فی دوو

مرجع دانلود فایل ,تحقیق , پروژه , پایان نامه , فایل فلش گوشی

فی دوو

مرجع دانلود فایل ,تحقیق , پروژه , پایان نامه , فایل فلش گوشی

The Impact of Learners’ Awareness of Transition Words (TWs) on Writing Cause and Effect Essays among Pre-intermediate EFL Learn

اختصاصی از فی دوو The Impact of Learners’ Awareness of Transition Words (TWs) on Writing Cause and Effect Essays among Pre-intermediate EFL Learners دانلود با لینک مستقیم و پر سرعت .

 

  1. Introduction

           Writing is a complicated process which involves a number of cognitive and metacognitive activities, for instance; brainstorming, planning, outlining, organizing, drafting, and revising Cushing Wiegle writes research that shows writers spent a lot of time planning and editing their work for both organization and content, as well as taking the audience into consideration (2002, pp.22-23). The act of writing creates an environment for the development of cognitive and organizational strategies whereby students link new concepts with familiar ones, synthesize knowledge, explore relations and implications, outline information, and strengthen conceptual frameworks (Bangert-Drowns, Hurley, &Wilkinson, 2004; Scardamalia & Bereiter, 1986). Writing is a powerful tool which embracing variety of skills. It has the ability to fill up some goals (Graham, 2006). People can use it to provide and convey information (Graham et al., 2012).

            In spite of the importance of writing, most of the teachers’ attention is to the speaking skill and many of them give little or even no attention to the writing activities. Learning to write is difficult especially for those writing in a second or a foreign language since they do not know enough about how to generate ideas for writing (Mousapour Negari, 2011). According to Darayseh (2003), teaching writing is not simply means asking students to do grammar exercises in writing or getting writing which is free from grammar, punctuation and spelling mistakes, instead, writing should support students interests and their enthusiasm to communicate with the reader, and shows how they reach to  their final writing products. Some of the challenges faced by student EFL writers include their personal first language (L1) writing background and current English language proficiency, their knowledge of and motivation around the topic and their skills in planning, drafting and revising their own writing (Harmer, 2004; Hyland, 2002).


دانلود با لینک مستقیم


The Impact of Learners’ Awareness of Transition Words (TWs) on Writing Cause and Effect Essays among Pre-intermediate EFL Learners

BP Process Safety Series LNG Fire Protection and Emergency Response A collection of booklets describing hazards and how to mana

اختصاصی از فی دوو BP Process Safety Series LNG Fire Protection and Emergency Response A collection of booklets describing hazards and how to manage them, 2007 دانلود با لینک مستقیم و پر سرعت .

151 صفحه pdf

BP Process Safety Series LNG Fire Protection and Emergency Response

A collection of booklets describing hazards and how to manage them, 2007

سرفصلها:

1. Introduction to LNG . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.1 Brief history of LNG . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.2 Basic LNG production and customer flow . . . . . . . . . . . . . . . . . . . . 1
1.3 LNG import terminal facilities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
2. LNG properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2.1 LNG composition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2.2 Cryogenics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2.3 Embrittlement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
2.4 Heat of vaporization and ‘cold burns’ . . . . . . . . . . . . . . . . . . . . . . . . 4
2.5 Density and specific gravity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2.6 Boiling point and vapour pressure . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2.7 Changing composition/weathering . . . . . . . . . . . . . . . . . . . . . . . . . . 6
2.8 LNG flammability limits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
2.9 Auto ignition temperature and ignition energy . . . . . . . . . . . . . . . . . 8
3. LNG hazards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
3.1 Vapour clouds and vapour dispersion . . . . . . . . . . . . . . . . . . . . . . . 9
3.2 Vapour cloud visibility . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
3.3 Effects of heavy rainfall on LNG . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
3.4 Flash fires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
3.5 Radiant heat hazards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
3.6 Explosion hazards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
3.7 Boiling liquid expanding vapour explosion . . . . . . . . . . . . . . . . . . . . 14
3.8 Rapid phase transformation (RPT) . . . . . . . . . . . . . . . . . . . . . . . . . . 15
3.9 Tests and experiments RPT’s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
3.10 Rollover . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
3.11 Geysering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
3.12 Personnel LNG and cryogenic hazards . . . . . . . . . . . . . . . . . . . . . . 21
4. Tanks, containment and spill control . . . . . . . . . . . . . . . . . . . . . 23
4.1 Tanks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
4.2 Aboveground tanks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
4.3 LNG tank types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
4.4 Tank instrumentation and alarms . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
4.5 Internal pumps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
4.6 Power supply to pumps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
4.7 Leakages into annular space/roof space . . . . . . . . . . . . . . . . . . . . . 27
4.8 Underground storage tank . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
4.9 Insulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
4.10 LNG vaporizer units . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
4.11 Open Rack Vaporizer (ORV) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
4.12 Submerged Combustion Vaporizer (SCV) . . . . . . . . . . . . . . . . . . . . 30
4.13 Spill control—impoundment/containment . . . . . . . . . . . . . . . . . . . . . 31
4.14 Spill control objectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
4.15 Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
4.16 LNG plant basic safety measures . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
4.17 Potential leaks and spills . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
4.18 Potential releases—cryogenic issues . . . . . . . . . . . . . . . . . . . . . . . . 41
4.19 Tankage and thermal radiation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
5. Jetties and marine facilities . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
5.1 Jetties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
5.2 Marine LNG tankers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
5.3 LNG carrier cargo tanks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
5.4 Cargo tank pressure control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
5.5 Pressure, temperature and gas monitoring . . . . . . . . . . . . . . . . . . . 49
5.6 Gas dangerous zones . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
5.7 Emergency shutdown systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
5.8 Hard-arms and Power Emergency Release Couplers (PERC) . . . . 52
5.9 Firefighting systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
5.10 Manifold and valves area . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
5.11 Atmosphere control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
5.12 Cargo transfer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
5.13 Pre-arrival checks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56
6. Passive fire protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
6.1 PFP capabilities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
6.2 PFP ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
6.3 Cryogenic and fire testing of PFP . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
6.4 Typical applications of passive fire protection . . . . . . . . . . . . . . . . . 61
6.5 Design considerations—all types of PFP . . . . . . . . . . . . . . . . . . . . . 61
6.6 Intumescent materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62
6.7 Cementitious materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62
6.8 Ceramic and mineral wool fibres . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
6.9 Foamglass blocks for radiant heat reduction . . . . . . . . . . . . . . . . . . 64
7. LNG, gas and fire detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66
7.1 Cryogenics liquid detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66
7.2 Gas detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66
7.3 Fire detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
7.4 Recent incident experience . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72
7.5 Heat detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72
7.6 Flame detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72
8. Spill and fire control measures . . . . . . . . . . . . . . . . . . . . . . . . . 76
8.1 Foam for LNG vaporization reduction . . . . . . . . . . . . . . . . . . . . . . . . 76
8.2 LNG vapour reduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82
8.3 LNG fire control and radiation reduction . . . . . . . . . . . . . . . . . . . . . . 84
8.4 Extinguishment of LNG fires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86
9. Emergency response plans . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94
9.1 Scenario-specific emergency response plans . . . . . . . . . . . . . . . . . 94
10. Personal protective equipment (PPE) . . . . . . . . . . . . . . . . . . . . 98
10.1 Plant operators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98
10.2 Breathing apparatus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98
10.3 Responder personal protective equipment (PPE) . . . . . . . . . . . . . . 99
11. Codes and standards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101
11.1 Construction and operation of LNG facilities . . . . . . . . . . . . . . . . . . 101
11.2 Fire protection codes and standards . . . . . . . . . . . . . . . . . . . . . . . . 103
12. References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 104
Acronyms and abbreviations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106
Appendices:
A. Gas detection test work analysis . . . . . . . . . . . . . . . . . . . . . . . . 108
B. Foam system design considerations . . . . . . . . . . . . . . . . . . . . . . 111
C. Historical foam application data . . . . . . . . . . . . . . . . . . . . . . . . 115
D. LNG incidents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121
D.1 The Cleveland fire . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121
D.2 Staten Island, New York, February 1973 . . . . . . . . . . . . . . . . . . . . . 124
D.3 Cove Point, Maryland, October 1979 . . . . . . . . . . . . . . . . . . . . . . . . 124
D.4 LNG incidents historical table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125
E. LNG road tanker incidents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128
E.1 Nevada, USA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128
E.2 Catalonia, Spain . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129
E.3 Wales, UK . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132
F. LNG ship pre-arrival checks . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133
G. LNG ship/shore safety checklist . . . . . . . . . . . . . . . . . . . . . . . . . 137
H. Repeat checks during cargo operations . . . . . . . . . . . . . . . . . . . 144


دانلود با لینک مستقیم


BP Process Safety Series LNG Fire Protection and Emergency Response A collection of booklets describing hazards and how to manage them, 2007