Download Troubleshooting vacuum systems : steam turbine surface

Troubleshooting
Vacuum Systems
Steam Turbine Surface Condensers
and
Refinery
Vacuum Towers
Authored
by
Norman P. Lieberman
<#>
Scri
Scrivener
Publishing
) WILEY
Contents
Preface
xiii
Introduction
xv
Definition of Terms
Other Books
1
How
Author
by
xxiii
Jets Work
1
1.1
The
1.2
Interaction of Steam Nozzle with
1.3
1.4
1.5
Converging-Diverging Ejector
Converging-Diverging Diffuser
Compression Ratio
Converging-Diverging Ejector
Velocity Boost
1
5
6
7
9
1.6
Surging
10
1.7
Critical
11
1.8
1.9
1.10
1.11
2
xix
Discharge Pressure
Observing the Conversion of Heat to Velocity
Jet Discharge Pressure
Reducing Primary-Jet Discharge Pressure
Bypassing First Stage Ejectors
Making Field Measurements
12
13
14
15
17
2.1
Getting
2.2
How to Unscrew Steel
2.3
Effect of Barometric Pressure
2.4
Use of Piccolo
25
2.5
Measuring Deep Vacuums using an Hg Manometer
Measurement of a Deep Vacuum without Mercury
Measuring Condensibles in Feed to First Stage Ejector
27
Identifying Loss of Sonic
31
2.6
2.7
2.8
Started
17
Plugs
vii
23
on
Boost
Indicated Vacuum
by Sound
24
28
30
viii
3
Contents
2.9
Identifying
2.10
Air Leaks in
2.11
Vacuum Measurement Units
3.1
Tidal
3.2
6
34
35
System Malfunctions
in Delaware
39
40
Critical
Discharge
Pressure
43
3.3
Fouling
in Final Condenser
43
3.4
Reduction in Back Pressure
45
3.5
Loss of LVGO Pan Level
45
3.6
Variations in
47
3.8
5
Flop
32
Flanges
Tabulation of Vacuum
3.7
4
Air Leaks
Water
Cooling
Temperature
Multi-Component Malfunctions
Partial Tabulation of Vacuum System Malfunctions
Effect of
Water
Partial Pressure
on
Jet Efficiency
Pressure of Water Limits Vacuum
50
51
55
4.1
Vapor
4.2
Reminder about Water Partial Pressure
4.3
Air
4.4
Variable
4.5
Loss of Sonic Boost
60
4.6
Relative Jet
62
4.7
Definition of "Vacuum
4.8
Critical
Leaks in Steam Turbine Surface Condensers
Cooling Water Temperature
Efficiency
Discharge
56
59
59
60
Breaking"
63
Pressure Exceeded
64
Air Leaks
67
5.1
Upper Explosive
5.2
How to Find Air Leaks
68
5.3
Diffuser Air Leaks
69
5.4
Air Leaks
70
5.5
Air Leaks in Heater Transfer Lines
71
5.6
Air Leaks
72
Sources and
on
-
Limits
67
Vacuum Towers
Turbine Mechanical Seal
Disposal of Hydrocarbon
Off-Gas
75
6.1
Evolution of Cracked Gas
75
6.2
Sources of Cracked Gas
78
6.3
Cracked Gas Evolution from Boot
80
6.4
Air
81
Equivalent
6.5
Overloading
Vacuum Jets
84
6.6
Excess Cracked Gas Flow
85
Contents
6.7
Checking Gas Flow Meter in Vacuum Service
Surging 3rd Stage Jet Bogs Down Primary Jet
85
6.8
6.9
Exchanger Leaks Overloads Jets
90
6.10
Poor Vacuum Tower Feed
Stripping
Level Connection Purges and Pump
92
Mechanical Seal Gas
94
6.11
6.12
Effect of Heater Outlet
6.13
Extracting H2S from Vacuum Tower
Off-Gas Upstream of Ejectors
Disposal of Seal Drum Off-Gas
Fouling of Waste Gas Burner
6.14
6.15
7
Field
95
97
99
100
101
7.1
Effect of Wet Steam
102
7.2
Water in Motive Steam
103
7.3
The Tale of Weak Steam
104
7.4
Internal
105
7.5
High Pressure, Superheated Motive Steam
7.6
Effect of Moisture Content of Saturated
Freezing
of Steam Nozzle
108
Temperature
108
7.7
Steam Pressure Affects Vacuum
109
7.8
Effect of
111
on
Superheated Steam
Mechanical Defects of
113
8.1
Steam Nozzle
113
8.2
Other Mechanical Defects of Jets
114
8.3
Fouled Steam Nozzles
117
8.4
Diffuser Erosion
118
8.5
Repair of Ejector Body
Changing Worn Steam Nozzles
Restoring Critical Flow
119
8.6
8.7
9
Temperature
89
Motive Steam Conditions
Steam
8
ix
Condenser
9.1
9.3
9.4
and
Cleaning
119
120
123
Fouling Mechanism in Condensers
for
9.2
Fouling
Ejectors
Testing
Refinery
Vacuum Towers
Fouling Due to
Minimizing
Chemical Additives
Condenser
123
124
Fouling
in Vacuum Towers
125
Fouled Pre-condenser
126
x
Contents
9.5
Fixed Tube Sheet Condensers
9.6
Cleaning
9.7
128
Condensers On-Stream
129
Condenser Bundle
9.8
Optimum
Configuration
Chemically Cleaning Condensers
9.9
Ball
9.10
Corrosion Control
Cleaning
Condenser Tubes
by
Better
11
Positive Feedback
130
131
Desalting
10 Pressure Control of Vacuum Towers
10.1
130
132
135
Loop
141
Condenser
143
11.1
Cooling Water Flow
Cooling Water Flow Configuration
Air Evolving from Cooling Water Reduces
143
Cooling Water Flow
145
11.2
11.3
Cooling
11.4
Tube Leaks
12 Condensate
Water Pressure to Surface Condensers
148
149
Back-Up in Condensers
151
12.1
Undersized Condenser Drain Nozzle
153
12.2
Seal Drum Level Indication
155
12.3
Leaking Gauge
12.4
Condensate
Pump Cavitation Due
12.5
Condensate
Back-Up
12.6
Experiment with Condensate Back-Up
Condensate Back-Up
12.7
13 Seal
13.1
13.2
13.3
13.4
13.5
13.6
13.7
13.8
13.9
Glass
on
Surface Condenser Boot
to Air Leaks
in Surface Condenser Boot
Leg Drainage
157
161
162
165
166
169
Sludge Accumulation in Seal Drum
Seal Leg Leak Inside Seal Drum
Seal Leg Flange Leak Outside Seal Drum
169
Seal
Leg Design
Inadequate Seal Leg Length for Hydrocarbons
Inadequate Seal Leg Capacity
High Back-Pressure from Seal Drum
Detecting Condensate Back-Up in Seal Legs
Condensate Back-Up Due to Air Leak
177
in Barometric Drain Line
186
13.10 Seal Drum
Design
171
174
180
182
183
184
188
Contents
13.11
Seal Drum Fills with Corrosive
13.12
Seal Drum
13.13
An Unfortunate Incident
14 Other
14.1
14.2
14.3
14.4
14.5
14.6
Deposits
194
Types of Vacuum Equipment
Hogging Jets
Use of Hogging Jet on Surface Condenser
Liquid Seal Ring Compressors
Gas Ejectors
Liquid Ejectors
Ejector Compression Efficiency
15.3
Impingement Plate in Surface Condensers
Mechanical Configuration of Seal Strips
Corroded Brass Seal Strips
Air or Vapor Baffle Leak
15.4
Identifying
15.5
Air Baffle Clearance
15.6
Fouling
15.2
Strips
197
198
200
202
203
204
205
206
208
208
209
211
Mechanism in Vacuum
212
15.7
Surface Condenser
212
15.8
Oversized
Impingement Plate
Impingement Plate
Impingement
Optimizing
Plates
Vacuum Tower
as
Vapor
214
Distributors
Steam to Heater Passes
16.2
LVGO Pan Level Loss Causes
16.3
Carry-Over of LVGO Pumparound Spray
Optimizing Vacuum Tower Top Temperature
Plugged Vacuum Tower Top Demister
Bypassing Primary Ejector
16.5
16.6
218
a
Loss in Vacuum
Frequently Asked Questions
17.1
Vacuum Systems
The Norm Lieberman DVD/Video
Index
215
217
Operation
16.1
16.4
17
Defective Seal
197
Tower Surface Condensers
15.9
16
189
193
Design Tips
15 Air Baffle and
15.1
xi
220
226
227
229
232
233
233
Library
243
247