Cold and Chilled Storage Technology

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Cold and Chilled Storage Technology

Second edition

Edited by

CLIVE V.J. DELLINO Refrigeration and Cold Store Consultant

Hunstanton, UK

fill BLACKIE ACADEMIC & PROFESSIONAL

An Imprint of Chapman & Hall

London· Weinheim . New York· Tokyo· Melbourne· Madras

ISBN-13: 978-1-4612-8430-7 e-ISBN-13:978-1-4613-1127-0DOI: 10.1007/978-1-4613-1127-0

Contents

Contributors XIll

Preface xv Preface to the first edition XVll

1 The cold storage chain 1 M. YOUNG

1.1 Introduction 1 1.2 Bulk stores and associated services 2

History 2 Building construction 3 Regulations and standards 5 Traffic flow 6 Mechanization 6 Layout 6 Storage methods 7 Stacking material 16 Fork-lift truck handling equipment 22 Administrative routines 24 Additional services 27 Development 29

1.3 Distribution depots 29 Introduction 29 History 30 Recent developments 32 Construction and equipment 35 Distribution depot operations 36 The current situation 39 Future developments 43

1.4 Distribution vehicles 47

2 Controlled atmosphere storage 53 D. BISHOP

2.1 Introduction 53 2.2 History 53 2.3 Definitions 56 2.4 Produce storage conditions 57 2.5 Ethylene 58 2.6 Pre-storage chemical treatment 60 2.7 Storage rooms 61 2.8 Expansion bags 62 2.9 Store leakage specifications 65 2.10 Refrigeration 66 2.11 Humidity and water loss 67 2.12 CA machinery selection 68 2.13 Oxygen removal 69

Natural respiration 69

vi CONTENTS

Liquid nitrogen 69 Propane burners 70 Ammonia crackers 70 Pressure swing 71 Membranes 71 Comparison of technologies 73

2.14 Carbon dioxide removal 73 Lime 73 Carbon scrubbers 74 Flushing 75

2.15 Ethylene removal 76 2.16 Instrumentation 77

Temperature measurement 77 Temperature sensors 78 Oxygen measurement 78 Carbon dioxide measurement 79 Ethylene measurement 81 Humidity measurement 81

2.17 Gas sampling systems 81 2.18 Store atmosphere control 83

Oxygen control 83 Carbon dioxide control 84

2.19 Automatic control 84 2.20 Regulations 86 2.21 Safety 86

Low oxygen 86 High carbon dioxide 87 Fork-lift trucks 87

2.22 Store operating practice 88 2.23 Distribution of CA produce 89 2.24 Future developments 90

Greater variety of product 90 Reduced use of chemicals 90 Transport 90

Acknowledgements 91 References 91

3 Automated cold stores 93 D. BRITT

3.1 Introduction 93 3.2 'Push' model supply chain 94 3.3 'Pull' model supply chain 95 3.4 Tools and barriers 96 3.5 Changing expectations 97 3.6 Changing technology 99 3.7 Base level cold/chilled considerations 105 3.8 Case-handling technologies 106

'Smart' conveyor systems 106 Carousel 107 Mini-load AS/RS 108

3.9 Unit load technologies 109 Radio-frequency and push-back racking 109 Unit load AS/RS 110 Unit load HDDS 110

3.10 Future technologies 112 3.11 Case handling HDDS 112

CONTENTS Vll

Vertical and deep-lane handling 112 3.12 Unit load HDDS 113 Reference 114

4 Refrigerant choice and energy use 115 N.J. COX

4.1 General background leading up to the adoption of CFCs 115 4.2 Ozone depletion and global warming 115 4.3 Total equivalent warming impact 118 4.4 Temperature glide 118 4.5 Refrigerant nomenclature 119 4.6 HCFCs as interim solutions 121 4.7 HFCs as the original long-term solution 122 4.8 Environmental problems associated with HFCs 124 4.9 Natural refrigerants and 'not in kind' technologies 125 4.10 Absorption 126 4.11 Air-cycle refrigeration 127 4.12 Water vapour 128 4.13 Carbon dioxide 129 4.14 Hydrocarbons 130

Specimen risk assessment for hydrocarbon refrigerants (to comply with UK regulations such as CDM) 132

4.15 Ammonia 133 4.16 Secondary refrigerants 136

Monopropylene glycol 136 Brine 136 Carbon dioxide 136 Silicone oil 136 Flo-ice 136 Organic salts 137

4.17 Refrigerants beyond the crisis 137 4.18 Indirect global warming and energy conservation 138 4.19 Energy conservation for cold stores 140

Automatically corrected power factor correction 140 Compressor motor control 141 Electronic evaporator control system 141 Floating head pressure and pack control 142 Maintenance and monitoring 142 Lighting 143 Cold store maintenance 143 Heat recovery 143 Use of cheap-rate electricity 144 Automatic non-condensable gas purgers 144 Refrigerated loading docks 144 Selecting the right condenser 144 Additional measures 145

4.20 Conclusions 145

5 Store insulation 147 B.A. RUSSELL

5.1 Historical background 147 The need for insulation 147 In situ cold storage 147 Early design and techniques 148 Conventional systems 149

5.2 Modern developments 150

viii CONTENTS

5.3 Insulation materials 151 Expanded polystyrene 151 Extruded polystyrene 151 Polyurethane and polyisocyanurate 152 Phenolic foam 153 Cork board (vegetable cork) 153 Glass fibre 154

5.4 Insulation applications 154 Internal insulated systems with external wall and roof cladding 155 External insulation system 155 Internal insulation system with external roof and partial external

wall cladding 156 5.5 Types of cold store panel 157

Continuous laminated panels 157 Composite panels 158 Foam-injected panels 159 Continuous foamed panels 159

5.6 Present-day design criteria 159 5.7 Internal pressure relief valves 160 5.8 The importance of vapour seals 161

Walls and roofs 161 Floors 164

5.9 Thermal bowing 164 5.10 Construction methods 167

Internal insulated systems with external cladding to walls and roof 167 Internal insulation with external roof and partial external cladding 170 External insulation systems 170 Floor insulation 171

5.11 Underfloor heating 173 Circulated glycol system 173 Low-voltage electric heater mat 174 Structural raised base slab 175 Vent systems 175

5.12 Specification for internal floor finishes 177 Cooling the store down to temperature 178

5.13 Insulated doors 178 Door protection 181

5.14 Erection plant 182 5.15 Technical data 183 5.16 Regulations and standards 184

UK requirements 184 International Association of Cold Storage Contractors (IACSC) 186 European requirements 186 US requirements 186

5.17 Current development trends 188 Industry needs 188 Structural alterations 189 Alternative finishes for cold store panels 189 Materials suitable for extreme climatic conditions 190 Thermographic scan 191

6 Cold store doors 192 T.FENTON

6.1 Introduction 192 6.2 Air infiltration 192 6.3 Door construction 193 6.4 Automation 198

CONTENTS IX

6.5 Controls 201 6.6 Installation 203 6.7 Protection 203 6.8 Special doors 205 6.9 Safety and maintenance 209 6.10 Conclusions 210

7 Refrigeration plant 211 A.J.PITT

7.1 Introduction 211 7.2 Refrigeration systems 217

Direct expansion 217 Natural flooded 219 Pump circulation 219 Secondary systems 220

7.3 Power comparisons and running costs 220 7.4 Use of waste heat 222 7.5 Defrosting methods 225 7.6 Monitoring and controls 228 7.7 Maintenance 230 7.8 Current development trends 230

Emphasis on rotary compressors 230 Variable-speed drive motors 231 Electronics 232 Heat exchange 232 Refrigerant 232

7.9 Safety and quality 233 7.10 Reacting to the environmental challenge 234

New plant 234 Existing plants 236

8 Electrical installations 238 M.CARR

8.1 Introduction 238 8.2 Electricity: the starting point 239

Generation 239 Transmission and distributipn 240 Tariffs 241 Metering 241

8.3 Control systems: computerised refrigeration 242 Temperature recording and control 243 Programmable controllers 244 SCADA systems 246 Computers for office and plant 248

8.4 Lighting: comfort and safety 248 General lighting 249 Emergency lighting 252

8.5 Alarm systems: protecting life and property 253 Fire alarms 254 Gas and vapour detection systems 256 Trapped personnel alarm systems 257 Security systems 258

8.6 Cold store installations: specific requirements 258 Refrigerated vehicle sockets 258 Frost heave protection 260 Door opening/closing systems 260

X CONTENTS

Standby power 261 Energy saving 262

8.7 Conclusion 263

9 Racking systems 264 RG.D. SHOWELL

9.1 Introduction 264 9.2 Standards 264

FEM 10.2.02 265 9.3 Basic unit of storage 266 9.4 Storage concepts 270

Block stacking 270 Pallet racking 273 Live storage 280 Double-deep static racking 281 Push back racking 283 Powered mobile racking 283

9.5 Comparisons of racking systems 294

10 Mechanical handling 295 J. ROPER

10.1 Today's market 295 10.2 Cold store operation 296 10.3 Trucks for all reasons 298 10.4 Lifecycle cost -efficiency 305 10.5 Case studies 307 10.6 Ergonomics 309 10.7 Communications 311 10.8 Rental benefits 312 10.9 The future 313

11 Vehicle movement and loading bay design 315 A.K. THOMSON

11.1 Introduction 315 11.2 Vehicle movement 315

Gates and approaches to roadways 317 Roadway surfaces 317 Roadway width 318 Turning circles 318 Traffic control 318 The loading/unloading area 318 Side-loading versus end-loading 319 Dock width 319 Flush loading bays 320 The approach to loading ports 320 'Saw-tooth' loading bays 320

11.3 Loading dock height 321 The bridging incline 322

11.4 Temperature control 322 11.5 Buffers, restraints and doors 322 11.6 Ancillary equipment 323 11.7 The loading bay as a total package 323

Dock levellers 323 Edge or front-of-dock levellers 324 Selection of dock buffers 325

CONTENTS

Hydraulic scissor-lift tables Port seals Inflatable dock shelters Combination foam dock pads with inflatable head seal Vehicle restraints Loading dock doors

11.8 The total package loading bay Further reading

Index

Xl

325 326 326 329 329 330 330 331

332

Contributors

David Bishop

Drew Britt

Michael Carr

Nicholas Cox

Tony Fenton Tony Pitt

John Roper

Bev Russell

Richard Showell

Alex Thomson

Maurice Young

David Bishop Instruments Ltd, Station Road, Heathfield, East Sussex TN21 8DR, UK Retrotech Inc., 610 Fishers Run, PO Box 586, Fishers, New York 14453-0586, USA Harry Carr Ltd, Armstrong Street, Grimsby DN31 1LG, UK Stonegrove Ltd, Unit 3, Boyd Business Centre, Whitewall Road, Medway City Estate, Rochester, Kent ME24DZ, UK Dortek Ltd, St Mark Street, Hull HU8 7ED, UK J & E Hall Ltd, 6 Prospect Place, Dartford, Kent DA1 1BU, UK BT Rolatruc Ltd, Stirling Road, Slough, Berkshire SLl 4SY, UK United Cold Store Construction Group pIc, Winchester Hill, Romsey, Hampshire S051 7UT, UK Dugard Logistics Ltd, 2 Sherwood Road, Bromsgrove B603DU, UK SARA/Loading Bay Specialist Ltd, Local Board Road, Watford, Hertfordshire WD1 2JW, UK Technical Centre, Frigoscandia Food Services, Scania House, Amwell Street, Hoddesdon, Hertfordshire EN118TT, UK

Preface

The first edition of Cold and Chilled Storage Technology was prepared at a time when great changes were taking place in the industry that were hard to put into clear perspective. For example, the CFClozone layer problem was identified, the Montreal Protocol was signed and experts from many disci­plines were already proposing 'solutions' to the problems seen at the time. Not only were there the usual differences in approach to the problems, there were different understandings of the problems themselves. For in­stance, some authoritative voices were saying HCFC 22 was 'part of the solution, not part of the problem' and recommending it as the main refrig­erant for the future, others said the opposite.

As editor, I have taken the view that this should be a 'reference book' and, as such, it should contain information that points in the direction of tried and proven good practice. To avoid the risk of misdirecting readers, I decided that the CFC issue was too unclear to be usefully discussed in the first edition and left it out altogether. This was the main criticism of the first edition at the time of its publication but, in view of the developments since then, I stand by my decision to avoid premature comment in that instance. The matter is discussed in this edition in Chapters 4 and 7, which include summaries of other related factors, in a way that was certainly not possible in 1989.

Some of the original chapter authors felt unable to contribute to this second edition, for various reasons, so new and equally experienced authors had to be found at relatively short notice. Some chapters, therefore, have been completely rewritten to incorporate current developments and guide­lines. The other authors have taken the opportunity to up-date their chap­ters to include the latest practices, new and improved equipment now available, and changes to current regulations and standards. To all of them I express my thanks, and hope that all readers will appreciate the contribu­tions they have made to taking this edition a step further to becoming a standard reference book for our continuously changing industry.

Reflecting the changes taking place, some chapters have changed; for example, the growing requirement for larger, centralised, distribution de­pots operating with 'just-in-time' deliveries of perishable goods, rapid as­sembly of mixed orders and the phased dispatch of delivery vehicles to meet critical 'time windows' at their destinations has (or should have) concen­trated our minds on the way in which the site layout and facilities affect the overall operations. There is little sense in having the optimum order­picking system in the depot if there are time-consuming bottlenecks that

XVI PREFACE

delay the movement, or positioning, of vehicles that serve it in the areas outside the depot building. A new chapter discusses this aspect in more detail.

Finally, and on a lighter note, readers with experience of the capricious nature of low-temperature installations may wonder (as I did) how Samuel Butler was able to describe so accurately our present industry three hun­dred years ago! I found the following too late for the first edition:

'Ay me! what perils do environ The man that meddles with cold iron, What pia guy mischiefs and mishaps Do dog him still with after-claps!

For though Dame Fortune seem to smile, And leer upon him for a while, She'll after show him, in the nick Of all his glories, a dog-trick.'

Samuel Butler, 'Hudibras' Pt.1, Canto III 1612-1680

For all readers who 'meddle with cold iron' I hope this book will help to avoid at least some of the 'dog-tricks' that Dame Fortune has in her repertoire.

CVJD

Preface to the first edition

When I was asked to act as editor of this book, it was suggested that after thirty-three years in the industry I must have some friends who know what they are talking about. I hope the reader will agree that the contributors to the various chapters not only know their subjects, but also have presented summaries of their specialist knowledge in a way that interlocks into the jigsaw picture of our industry. There may well be gaps, but this is due solely to the need to keep the volume to a manageable size. The choice of what to include and what to omit was mine, and I ask the reader's understanding if some aspect is missing or inadequately covered.

The first four chapters are concerned primarily with the basic functions and operation of the various types of temperature-controlled facilities in the food distribution chain. The remaining chapters consider specific tech­nical areas and equipment that make up the unique nature of temperature­controlled warehousing and goods handling. Chapter 3 however, on Controlled Atmosphere Storage, itself includes brief information on the appropriate equipment specific to this application, whilst that on Fully Automated Cold Stores comes in the later 'equipment' chapters as it is not specific to a storage function or temperature regime.

In the selection of authors, I have drawn on those with experience in the UK, USA and continental Europe. Our industry is becoming more inte­grated in international terms and as development takes place, we are all facing similar problems and finding similar solutions. For example, this book was written during a period of great activity in the UK contracting industry when a pronounced development of the composite, multi­temperature distribution depots for the major retail chains was taking place. The impact of the new requirements of these sites is reflected in the content of the relevant chapters and is equally applicable outside the UK.

I hope that this book will be a useful summary of the current situation in our industry and that it will be a valuable reference source for its readers. Finally, I wish to record my sincere appreciation of the efforts made by old and new friends who have so generously given of their time and experience.

CVJD

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