

• Low operating cost

• Long service life to use of stainless steel for parts

in contact with product and syrup

• Minimized maintenance costs to reduction of

wearing parts and improved access possibilities

Conclusion

• Improved and modern design of centrifugal requires less

application of water which results lower molasses purity.

• Enhancement in massecuite curing capacity with less

power consumption.

• Save loss in molasses by 1 to 1.5 degrees with

modernization which include:

- Better design of centrifugal

- Better design of centrifugal screens

- Better centrifugal operation

- Measuring operating parameters

Topic is open for discussion…