Plant Engineer's Reference Book

737 Pages·1991·26.128 MB·English

by  Dennis A. Snow (Eds.)

Plant Engineer's
Reference Book
Edited by
Eur ing Dennis A. Snow
CEng, MIMechE, HonFIPIantE, HonFIIPE
Teaching Fellow, Loughborough University of
Technology, UK; Senior Lecturer,
Leicester Polytechnic, UK
FHlJ T T E R W O R TH
Η Ε I Ν Ε Μ Α Ν Ν
Butterworth-Heinemann Ltd
Linacre House, Jordan Hill, Oxford OX2 8DP
^» PART OF REED INTERNATIONAL BOOKS
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TOKYO TORONTO WELLINGTON
First published 1991
© Butterworth-Heinemann Ltd 1991
All rights reserved. No part of this publication may be reproduced in any material
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of a licence issued by the Copyright Licensing Agency Ltd, 90 Tottenham Court
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written permission to reproduce any part of this publication should be addressed
to the publishers.
British Library Cataloguing in Publication Data
Plant engineer's reference book.
1. Engineering plants
I. Snow, Dennis A.
620
ISBN 0 7506 1015 8
Library of Congress Cataloging-in-Publication Data
Plant engineer's reference book /edited by Dennis A Snow.
p. cm.
Includes bibliographical references and index.
ISBN 0 7506 1015 8
1. Plant engineering—Handbooks, manuals,
etc. I. Snow, Dennis A.
TS184.P58 1991
696-<lc20 90-2105
CIP
Filmset by Mid-County Press, Salisbury
Printed and bound in Great Britain by Hartnolls Ltd,
Bodmin, Cornwall
Foreword
The opportunity to write the foreword to a new book falls to
very few people and I consider myself very fortunate to be able
to introduce you to the Plant Engineer's Reference Book.
It has been many years since a book was written specifically
for the engineer who is involved with so many facets of the
engineering profession, and I am of the firm opinion that this
publication is long overdue.
The many chapters covering the multidisciplinary role of the
plant engineer have been written by practising experts and
specialists, and the whole has been edited by Dennis Snow, a
plant engineer of international reputation.
This reference book is so written as to take the reader through
the design, planning, installing, commissioning and operating
stages of both major and minor engineering projects. It covers
all aspects of maintenance, management, health and safety, and
finance and gives a guide to where further information on these
subjects may be obtained.
It is a book which should be in the hands of all practising
plant engineers and senior management who are involved in the
efficient running and control of their respective establishments.
As a plant engineer of many years' experience, I recommend
this book to you as the definitive Reference Book for all members
of our profession.
Richard J Wyatt
President, The Institution of Plant Engineers
Preface
The preparation of a reference book such as this could not APV Baker Ltd
possibly be acheived without the total cooperation of so many The Boots Company pic
individual authors and the backing of their various employers, BP Oil (UK) Ltd
especially where company contributions have been made, British Coal
bringing together a wealth of professional knowledge and British Gas
experience. British Compressed Air Society
An acknowledgement such as this can only scratch the surface Colt International Ltd
and cannot really portray the grateful thanks I wish to Cortest Laboratories Ltd
acknowledge to all these people and concerns who have devoted Davy McKee (Stockton) Ltd
so much time and effort to place their ideas and contributions Film Cooling Towers Limited
on paper. Heaton Energy Services
Plant Engineering is such a broad subject incorporating a The Institution of Plant Engineers
multitude of disciplines and a wide variety of solutions to I Ô I Anti-Corrosion Ltd
virtually every problem or situation, unlike some subjects that Liquefied Petroleum Gas Industry Technical Association
have clear cut methods. Loughborough University of Technology
In compiling the initial suggested guidelines for each of the National Vulcan Engineering Insurance Group Ltd
contributions, I posed the questions to myself for what Ove Arup & Partners, Industrial Division
information and assistance had I found difficult to locate during Pilkington Insulation Ltd
over 30 years in industry as a Plant Engineer responsible for Royal Insurance (UK) Ltd
plant in the UK and abroad and how could it be best presented SBD Construction Products Limited
to assist others in their profession. Saacke Ltd
As an active member of the Institution of Plant Engineers for Senior Green Limited
many years I have been able to seek the knowledge of my Spirax-Sarco Limited
colleagues when problems have occurred and I hope that I have Support Services
been able to help them on occasions. Taylor Associates
I would therefore like to take this opportunity to thank those Thorn Lighting
members of the Institution for their patience and assistance in
helping me to structure this publication, and in particular, I would also like to include my wife Betty, who has been
members of the Publication Committee, together with the extremely tolerant whilst I have spent many hours word
following companies: processing.
ABB Power Ltd
W S Atkins Consultants Ltd
J Â Auger (Midlands) Ltd Dennis A Snow
List of
Contributors
A Armer S McGrory
Spirax Sarco Ltd BP Oil UK Ltd
Β Augur, IEng, FIPlantE, MBES R J Neller
J Â Augur (Midlands) Ltd Film Cooling Towers Ltd
Η Barber, BSc Ove Arup & Partners, Industrial Division
Loughborough University of Technology G Pitblado, IEng, MIPlantE, DipSM
Support Services
D A Baylis, FICorrST, FTSC
R S Pratt, ALU, CEng, MIMfgE, MBIM, MSAE
J Bevan, IEng, MIPlantE
Secretary-General, The Institution of Plant Engineers
R J Blaen
G Å Pritchard, CEng, FCIBSE, FInstE, FIPlantE, MASHRAE
Senior Green Limited
British Compressed Air Society Risk Control Unit
Royal Insurance (UK) Ltd
Eur Ing G Burbage-Atter, BSc, CEng, FInstE, HonFIPlantE,
FCIBSE R Robinson, BSc, CEng, FIEE
Heaton Energy Services The Boots Co. pic
Ρ D Compton, BSc, CEng, MCIBSE M J Schofield, BSc, MSc, PhD, MICorrT
Colt International Ltd Cortest Laboratories Ltd
IG Crow, BEng, PhD, CEng, FIMechE, FIMarE, MemASME J D Ν Shaw, MA
Davy McKee (Stockton) Ltd SBD Construction Products Ltd
Ρ Fleming, BSc(Eng), ARSM, CEng, MInstE R H Shipman, MIMechE, MIGasE, MInstE
British Gas pic Liquefied Petroleum Gas Industry Association
C Foster Κ Shippen, BSc, CEng, MIMechE
British Coal ABB Power Ltd
C French, CEng, FInstE, FBIM G Solt, FIChemE, FRSC
Saacke Ltd Cranfield Institute of Technology
F Τ Gallyer Κ Taylor, CEng, FCIBSE, FIPlantE, FIHospE, FSE, FIOP,
Pilkington Insulation Ltd MASHRAE, FBIM, ACIArb
Eur Ing R R Gibson, BTech, MSc, CEng, FIMechE, FIMarE, Taylor Associates Ltd
FRSA L W Turrell, FCA
W S Atkins Consultants Ltd
Κ Turton, BSc(Eng), CEng, MIMechE
Β Holmes, BSc(Tech), PhD, CEng, FIChemE, FInstE Loughborough University of Technology
W S Atkins Consultants Ltd
Å Walker, BSc, CEng, MIMechE
A Ρ Hyde Senior Green Limited
National Vulcan Engineering Insurance Group Ltd
R C Webster, BSc, MIEH
Η King Environmental Consultant
Thorn Lighting
Β R Lamb, CEng, MIChemE D Whittleton, MA, CEng, MIMechE, MHKIE
APV Baker Ltd Ove Arup & Partners, Industrial Division
1A/1
Physical
1A
Considerations in
Site Selection
Contents
1 A.Î Environmental considerations of valley or hillside
sites 1 A/3
1 A.l .1 The effect of topography on prevailing winds and
strengths 1 A3
1A.1.2 Design for wind 1A/4
1A.1.3 The factored basic wind speed approach 1A./4
1A.2 Road, rail, sea and air access to industrial sites 1A/4
1A.2.1 Introduction 1A/4
1A.2.2 Design considerations 1 A/5
1A.2.3 Forms of site access IA 5
I A.2.4 Providing access to the road system I A/5
1A.2.5 Selection of sites Î A, 5
1A.2.6 Checklist 1A 6
I A.3 Discharge of effluent and general site drainage 1A.6
1A.3.1 Effluent 1A/6
1A.3.2 Site drainage 1A/7
1A.4 Natural water supplies, water authority suppliers
and the appropriate negotiating methods and
contracts 1A/8
1A.5 Water storage, settling wells and draw-off
regulations 1 A. 14
1A.5.1 Water storage 1A 14
1A.5.2 Draw-offs 1A 15
1A.6 Problem areas associated with on-site sewage
treatment for isolated areas IA 16
1A.6.1 Cesspools 1 A/16
1A.6.2 Septic tanks 1 A/17
A.7 Landscaping on industrial and reclaimed land 1A,17
1A.7.1 General 1A/17
1A.7.2 Contaminated land 1A/17
1A.7.3 Non-contaminated land 1A/19
Environmental considerations of valley or hillside sites 1A/3
1A.1 Environmental considerations and dissipating at the downward edge as the air falls
of valley or hillside sites again.
Conditions are frequently suitable for the formation of
1A1.1 The effect of topography on prevailing lee waves over the UK, an effect that is routinely exploited
winds and strengths by glider pilots to obtain exceptionally high altitudes.
The combination of lee waves with strong wind, sufficient
Apart from the obvious influence of topography in
to produce damage to structures in the bands of
producing shelter or the enhanced exposure to wind
accelerated flow, is fortunately rare, but an analysis of
(discussed later), the influence of large topographic
the Sheffield gale of 16 February 1962 by the UK
features can be sufficient to generate small-scale weather
systems which are capable of producing significant winds. Meteorological Office showed that this was a case where
Three types of wind are associated with topography: strong winds were further enhanced by lee waves.
Diurnal winds
Gravity winds
Lee waves
Other factors
Other factors to account for topography with regard to
Diurnal winds
valley or hillside sites should include possible inversion
Under clear skies in daytime the slopes of hills and and failure to disperse pollutants. Temperature inversion
mountains facing the sun will receive greater solar heating occurs when the temperature at a certain layer of the
than the flat ground in valley bottoms. Convection then atmosphere stays constant, or even increases with height,
causes an upslope flow, called anabatic wind, which is as opposed to decreasing with height, which is the norm
generally light and variable but which can often initiate for the lower atmosphere. Inversions may occur on still,
thunderstorms. At night, the upper slopes lose heat by clear nights when the earth and adjacent air cool more
radiation faster than the lower slopes and the reverse rapidly than the free atmosphere, or when throughout a
effect happens, producing downslope katabatic winds. layer high turbulence causes rapid vertical convection so
However, the denser cold air falling into the warmer that the top of the turbulent layer may be cooler than
valley can produce strong winds in a layer near the the next layer above it at the interface.
ground. The higher the mountains, the stronger is the The running of a cool air flow under a warm wind
effect. As the mountains in the UK are not very high, it is another cause of temperature inversion. As a rule,
is not surprising that the speeds of katabatic winds do the presence of an inversion implies a highly stable
not approach those of large depressions. atmosphere: one in which vertical air movements are
rapidly damped out. In such a situation, fog and airborne
pollutants collect, being unable to move freely or be
Gravity winds
dissipated by convection.
The effect of katabatic winds can be much enhanced if Additional dispersal problems may occur when the
greater differences in air temperature can be obtained prevailing wind occurs perpendicular (or nearly so) to
from external sources. A continuous range of mountains the valley or hill ridge line. This may lead to speed up
can act as a barrier to the passage of a dense mass of and turbulence over the valley or it may simply reduce
cold air as it attempts to displace a warmer air mass. the effect of airflow carrying away airborne pollutants.
Cold air accumulates behind the mountain range until It is possible to obtain wind data for almost any
it is able to pour over the top, accelerating under gravity location in the world, although these frequently require
to give strong winds down the lee slope. The mountains modification and interpretation before they can be used.
of the UK are not high enough to produce gravity winds Addresses of advisory offices for the UK are listed below.
of speeds sufficient to damage buildings.
Lee waves
Advisory offices of the Meteorological Office
Under certain conditions of atmospheric stability, stand-
ing waves may form in the lee of mountains. This wave For England and Wales:
motion is an oscillating exchange of kinetic and potential Meteorological Office
energy, excited by normal winds flowing over the Met 0 3
mountain range, which produces alternately accelerated London Road
and retarded flow near the ground. Sustained lee waves Bracknell
at the maximum amplitude are obtained when the shape Berkshire RG12 2SZ
of the mountain matches their wavelength, or when a Tel. [phone] (Extn 2299)
second range occurs at one wavelength downstream. The
existence of lee waves is often indicated by clouds which For Scotland:
are unusual in that they remain stationary with respect Meteorological Office
to the ground instead of moving with the wind. These 231 Corstorphine Road
clouds are continuously forming at their upwind edge as Edinburgh EH 12 7BB
the air rises above the condensation level in the wave Tel. [phone] (Extn 524)
1A/4 Physical considerations in site selection
For Northern Ireland: be approximated by a single straight line for more than
Meteorological Office two-thirds of its length, then the shape is 'sharp'.
Progressive House Otherwise the changes of slope are gradual and the shape
1 College Square East is 'smooth'. This distribution is relevant for sites close
Belfast BT1 6BQ to the foot of the upwind slope, where 'sharp' topography
Tel. [phone] offers a greater degree of shelter.
Advisory service of the Building Research 52 - Ground roughness, building size and height
Establishment above ground factors
The Advisory Service The factor S takes account of the combined effect of
2
Building Research Station ground roughness, the variation of wind speed with
Bucknalls Lane height above ground and the size of the building or
Garston component part under consideration. In conditions of
Watford WD2 7JR strong wind the wind speed usually increases with height
Tel. [phone] above ground. The rate of increase depends on ground
roughness and also on whether short gusts or mean wind
speeds are being considered. This is related to building
1A.1.2 Design for wind size to take account of the fact that small buildings and
elements of a building are more affected by short gusts
A structure may be designed to comply with any of the
than are larger buildings, for which a longer and
following information:
averaging period is more appropriate.
1. No specific details available.
2. Specified basic wind speed and relevant site data.
5 - Statistical factor
3. Specified design wind speed, with or without FOS. 3
4. Specified survival wind speed, with or without FOS. Factor S is based on statistical concepts and can be
3
varied from 1.0 to account for structures whose probable
When details are given they should be checked, if only
lives are shorter (or longer) than is reasonable for the
by comparison with equivalent wind speeds derived from
application of a 50-year return-period wind.
first principles, to ensure that they are reasonable.
Depending on the specified requirements the wind
speeds may or may not utilize gust wind speeds as in S - Directional factor
A
CP3 (3) or mean hourly wind speeds, v, with applied gust
factors. In the latitudes occupied by the UK (50-60°N) the
climate is dominated by westerly winds and a band of
low pressure between Scotland and Iceland. The basic
1A.1.3 The factored basic wind speed approach wind speed may be adjusted to ensure that the risk of it
being exceeded is the same for all directions. This is
The current British Standard Code of Practice (CP3: achieved by the wind speed factor S .
Chapter V: Part 2: 1972) uses a basic gust wind speed, 4
When applying S , topography factor S and the
K, multiplied by a series of S factors which adjust the 4 l
terrain roughness, building size and height above ground
basic values to design values for the particular situation.
factor S should be appropriately assessed for that
CP3 uses up to four S factors: 2
direction.
Si'. Topography factors
S: Ground roughness, building size and height above
2 1A.2 Road, rail, sea and air access to
ground factors
S : Statistical factor industrial sites
3
5 : Directional factor
4 1A.2.1 Introduction
Many industrial processes and factories require specific
S - Topography factors
l accessibility for one particular form of transport. Ex-
The effect of local topography is to accelerate the wind amples of the above include distribution warehousing,
near summits or crests of hills, escarpments or ridges and transport operations (particularly intermodal such as
decelerate it in valleys or near the foot of steep through seaports) and those industries dealing with bulk
escarpments or ridges. The extent of this effect on gust commodities (e.g. oil refineries). For other industries
wind speeds is generally confined to the region 1.0-1.36. access to strategic modal networks is important in order
Local topography is considered significant when the to be competitive where cost of transport and time
gradient of the upwind slope is greater than 5%. savings are a significant factor. Examples of these
The shape of the upwind slope affects the degree of operations include air freighting and fresh-food deliveries.
shelter expected near the foot of the slope when the slope A third category would include those establishments
is shallow and the flow remains attached. When the which would require high-visibility sites to enhance their
changes in slope are sudden, so that upwind slope can reputation in the marketplace.
Road, rail, sea and air access to industrial sites 1 A/5
1A.2.2 Design considerations obtain the consent of the relevant highway authority. In
England the Department of Transport is the highway
It is difficult to give specific advice on this subject as
authority for all motorways and trunk roads. Direct
there is a very large range of industrial undertakings. The
access to motorways is generally prohibited and the
awareness for, and acceptability of, access is dependent
policy regarding access to trunk roads is to minimize the
on the types of goods to be moved and the frequency
number of accesses and to encourage the free flow of
and method of movement. In some undertakings there
traffic on the major road. Therefore careful consideration
is a major movement between different transport modes
needs to be given to the ability of the proposed access
which is concentrated either at ports or at major road/rail
to cover traffic capacity and road safety adequately.
interchanges.
The local county council is the highway authority, in
In addition to the amount of commercial traffic it is
non-metropolitan areas, for all other roads, although, in
vital to consider the movement associated with employees
many instances the local authority (generally, city or
and visitors, which themselves can generate large numbers
district) may have agency powers for the roads within
of vehicular and pedestrian movements. For very large
its area.
manufacturing sites there will also be the need for
It will be necessary to forecast the amount of traffic
accessibility for public transport, which, for a large
to be generated by the development within the site and
workforce, may need to be supplemented by investment
to propose a form of junction which not only deals with
in subsidized travel.
the site's traffic but also adequately caters for the existing
Site access will reflect the nature of the existing local
traffic on the road. Tests for capacity are required and
transport system and will need to be designed to cater
attention should also be given to the safety of operation
for the anticipated future traffic flows associated with
of the proposed access.
on-site development. At the extreme of the range this
Various types of junctions are available and include
could include a significant on-site infrastructure, poten-
simple priority T-junctions, traffic signals and round-
tially involving small bus stations for staff or private
abouts. In proposing any junction improvements or new
rail sidings for goods heavily committed to using the
junction it is necessary to be aware of land ownership in
rail network. Special consideration might also need
order to ensure that all improvement works can be
to be given to customs facilities, where operations
carried out within highway land or land within the
include cross-border movements with or without bonding
proposed development site.
operations.
As part of the planning approvals it is increasingly
common to provide road-improvement schemes which
1A.2.3 Forms of site access are sometimes off-site and are necessary to deal with
site-generated traffic, which has detrimental effects on the
Access to the road network can range from a simple
local road network. These off-site improvement schemes
factory gate or location on a business park to a major
can be obtained within legal agreements referred to as
industrial complex requiring its own major grade
Section 106 Agreements. These are undertaken with the
separated interchange due to the high traffic volumes on
local planning authority or with Section 278 Agree-
the strategic road network. New site developments will
ments, undertaken directly with the highway authority.
need to cater for future traffic growth and must be
Generally, these Agreements require the applicant of the
adequate to deal with a design life over the foreseeable
proposed site to carry out specified highway improve-
future.
ment schemes to an agreed timetable relevant to the
Access to the rail system must be negotiated with
planning application.
British Rail and may involve the use of a Section 8 Grant,
In the above examples the location of the site adjacent
where it can be demonstrated that the use of the rail
to a strategic route network is an important consideration.
network minimizes lorry traffic on the road system. It
will be necessary to incorporate security arrangements
to prevent trespass on the rail line and some form of
signalling arrangement will be necessary for the junction
and sidings. Major complexes may run their own railway
1A.2.5 Selection of sites
network, including a private shunting engine.
Access to a seaport will be limited by the ability of Suitable sites are normally limited to those areas designed
total traffic generated by the docks and the incorporation in Development Plans as being for industrial or com-
of these traffic movements into the local road system. mercial uses. Such land should be capable of being
Air traffic access may be constrained by the operational accessed directly from the primary or secondary dis-
aspects of the airport. Otherwise, the road-related traffic tributor roads in the area. Segregation of lorries and lorry
will be dealt with in a manner similar to that of seaports, access from residential areas should be achieved where
except that the vehicles are likely to be smaller in size possible.
and of lower traffic volumes, reflecting the higher-value The utilization of existing or the provision of new rail
goods being transported by air. heads will also be a determining factor for some
operators, and frequently the rail sidings do not have
good road access. In these cases extensive improvement
1A.2.4 Providing access to the road system
measures may be necessary to provide adequate space
Before access is obtained to any road it is necessary to and geometrical requirements.
1A/6 Physical considerations in site selection
1A.2.6 Checklist above will lead to difficulty of operation, tyre scrub,
potential damage to vehicles and buildings, and general
The following list, while not exhaustive, identifies many
inefficiency. Cost effectiveness could also be hindered due
of the issues which will need careful consideration. In
to loss of time caused by blocked-in vehicles. Safety is
many instances it might be necessary to seek the advice
also a highly important factor which should be prominent
of a specialist traffic consultant, either in the design of a
in any decision making.
scheme or in access, or to negotiate with the highway
authority the impact of a proposed development and any
attendant road-improvement schemes.
1 A.3 Discharge of effluent and general
1. Types of operation to be carried out site drainage
• Number of lorries
• Staff cars 1A.3.1 Effluent
• Visitors' cars Introduction
• Rail/water/air access
• Public transport provision The control of drainage and sewerage systems and of
• Cyclists sewage disposal is governed entirely by Parliamentary
• Pedestrians Acts and statutory regulation. The Building Regulations
1985 and Public Health Acts 1936 and 1961 cover
2. Types of site sewerage, sewage disposal, drainage and sanitation for
• Large single site buildings and other public health matters. The Public
• Industrial estate Health Act 1937 (Drainage of Trade Premises) and the
• Segregation of access for lorries and cars Control of Pollution Act 1974 deals, among other things,
• Capacity of access and need for improvement with the disposal of trade and industrial effluent.
• Ensure no queueing back onto highway
• Ensure sufficient on-site space for all vehicles to enter
highway in forward gear Methods of treatment
• Ensure off-highway loading/unloading
Two methods of treatment can be considered:
• Access for emergency vehicles
1. On-site treatment and disposal; and
3. Access arrangements
• Junction types - priority 2. Off-site treatment and disposal.
- roundabout Where on-site treatment is to be undertaken consider-
- signals ation should be given to the following:
• Access width should be a minimum of 6.1 m to allow
lorries to pass each other (7.3 m ideal) 1. Where large volumes of effluents are produced and/or
different types of contaminants, large equipment
• Single access could cope with up to 250 lorry
areas may be required. Sufficient space must also be
movements per day
allowed for maintenance and inspection of such
• Any gate or security barrier to be set in at least 20 m
equipment.
from public highway to avoid blockage or interference
to pedestrians 2. Settlement/storage areas for effluent need to be sized
not just for average flow but also for peak periods.
• Minimum centre line radius to be 12 m
Where production is based on a shift system, peak
• Minimum entire live radius to access road to be 60 m.
flows created during holiday periods (shutdown,
Widening on bends may be required
major maintenance, etc.) should be considered.
4. Manoeuvring space
3. Where effluents require primary, secondary and pos-
• Turning circle for articulated vehicles to be 26 m
sibly additional tertiary treatment, attention should
diameter minimum
be paid to the various treatment processes with
• For draw-bar vehicles this can be reduced to 21 m
regard to personnel safety and public sensitivity to
• Turning head for rigid lorries only needs to be 35 m
on-site treatment.
long
4. Where concentrated alkali and/or acids are stored
• Turning head for articulated vehicles should be 53 m
and used on-site as part of the treatment process,
long. Kerb radii need to be 9 m
care should be exercised to prevent misuse, fire, and
• Loading bays at 90° to road should be 31 m deep
security and health hazards. The provision of
including the road width. Bay should be 3.5 m wide
emergency showers, eye-wash stations, etc. needs
• Strong site management is required to ensure ma-
careful consideration.
noeuvring space is kept clear of storage/goods/debris
5. If equipment malfunctions during the treatment
at all times
process, adequate precautions should be taken to
• Headroom clearance should be a minimum of 4.65 m
prevent the discharge of untreated effluent. Such
with careful consideration to ensure all pipework, etc.
precautions should be the provision of emergency
is above that level. Approach gradients to flat areas
collection tasks or the use of approved, licensed,
will reduce the effective height.
effluent-disposal traders.
It is emphasized that the above checklist is not 6. Where accidental discharge of untreated effluent does
exhaustive. Any reductions in the standards identified occur the water authority and/or environmental