Analysis and Optimization of Mechanical Utility SystemPresented by: Kolambkar Deeptej Govind

Nandu Pooja KishorSinkar Kiran KashinathSohal Simran Avtarsingh

Project Objectives• To Carry out a detailed analysis of the mechanical utility

system.• Identification of a system which might require improvement and

optimization.• Increasing system efficiency by finding a feasible alternative to

the currently employed compression system.• Prediction and documentation of the monetary, power and

maintenance savings after replacement.

Compression System• Chemical plant operation requires pure nitrogen, obtained by adsorption

process.• Ambient air is compressed to a pressure of 7.7 Kg/cm2 in a 2 stage reciprocating

air compressor.

• The compressed air passes through a Carbon Molecular Sieve (CMS)

• Oxygen and other gases are adsorbed on the CMS surface & only nitrogen is passed to the storage cylinder.

• The required mass flow rate of nitrogen for chemical processes is 100 m3/ hr.

Utility System Floor Layout

Component Overview

• First bullet point here• Second bullet point here• Third bullet point here

Sr. No.

Component Name

Operating Parameters

Power Rating

Application

1. Reciprocating air compressor

Pressure Ratio= 7.454Flow rate = 257.407cfm

45 kW/ 60 hp

To supply compressed air to nitrogen filter.

2. Reciprocating air compressor

Pressure Ratio = 6.5 23 kW/30 hp

Used for operation of various pneumatic valves in MUS.

3. Reciprocating air compressor (20 TR)

Flow rate = 163.8 cfm 55 kW/75 hp

To supply compressed ammonia to brine chiller for cooling purpose.

4. Reciprocating air compressor (30 TR)

Flow rate = 245.74 cfm

70 kW/95 hp

To supply compressed ammonia to brine chiller for cooling purpose.

5. Nitrogen separator

Pressure = 5 kg/cm2

Flow rate = 61.72 cfm- Required for chemical processes.

Selecting an Alternative

Maintenance

• First bullet point here• Second bullet point here• Third bullet point here

Component Life Cost per unit

(Rs.)Maintenance time per unit Total cost per year (Rs.)

V-belt 3 months 1600 30 minutes 25,600

Piston Rings 6 months 2800 3 to 4 hrs. 11,200

Piston 2 to 3 years 12000 4 hrs 8,000*

Discharge Valves 4 months 3925 4 hrs 23,550

Suction valves 4 months 4250 4 hrs 25,500

Page 37 -39

Component Breakdown Frequency

Category 1 Category 2 Category 3 Category 40

1

2

3

4

5

6

Series 1Series 2Series 3

V-Belt Piston Ring Piston Discharge Valves

Suction Valves

Lubricant Oil Air Filters0

5

10

15

20

25

30

3

6

24

4 4 3

6

Frequency

Tim

e (i

n m

onth

s)

Page 40

Maintenance Down Time

Category 1 Category 2 Category 3 Category 40

1

2

3

4

5

6

Series 1Series 2Series 3

V-Belts Piston Ring Piston Discharge Valves

Suction Valves Lubricant Oil Air Filter0

100

200

300

400

500

600

700

800

30

240 240 240 240

5 15

120

480

160

720 720

20 30

Down Time per Unit Down time per year per unit

Tim

e (i

n m

inut

es)

Page 40

Total Maintenance Cost

27%

12%

8%24%

27%

0.2%

2%

V-Belt : Rs.25600Piston Rings : Rs.11200Piston : Rs. 8000Discharge Valves : Rs. 23550Suction Valves : Rs. 25500Lubricant Oil : Rs. 400Air Filters : Rs. 1900

Total cost : Rs. 96150

Page 42

Maintenance Time & Cost Saving

• First bullet point here• Second bullet point here• Third bullet point here

Component Time saved per Annum

V-belts 120 minutes.Piston rings 480 minutes.

Piston 160 minutes.

Total time saved 760 minutes = 12 hours 40 minutes.

Component Cost saved / AnnumV-belts Rs. 25,600.

Piston rings Rs. 11,200.

Piston Rs. 8,000.

Total maintenance cost minimized Rs. 44,800.Page 43; 44

Power Consumption & Savings

No load Full load05

1015202530354045

20

41

14

27

Operating Power Comparison

Reciprocating Compressor Screw Compressor

Load Condition

Powe

r (kW

)

Page 50

Load Cost Per Day

Reciprocating Compressor Screw Compressor0

500

1000

1500

2000

2500

3000

3500

4000

4500

5000

1131.9

700.7

4419.8

2910.6

No Load Full LoadCo

st p

er d

ay (i

n Rs

.)

Page 50;51;52

Savings Related to PumpingMotor Power (kW) 1.74

Electricity Cost

Saving (Rs.)

For a Day 321.55

For a Month 9,646.56

For a Year 1,15,758.72

The table shows saving in pumping cost if reciprocating compressor is replaced by screw compressor since latter does not require intercooler as it is single stage compression process.

Page 53

Saving in Compression Cost  Full Load No Load

Motor Power (kW) 14 8Electricity Cost Saving (Rs.)

For a Day 1,509.2 431.2For a Month 45,276 12,936For a Year 5,43,312 1,55,232

The table shows saving in motor power and electricity cost in compression process for full load and no load conditions if screw compression is used.

Page 52

Need for Efficiency Optimisation

Productive Demands

LeaksInnappropriate Uses

Artificial Demands

System Losses

Typically, only 50% of compressed air is used

for productive demands

Over 10 years, the energy cost will be 10 to 30 times the initial capital cost

Capital

Installation

Maintenance

Energy

Efficiency ImprovementRECIPROCATING COMPRESSOR

SCREW COMPRESSOR

Ideal work 27.829 kW 27.829kW

Motor Power 45 30

Efficiency=ideal/motor

61.84 % 92.76 %

Page 62 - 64

Floor Space Saving213

130

Dimensions are in cm.

Total Financial Savings

Contents Annual Savings

Pumping Cost 115758

Compression Cost543312 (full load)

155232 (no load)

Maintenance Cost 96150

Total Cost 9,10,452

THANK YOU