Download Troubleshooting vacuum systems : steam turbine surface
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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