E-raamat: Handbook of Explosion Prevention and Protection

Preface		xv
List of Contributors		xvii
Explosion Processes		1	(60)
Introduction		1	(13)
Quantitative Description of Combustion Processes		2	(3)
Ignition		5	(1)
Thermal Ignition		5	(5)
Chain Explosion -- Chain Reactions		10	(2)
Ignition Temperature		12	(1)
Ignition Delay Times		13	(1)
Propagation of Combustion Processes in the Gas Phase		14	(24)
Flames in Premixed Gases		15	(7)
Flame Temperature		22	(1)
Reaction Zone		23	(2)
Interaction of Flames with a Wall		25	(1)
Description of Detonations and Shock Waves		26	(8)
Limits of Detonability		34	(2)
Spherical Detonations		36	(2)
Instationary Flame Propagation: Explosions		38	(17)
Flames in Tubes: Open Systems		38	(6)
Flames in Closed Systems		44	(1)
Influence of Obstacles in the Flame Path		45	(8)
Direct Transition to Detonation		53	(2)
Explosions in the Open		55	(6)
Combustion of a Gas Cloud: An Idealized Model		56	(1)
Effect of Obstacles: Analysis of Accidents		57	(4)
Ignition Processes		61	(210)
Electrical Ignition Sources		61	(35)
Introduction		61	(1)
Ignition Process in Explosible Atmospheres		61	(4)
Minimum Ignition Energy of Flammable Gases and Vapors		65	(1)
The Concept of Minimum Ignition Energy		65	(1)
Determination Methods		65	(3)
Minimum Ignition Energies		68	(3)
Peculiarities of Hardly Flammable Vapors		71	(1)
Determination of the Minimum Ignition Energy by Laser Breakthrough		72	(1)
Energy Turnover in Sparks		73	(3)
Minimum Ignition Energy of Flammable Dusts		76	(1)
Determination Methods		76	(4)
Influence of an Inductance in the Discharge Circuit		80	(1)
Sparks on Opening and Closing Electrical Circuits		81	(1)
Introduction		81	(1)
Spark Test Apparatus		82	(1)
Limiting Values for Ignition in Capacitive, Inductive, and Ohmic Circuits		83	(2)
Explosion Prevention and Protection for Electrical Equipment		85	(2)
Compensating Electric Currents (Stray Currents) in Plants		87	(2)
Unintended Reception of High-Frequency Radiation		89	(1)
Structures in Plants Capable of Reception		89	(2)
Limiting Values for Ignition		91	(2)
Assessment of the Ignition Hazard and Prevention Measures		93	(3)
Ignition Hazards due to Static Electricity*		96	(57)
Fundamentals		96	(1)
Sytematic Approach for Judging Ignition Hazards due to Electrostatic Charging		97	(3)
Discharges in Gases		100	(2)
Different Types of Discharge		102	(1)
Spark Discharges		103	(4)
Corona Discharge		107	(1)
Brush Discharges		108	(5)
Propagating Brush Discharges		113	(5)
Discharges from Conical Piles of Bulk Goods		118	(3)
Lightning like Discharges		121	(1)
Charging of Solid Materials		122	(1)
Charging of Liquids		123	(1)
Charge Relaxation in Nonpolar Liquids		123	(4)
Ignition Hazards during Filling of Tanks		127	(9)
Stirring of Two-Phase Mixtures		136	(1)
Spraying of Liquids, Tank Cleaning		137	(4)
Charging during Handling of Gases		141	(1)
General		141	(1)
Fire Extinguishers		142	(1)
Inerting		142	(1)
Tank Cleaning with Steam		142	(1)
Unintended Release of Compressed Gases		142	(1)
Electrostatic Spraying Procedures		143	(1)
Spray Coating with Liquid Paint, Powders, or Flocks		143	(1)
Hand-Held Spraying Devices for Flammable Spraying Material		143	(2)
Stationary Electrostatic Spraying Plants for Inflammable Spray Materials		145	(1)
Electrostatic Devices for Spraying Nonflammable Materials		146	(1)
Charging of Dusts and Bulk Goods		147	(1)
The Charging Process		147	(1)
Flammable Dusts and Bulk Goods in the Absence of Flammable Gases and Vapors		148	(3)
Flammable Dusts and Bulk Goods together with Inflammable Gases and Vapors		151	(1)
Special Dusts and Bulk Goods		152	(1)
Ignition by Hot Surfaces		153	(25)
Introduction		153	(1)
Ignition Process on Hot Surfaces		153	(6)
Important Parameters		159	(1)
Type of Fuel and Explosive Mixture		159	(6)
Surface Geometry and Flow Pattern		165	(4)
Material of the Hot Surface		169	(1)
Pressure		170	(3)
Standards for Ignition Temperature Determinations, Some Safety Considerations		173	(5)
Mechanically Generated Sparks		178	(22)
Introduction		178	(2)
Impact Sparks		180	(1)
Grinding Sparks		181	(1)
Ignition Mechanisms		182	(1)
Particle Size and Shape		182	(2)
Particle Structure		184	(2)
Caloric Parameters		186	(5)
Ignition Capability, Ignitability, and Ignition Effectiveness		191	(3)
Ignition Experiments		194	(5)
Final Remarks		199	(1)
Adiabatic Compression -- Shock Waves		200	(20)
Compression		200	(2)
Compression Machines		202	(1)
Reactions		203	(1)
Two-Stage Ignition		203	(7)
Cool Flames and Two-Stage Ignition		210	(1)
Low-Temperature Hydrocarbon Oxidation		211	(2)
Shock Waves		213	(1)
Ignition at Higher Temperatures		214	(6)
Absorption of Optical Radiation		220	(7)
Introduction		220	(1)
Ignition Mechanisms		221	(1)
Resonant Absorption of Radiation in the Explosive Mixture		221	(1)
Ignition due to Plasma Formation under Focused Laser Radiation (Breakdown)		222	(1)
Absorption of Radiation by a Solid		223	(3)
Present State of Directives and Standards		226	(1)
Self-Ignition of Solid Materials (Including Dusts)		227	(29)
Fundamentals		227	(1)
The Steady-State Theory of Thermal Explosions		228	(6)
The Nonsteady-State Computation of Temperature Fields		234	(6)
Special Case: Adiabatic Induction Period		240	(4)
Experimental Practice		244	(4)
Influencing Parameters		248	(3)
SIT and Technical Regulations		251	(3)
Conclusions and Outlook		254	(2)
Chemical Reactions		256	(15)
One-Component Systems		257	(1)
Decomposition		257	(2)
Polymerization		259	(1)
Regulations for Usage and Transport		260	(1)
Multicomponent Systems		261	(1)
Oxidation with Air		262	(1)
Strong Oxidants		263	(2)
Calcium Carbide and Acetylene		265	(1)
Metal Phosphides and Phosphine		266	(2)
Pyrite (Iron Disulfide)		268	(1)
Direct Reduced Iron (DRI)		269	(1)
Regulations for Handling and Transport		270	(1)
Properties of Reactive Gases and Vapours (Safety Characteristics)		271	(108)
Safety Characteristics of Gases and Vapors		271	(52)
Introduction		271	(1)
Determination and Use of Safety Characteristics		271	(1)
Stating Numerical Values of SCs		272	(1)
Calculation and Estimation of SCs		272	(1)
Use of SCs		273	(1)
Classification of SCs		273	(1)
Tables and Data Bases for SCs		274	(1)
SCs in Regulations and Standards		275	(1)
SCs for Characterizing the Explosibility of Substances (Mixtures of Substances)		275	(1)
Explosion Limits		276	(6)
Further Characteristics of Explosion Regions		282	(5)
Temperature and Pressure Limits for Instability		287	(6)
Explosion Points		293	(1)
Flash Point		294	(3)
SCs for Assessing the Ignitability of Substances (Mixtures)		297	(1)
Minimum Ignition Energy, Minimum Ignition Current, Minimum Ignition Current Ratio		297	(4)
Autoignition Temperature (AIT)		301	(3)
SCs for the Assessment of the Propagation of the Reaction		304	(1)
Detonation Limits		304	(3)
Propagation Velocity of Deflagrations (``lame Velocity'')		307	(4)
Maximum Experimental Safe Gap		311	(3)
SCs for Assessing the Effects of an Explosion		314	(1)
Explosion Pressure and Maximum Explosion Pressure		314	(5)
Rate of Pressure Rise and Maximum Rate of Pressure Rise, ``KG value''`		319	(2)
Pressure Effect of Detonations		321	(1)
Other Chemical and Physical Substance Characteristics Which are Important for Assessments in Safety Technnology		322	(1)
Safety Characteristics and Properties of Gases and Vapors: a Physicochemical Approach		323	(56)
Introduction		323	(1)
Summary of Fundamentals		324	(1)
Physical Properties of Gases		324	(1)
Phase Equilibria of Pure Substances and Mixtures		325	(2)
Chemical Equilibrium		327	(1)
Chemical Kinetics		328	(3)
Transport Processes		331	(2)
Combustion: List of References		333	(1)
Flames: Reactions at High Temperature		334	(1)
Introduction		334	(2)
Reaction Mechanism and Flame Velocity		336	(7)
Inhibitors/Promoters		343	(2)
Limits of Flammability		345	(6)
Flame Velocity and Ignition, Minimum Ignition Energy, Quenching Distance		351	(3)
Oxidation at Low Temperature		354	(1)
Some Experimental Findings		354	(5)
Chain Explosion		359	(11)
Thermal Explosion		370	(9)
Properties of Combustible Dusts (Safety Characteristics)		379	(40)
Introduction		379	(2)
Dust Deposits (Burning Characteristics)		381	(10)
Combustion Behaviour		381	(1)
Minimum Ignition Temperature of a Dust Layer on a Hot Surface (MITlayer)		382	(2)
Self-Ignition Behavior of Dust Piles		384	(3)
Capability to Deflagrate		387	(1)
Impact Sensitivity		388	(1)
Characteristics of Pyrolysis Gases Generated by Dust Piles under Thermal Stress		389	(2)
Suspended Dusts (Explosion Characteristics)		391	(28)
Maximum Explosion Pressure and Maximum Rate of Pressure Rise of Dust Explosions		392	(5)
Influence of Different Initial Conditions		397	(3)
Problems with Transfer to Practical Plant Conditions		400	(2)
Laminar Burning Velocity		402	(3)
Lower Explosion Limit		405	(4)
Limiting Oxygen Concentration		409	(2)
Minimum Ignition Temperature of the Dust Cloud in a Hot Furnace (MIT0cloud)		411	(4)
Minimum Ignition Energy of a Dust Cloud		415	(4)
Properties of Flammable Mists and Foams		419	(62)
Flammable Mists and Spray Jets		419	(26)
Introduction		419	(1)
Definitions		419	(2)
Hazards in Practical Applications		421	(1)
Generation of Mists and Spray Jets		421	(1)
Special Physical Features		421	(1)
Methods of Generation in Practice		422	(1)
Characterization of Mists and Sprays		423	(1)
Degree of Dispersion		423	(2)
Concentration		425	(1)
Relative Motion of the Phases		426	(1)
Combustion in Mists and Spray Jets		426	(1)
Fundamentals		426	(3)
Lower Explosion Limit		429	(3)
Flame Propagation Velocities		432	(1)
Detonation Processes		433	(1)
Effectiveness of Ignition Sources		434	(5)
Maximum Explosion Pressure		439	(2)
Rate of Explosion Pressure Rise		441	(1)
Fire Hazard Classification		442	(1)
Maximum Experimental Safe Gap		442	(1)
Prevention and Protection Measures		443	(1)
Avoidance of Explosible Droplet Suspensions		443	(1)
Avoidance of Ignition Sources		443	(1)
Mitigation of the Effects of Fires and Explosions		444	(1)
Heterogeneous Systems Consisting of Organic Liquids and Oxygen		445	(36)
Introduction		445	(2)
Wick Detonations		447	(3)
Bubble Explosions		450	(1)
Bubble Explosions Ignited by Shock Waves or Detonation Waves		450	(1)
Bubble Explosions Ignited by an Incandescent Wire		451	(2)
Foam Detonations		453	(2)
Detonations of Model Foams		455	(1)
Detonation Ranges of Model Foams		455	(1)
Detonation Velocity of Model Foams		456	(4)
Run-up Distances of Detonations in Model Foams		460	(1)
Detonation Pressures in Model Foams		460	(1)
Semi-Empirical Model of Foam Detonations		460	(1)
Cyclohexane Foams as Examples of Real Foams		461	(3)
Surface Detonations		464	(1)
One-Dimensional Surface Detonations		464	(7)
Two-Dimensional Surface Detonations		471	(8)
Final Considerations		479	(1)
Safety Concept		479	(1)
Safety Characteristics		480	(1)
Measures of Explosion Protection and Prevention		481	(130)
Course of the Explosion Pressure in Closed Vessels and Their Design		481	(12)
Deflagrations in Closed Spaces		482	(1)
Pressure--Time Course		482	(3)
Maximum Temporal Pressure Increase of Deflagrations		485	(1)
Maximum Pressure of Deflagrations		486	(3)
Detonations		489	(2)
Wall Loading due to Gas Explosions		491	(2)
Explosion Venting		493	(38)
Introduction		493	(1)
Introductory Remark		493	(1)
Principle of the Protection Measure		494	(1)
Importance of the Protection Measure		495	(2)
Methods for Determining the Necessary Vent Area		497	(1)
Introduction		497	(1)
Single-Step Methods		497	(3)
Principal Assumptions and Preconditions for the One-Step Methods		500	(1)
Disadvantages of the Single-Step Methods		501	(1)
Methods Based on Models		502	(1)
Physical Background		503	(1)
Course of Pressure with Time		503	(5)
Quantities Influencing Pred and (dp/dt)red		508	(9)
Effects in the Surrounding Region		517	(2)
Recoil		519	(1)
Pipes		519	(1)
Types of Venting Devices		520	(1)
Introduction		520	(1)
Devices with Nonreusable Elements		521	(3)
Devices with Reusable Elements		524	(1)
Special Devices		525	(2)
Regulations		527	(1)
VDI Guideline 3673		527	(1)
NFPA Guideline 68		527	(1)
AFNOR Standard U 54-540		528	(1)
European Pre-Standard (prEN 14491) on the Dimensioning of Venting Systems for Dust Explosions		528	(1)
Draft of a European Standard on the Requirements for the Design and Construction of Venting Devices		529	(1)
Future Developments		529	(1)
Enclosures with Thin Walls		529	(1)
Venting of gas explosions		529	(1)
Venting in the Presence of Obstacles to Flow		530	(1)
Venting of Connected Vessels		530	(1)
Final Remark		530	(1)
Explosion Suppression		531	(29)
Introduction		531	(1)
Definition		531	(1)
Description of the Suppression System		532	(1)
Detectors/Sensors		532	(4)
HRD Suppressors		536	(5)
Suppressants		541	(3)
Control and Indicating Equipment (CIE)		544	(1)
Theory of Explosion Suppression		545	(1)
Design of Explosion Suppression Systems		546	(1)
General		546	(1)
Hazard Definition		547	(2)
Design for Vessels with L/D < 2 (Compact Vessels)		549	(1)
Design for Vessels with 2 ≤ L/D ≤ 10 (Elongated Vessels)		550	(1)
Computer-Aided Design		551	(1)
Application Limits of Suppression Systems		552	(1)
Example of Applications		553	(4)
Final Consideration		557	(3)
Explosion Isolation		560	(23)
Introduction		560	(1)
Isolation Systems		561	(1)
Rotary Air Lock		561	(1)
Extinguishing Barrier		562	(2)
Explosion Protection Sliding Valve		564	(1)
Explosion Protection Float Valve		565	(2)
Diverter		567	(2)
Double-Slide System		569	(1)
Product Layer		569	(1)
Screw Conveyer as a Choke		570	(1)
Extinguishing Barriers in Combination with a Diverter		571	(1)
Design Basics		571	(1)
Base Parameters		571	(1)
Choice of Detector/Sensor		572	(2)
Installation Distance		574	(2)
Quantity of Suppressant Ms for Extinguishing Barriers		576	(2)
Diverter		578	(1)
Examples of Applications		578	(4)
Final Remark		582	(1)
Flame Arresters		583	(28)
Introduction		583	(1)
Fundamental Principles		584	(1)
Flame Quenching in Narrow Gaps		584	(2)
Arresting of Flames by Hydraulic Arresters		586	(1)
Arresting of Flames by an Opposed High-Velocity Flow		587	(1)
Preventing Flame Transmission by Liquid Barriers		588	(1)
Specific Types of Loads and Classifications		588	(1)
Deflagrations		588	(1)
Detonations		589	(3)
Stabilized Burning		592	(1)
Examples for Design and Construction of the Main Types of Flame Arresters		592	(1)
Static Flame Arresters		592	(4)
Flame Arresters with Wet Arresting Elements		596	(2)
Flame Arresters Using a High-Velocity Flow		598	(1)
Process Engineering Equipment		599	(1)
Detection of Stabilized Flames		599	(1)
Devices Resistant to Endurance Burning		600	(1)
Measuring and Control Equipment for Hydraulic Arresters		600	(1)
Measuring Equipment at Flow-Controlled Apertures for Burner Injection		600	(1)
Measures to Ensure Functionality		601	(1)
Tests		602	(1)
Mechanical Stability		602	(1)
Tightness		602	(1)
Pressure Drop of the Flowing Medium		602	(1)
Flame-Arresting Effect		603	(2)
Conditions of Use		605	(1)
Explosion Groups of Gases and Vapors		606	(1)
Pressure and Temperature of the Mixtures		606	(1)
Configuration of Pipework		606	(2)
Special Problems of Safe Operation		608	(1)
Examples of Application in Practice		608	(1)
Safeguarding of a Tank for Flammable Liquids		608	(1)
Safeguarding of a Thermal Postcombustion Plant		609	(2)
Fundamentals of Understanding and Judging Explosion Risks		611	(30)
Basic Terms in Safety Engineering		612	(5)
Explosions Risks		617	(24)
The Principle of Probabilities		617	(2)
Primary Explosion Protection		619	(1)
General		619	(2)
Ventilation		621	(3)
Inertization of Explosive Mixtures		624	(2)
Gas Detectors		626	(1)
Secondary Explosion Protection		627	(1)
Fundamentals		627	(3)
Type and Extent of Explosion-Hazard Areas (Zones)		630	(2)
Protection against Ignition Hazards		632	(2)
Protection against Explosion Effects in the Explosion-Hazard Areas		634	(2)
Regulations on Explosion Protection in Explosion-Hazard Areas		636	(2)
Protection against Explosion Damages in Remote Areas		638	(1)
Procedures for Investigating and Describing Explosion Risks		638	(3)
References		641	(48)
Index		689

Dr. Martin Hattwig studied chemistry at the University of Gottingen. In 1966, he obtained his doctor's degree at the Institute of Physical Chemistry with a thesis on the one-stage cool flame of methyl-ethyl-ether. From 1966 on, he worked at the Federal Institute for Research and Testing Materials (BAM) as a scientific collaborator of Prof. Heinrich, and became head of the laboratory "Explosion dynamics" in 1969. His main fields of activity were the venting of explosions, detonations of gaseous systems, and safe handling of degreasing solvents. Since 1989 he also participated extensively in European standardization and legislation concerning explosion safety. From 1983 to 2001 he was head of the division "Heterogeneous Combustion Reactions" at BAM. Dr.-Ing. Henrikus Steen studied Thermodynamics and Chemical Engineering at the Technical University of Braunschweig. From 1965, he worked as scientific collaborator of Karl Nabert and Prof. Gerhard Schon at the Physikalisch-Technische Bundesanstalt (PTB), Braunschweig. He occupied himself with all problems of safety techniques, especially with explosion prevention and protection when handling flammable liquids. 1973 he obtained his doctor's degree from the Technische Hochschule Aachen with a thesis on the vaporization in spray jets. Also in 1973, he became head of laboratory "Flammable Liquids" at the PTB. In 1980, he became head of the division "Fundamentals of Physical Safety techniques" at the PTB, and from 1989 to 1995, he headed the Department "Chemical Safety Techniques" at the Federal Institute of Materials Research and Testing (BAM), Berlin.