Jones D.S.J., Pujado P.R. Handbook of Petroleum Processing

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ECONOMICS 815

The ﬁling index

The project secretary organizes the project ﬁling system. The ﬁles generated on the

project often become legal documents which may be used for such purposes as ‘job

close out’negotiations, any possible litigation, or inquiries at later dates into industrial

accidents and the like. Maintaining the ﬁling therefore is an important function on the

project, and to accomplish this effectively a ﬁling index is initiated and developed.

This is given in the manual to enable members of the project team to utilize the ﬁles

effectively when required.

Individual engineering, procurement, and design interface procedures

During the life of a project there will a considerable amount of data and information

generated and distributed to the various disciplines in the project team. To ensure the

correct movement of these data etc each discipline develops it’s interface procedures.

For example in the case of a process engineer who has now completed the data sheet for

a pump he needs to ensure that this document is sent to the correct discipline for further

work and ultimately purchasing. In this particular project the mechanical engineer is

designated to be the interface between process and the purchasing department. Then

this section of the procedure manual will detail such interface with instructions of

how the transmittal of the data sheet is to be done.

Drawing index

This is initiated and maintained by the design coordinator. In developing the index as

a list of all the drawings he also demonstrates what the items in the drawing reference

numbers signify. This is updated as the project proceeds.

The remaining items of the manual are self explanatory. These are usually added only

in later editions of the manual. For example just before or immediately after ﬁeld

‘move in’etc.

Monitoring the engineering, procurement, and design phase

With the project now underway the work continues in the home ofﬁce of the contractor

to detail the engineering of the plants, to purchase the equipment and materials to be

installed, and to arrange the ‘lay out’the facility on the site provided by the client.

Each of the various disciplines proceed with their function to meet the progress

milestones deﬁned by the ‘master schedule’. Some of these milestones are ﬁnalized

by conferences of all the contractor’s participants and the client’s project team. The

ﬁrst of these, and perhaps the most important is the mechanical ﬂow sheet conference.

The mechanical ﬂow sheet conference and approval

One of the major objectives of the process engineering’s early activities is to provide

sufﬁcient data to enable other disciplines to commence effective work as early as

possible. A major milestone in achieving this objective is to conference the MFD

816 CHAPTER 17

(mechanical ﬂow diagram) and have it approved by the client. This approval allows

a considerable amount of design work (which is the major man hour user on most

projects) to commence. The development of the equipment data sheets has already

allowed the mechanical engineering and the procurement functions to commence

work but it is the release of the approved mechanical ﬂow diagram that really puts the

activities of the project into top gear.

Participation of the client company in the ﬂow sheet conference depends on the type

of contract and the relative location of the client’s ofﬁces to that of the contractor.

In the case of a cost plus contract however participation by the client is mandatory.

Whether there is client participation or not the ﬂow sheet conference follows some

basic guidelines, and these are described in the following paragraphs:

Preparing for the conference. The contractor’s lead process engineer is responsible

for organizing and conducting the ﬂow sheet conference. The ﬂow sheet that will

be used in the conference will be ‘clean’and free from any pencil or other marks

on the diagram itself. It will be given the revision number ‘0’, and clearly marked.

‘FLOW SHEET CONFERENCE MASTER’.

The diagram will be complete with all lines sized and speciﬁed. Instrumentation will

be correctly shown with control valves sized, relief valves will also be shown but not

necessarily sized at this time. All equipment will be properly titled and labeled in

accordance with the agreed format for ﬂow sheet production.

Accompanying the ‘FLOW SHEET CONFERENCE MASTER’will be the current

revision of the process ﬂow diagram. This will also be ‘clean’with no pencil marks

other than the label “Flow sheet Conference Copy”. The lead process engineer will

also ensure that copies of all the equipment data sheets pertaining to the equipment

shown on the ﬂow sheet are available at the conference. The current equipment list

will also be made available at the conference. Finally, the lead process engineer or the

process engineer he has assigned to the particular process that is to be conferenced

should have available a copy of the process calculations developed. This often helps

to resolve minor issues that may arise.

Attendees. After notice of the conference has been issued by the lead engineer, the

project manager or his assignee will designate the location where the conference is to

be held. He will also issue directives to attendees giving the date, time, and location

of the conference. In cases of major conferences where client representatives are

present professional secretaries may be employed to take notes at the meeting.

Otherwise project engineers will be assigned this task. The notes taken at this

meeting are most important to the ﬁnal approval mechanism. The attendees are

usually:

➢ Client’s representatives (if applicable)

➢ Project manager (usually part time)

➢ Lead process engineer (convener)

ECONOMICS 817

➢ Responsible process engineer(s)

➢ Engineering manager

➢ Area project engineer(s)

➢ Lead discipline engineers (except civil & structural—called for as required)

➢ Design coordinator

➢ Design section heads (piping, instruments, electrical)

➢ Others as required, such as environmental engineer, cost & schedule control

engineers etc.

Conducting the conference. The process engineer conducting the conference com-

mences with a brief outline of the process and its objective. He proceeds to describe

the process using the process ﬂow sheet to illustrate the process ﬂow and the equip-

ment. He then commences with the description of the mechanical ﬂow diagram

which is attached to a wall or suitable frame from which it can be easily read by the

attendees. Now most companies have a color code depicting ‘additions to’,‘dele-

tions from’, etc. Colored pencils are used therefore to cover all such points made

during the conference by marking up the ﬂow sheet as the conference proceeds.

Assume the color coding in this case is as follows:

➢ Yellow—Shows all items that have been conferenced

➢ Red—All changes and additions

➢ Blue—All deletions

➢ Green—Numbers in green refer to note items taken during the conference

The process engineer conducting the conference starts at a suitable point on the left of

the ﬂow sheet. He selects a major line, checks and ‘yellows out’the source label, and

traces the line using the yellow pencil to the ﬁrst equipment item. In tracing the line

he highlights the line number, size, and speciﬁcation shown on the line. The design

coordinator or piping designer checks this against his line list. It must match exactly

or it is marked as requiring further review. All valves and instrumentation along the

line are similarly checked against piping lists or the instrument register.

The equipment item into which the line is connected is checked for correct labeling and

data. These shown on the ﬂow sheet are compared with equipment list, data sheets, and

the process ﬂow diagram for an exact match. The process engineer continues with a

second line in a similar manner. He may elect to go back to the left side of the ﬂow sheet

to select this line or take a line leaving the equipment item. However, the same exercise

is carried out for all lines and equipment until the ﬂow diagram is completely yellowed

out with the discussed notes marked, and with all deletion and changes shown.

This ﬂow sheet conference is a necessary activity but is nevertheless a high consumer

of man hours. The process engineer should therefore use his experience and knowl-

edge to minimize the time taken in this activity. For example: where there is some

considerable contention or where there is an area of concern to the client highlighted

in the conference, the process engineer should attempt to defer a solution until after

the conference. Appropriate note should be made however of the problem and the

818 CHAPTER 17

item clearly marked with a “HOLD”sign. Clients will normally approve ﬂow sheets

with some “HOLDS”providing there are not too many. In further development of the

ﬂow diagram, priority is given to resolving the issue(s) and removal of the “HOLD”.

Immediately after the conference the lead process engineer and the project manager

formally solicits the client’s approval and the release of the project to detail design

work. The approved ﬂow sheet is marked as Rev 1. “Approved for Construction”.

Approval of equipment selection

On a cost plus contract the client’s project manager must approve the selection of

all pieces of equipment that will be purchased and installed. Next to the approval of

the mechanical ﬂow sheet the commitment to purchase equipment is certainly the

next most important. Certiﬁed equipment vendor data are essential for updating the

budget and schedule. It is also important in obtaining correct outline drawings for

certain items to initiate piping lay out and also plot plan development. This certiﬁed

and guaranteed data will only be made available to the project after the issue of the

purchase order.

In addition to releasing the project to essential design work in piping, civil (founda-

tions), and electrical engineering, it also enables the contractor’s process engineers to

build an accurate utility balance. This in turn initiates the engineering of the utility

facilities if this is part of the project.

The contractor’s process engineers initiate this function by developing data sheets that

deﬁne each equipment item. The data in these sheets deﬁne the equipment size and per-

formance required to meet the facilities heat and material balances. On completion of

theses data sheets the contractor’s procurement department complete the commercial

conditions associated with the purchase, and send these documents to a small number

of vendors for each type of equipment soliciting their quotes for supplying the items.

The receipt of the quotations initiates the selection process. Usually the contractor’s

procurement department develops a bid summary list of the quotes from each vendor

for a speciﬁc equipment item. The enter all the associated price and delivery, and to-

gether with the actual quotations, this bid summary is then sent to the process and other

engineering disciplines who analyze the technical content of the quotes giving their

comments on the bid summary. The summary is then reviewed by the cost/scheduling

engineers who compare the offers against the control budget and the master schedule.

They add their comments and route the summary to the contractor’s project manager

for recommended selection. Finally, the client’s project manger receives the package

and the recommended selection. He usually solicits input from his project team before

approving the selection.

If the approval mechanism meets with some problems the client’s project team through

the project manager may request a conference of members of the contractor’s team

ECONOMICS 819

to resolve the problem. This is sometimes requested anyway. After all the equipment

cost is a signiﬁcant portion of the total budget, and more than that an incorrect or

poor selection could well adversely affect the detail design work depending on it, and

even, much later, the construction effort (late deliveries to the ﬁeld etc.).

Purchase orders

With the selection of the equipment vendors, the contractor’s procurement develops

the purchase orders for the client’s approval (for cost plus or omnibus fee contracts).

Prior to this activity usually the successful vendor is invited to the contractor’s ofﬁces

for a pre-award meeting to discuss his offer in detail. The contractor’s purchasing

department prepares the purchase order for the approval signature of the contractor’s

project manager, and, when appropriate the client’s project manager.

Plot plan development and approval

Shortly after the commitment of the major equipment purchase orders, certiﬁed vendor

data in the form of outline drawings, completed data sheets, and the like will begin to

be received by the contractor. These data are received by the purchasing department

whose duty is then to route the data to all the engineering and design departments

for checking and data acquisition. The receipt of equipment dimensioned outline

drawings enable the design department to initiate the plot layout, showing the exact

location of the items relative to one another. This is a combined operation involving

most of the engineering and design disciplines. The key members of this group will be

the process engineer and the lead piping designer. Most contractors will conduct this

activity using small scale wooden models of the items on a scaled board representing

the total site. Computerised piping isometrics and 3D visualizations can be of great

help at this stage.

When satisﬁed with a reasonable layout, the contractor’s project manager will arrange

a conference with all interested parties including the client’s project team, to view

the layout. Comments made at this review will be incorporated and the layout will

be the basis the plot plan drawing. This plot plan will then become the basic tool for

routing pipe ways, electrical and underground piping, and the civil foundation and

structural design.

On cost plus and ﬁxed fee contracts the plot plan requires client approval before use

is made of it for further design work.

Routine progress metings and conferences

Although there is a continual interface between the two project managers during this

phase, there need to be formal meetings between the two teams. This is usually on a

set weekly basis where key members of both teams sit down together and solve the

problems that have arisen or are anticipated to occur in the near future. These routine

meetings are minuted and become part of the project record, although they may be

conducted in an informal manner.

820 CHAPTER 17

A more formal meeting takes place once per month. Again the participants are the two

project managers and their key staff members. Very often senior executives of both

companies may attend, particularly if there is a question affecting either company

policy. This monthly meeting is convened primarily to discuss and review progress

and expenditures. Obviously these topics more often than not involve some technical

interface. Minutes of this meeting form the basis of the contractor’s project manager’s

monthly written progress report. The distribution of this report includes the client’s

project manager, and members of his home ofﬁce senior management, and the con-

tractor’s home ofﬁce senior management.

The master construction plan

At some point toward the end of the engineering phase and when all equipment

is deﬁned, and the bulk of material quantities are known, the master plan for the

construction is developed. As in the case of the project master plan this item is

detailed both in terms of time and in terms of cash ﬂow. In all contracts where the

ﬁeld cost is reimbursable, the client’s project team, including a representative of their

ﬁeld specialist, must be involved. In all projects ﬁeld cost (and, of necessity, schedule)

are signiﬁcant items in the overall project cost. Indeed in many parts of the world where

climatic conditions or accessibility to site is a problem ﬁeld cost are the major item

in the overall project cost.

Among the ﬁrst items in the plan that has to be decided is: What method of construction

is to be adopted? Some of these options are:

Subcontracts

Direct hire

Field erected

Remote modularization

There can be a mixture of these options in the overall plan for the construction, but

the decision has to be made in plenty of time for a smooth ﬁeld move in.

Monitoring the construction phase

With the development of an approved construction plan the client’s project team in the

contractor’s home ofﬁce can be substantially reduced. Most of the engineering work

should be close to completion at this stage. There will still be some design work, such

as detail pipe spooling, electrical, and instrument hook-up details, to be completed.

These do not require the monitoring and input from the client’s team however. The

only two major engineering items at this stage that will require some client input and

approval will be:

The operating instruction manual

The mechanical catalogue compilation

Plant guarantees

ECONOMICS 821

These items continue to be developed through most of the construction phase by

a small contractor’s team consisting of one or two process engineers, a mechanical

engineer, and/or a project engineer. These will be discussed later.

The ﬁeld move in

The extent of the ﬁeld ‘move in’will depend on the type of construction decided

on, the location of the site, and the proximity of the labor source to site. The most

extensive effort in this respect is the situation where it is decided to utilize direct labor

and this labor source is a considerable distance from site. In this case the contractor

must set up a camp for the labor and ﬁeld staff complete with canteen, social facilities

and the like. Developing labor contracts also becomes a major activity for both the

contractor and the client in approving these contracts. In this situation there would be

a deﬁnite advantage in totally subcontracting the work. This ﬁeld aspect of the ‘move

in’would become part of the subcontract.

Monitoring the ﬁeld activities

The activities of the client’s project team during the construction phase is reduced to

monitoring the cost and schedule with respect to the master construction plan. The

team itself will probably be reduced to the project manager and possibly a project

engineer with the process engineer on a part time basis. It is also likely that this smaller

project team will remain in the contractor’s ofﬁce rather than move permanently to

site. Usually monthly site meetings are conducted and the project manager among

others would attend these meetings. During such meetings physical review of progress

in the ﬁeld would accompany an in depth written and verbal report on the schedule

and the cost aspect.

Although the project manager would not be present full time on site, there would be

a client presence there continually. Heading this team would be the client’s construc-

tion specialist, with some project engineering assistance. As the construction work

progresses this team would expand to include specialists in all disciplines who will

follow the installation and testing of equipment relating to these various disciplines.

These would include mechanical engineers, electrical, and instrument engineers. The

follow-up for the piping installation would usually be undertaken by piping specialists

(to check such details as piping layout conforming to plan, pipe stress analysis and the

like). Most clients also include the proposed permanent operators and maintenance

staff of the facility in this team.

Final activities of the project team-mechanical completion

The erection of the facilities is considered complete when all the equipment, piping,

cables, buildings (if any) have been installed, and such testing that is necessary (such as

line and vessel pressure testing) has been done. The contractor is also responsible for

completing all insulation, such refractory lining as may be required, and the disposal

of debris from the site. Most vessels may be left open for ﬁnal inspection by the client.

822 CHAPTER 17

When satisﬁed that all activities required to be done by him according to contract

have been completed, the contractor will issue a formal notice to the client that the

facilities are ‘Mechanically Complete’. With the receipt of such a notice the client

usually has a ﬁxed period according to contract to check the plant out and to inform

the contractor of any defects or omissions to the plant. The contractor will remedy

these items notiﬁed by the client and then issue a formal notice handing over the plant

to the client in terms of ‘Transfer of Custody and Control’. On acceptance of this

notice the client takes over the facilities and prepares to commission them.

Developing the operating manual and plant commissioning

The development of the operating manual occurs toward the end of the engineering

and design phase in the contractors home ofﬁce. Although normally compiled by the

contractor’s process engineers the client’s operating staff invariably participate.

Very often too the process engineers who have been most closely associated with par-

ticular process plant(s) on the project may be required to assist in the commissioning

of those plants. This section of Chapter 17 describes the activities associated with

both these functions.

Developing the operating manual

The operating manual is a compilation of instructions and data reﬂecting recom-

mended procedures for:

Prestart-up conditioning of the plant

Plant start-up

Normal operation, and trouble shooting

Emergency action and shut down

Normal shut down

Catalyst regeneration and de-coking (where applicable)

These procedures include equipment manufacturers’recommended handling, condi-

tioning, and operation of their items of equipment and the experience of the process

engineer who designed the plant. To the process engineer the writing of the operating

manual provides him with the ﬁnal ‘In Depth’review of the mechanical ﬂow diagram

of the plant. During the course of writing the manual he will use the MFD continually

to make reference to the operating procedures he proposes. Anomalies or missing

valves and piping become obvious as the process engineer develops the procedure

logic.

A typical operating manual has the following table of contents:

ECONOMICS 823

Introduction and process description

This will include a brief statement as to the contents of the manual and its purpose.

This will be followed by a process description which will include the “Approved for

Construction”revision of the process ﬂow diagram as reference.

Prestart-up conditioning

This item describes the cleaning out of the plant after construction and its reassembly

following the clean out. For example this item will designate those lines and equipment

that will be ﬂushed out by water and those that will be blown out by air. It will also

describe the equipment and materials that will be used for this clean out such as piping

spool pieces to replace control valves and nozzles and lines that will be blanked

off during this activity. Finally, this item will draw attention to the manufacturer’s

procedures for the various equipment clean out and conditioning. Copies of the actual

manufacturer’s documents relating to this activity should be included in the appendices

of the manual. It is important in order to maintain the warranties that accompany most

equipment that the manufacturer’s instructions be carefully adhered to.

Plant start-up

This section of the manual presupposes that the plant has been properly cleaned, all

utilities to the plant have been commissioned, all equipment is ready for operation, all

drains are free, and ﬁre ﬁghting equipment and procedures are in place. The process

engineer then begins his detailed description of the activities to be carried out in

their proper sequence to bring the plant on line and producing the products intended.

To accomplish this he refers to the MFD. Using this document he describes each

action in the start-up sequence by referring to line numbers, control valve numbers,

equipment item numbers and titles as they appear on the diagram. Normally all these

actions start with introducing the cold feed. For example in the case of the Thermal

Cracker project, cold feed from storage would be used for start-up. Sufﬁcient lines and

valves would be provided for this purpose and the manual text would be somewhat as

follows:

“Open block valves at tank TK 101 and at the plant battery limits on line 1234 CS



ST. Open the suction valves on pump P 106 A and start the pump (Note: Only

the term “Start the pump”need be made as instructions on how to start the pump

are included in the manufacturer’s documents found in the appendices.). Set the ﬂow

control valves 106 FRCV 1 A, B, and C to full open. Set back pressure controller

300 PRCV 1 at the outlet of heater H 301 to 250 psig. Commission the level control

indicator 301 LCI 1 and when the desired level in the bottom of the fractionator is

reached (NLL) open the suction valves to bottoms pump P304 A on line 1235 10



ST. Control discharge ﬂow from pump P304 by activating control valve 301 LCIV 1

on line 1236 8



Cr ST, etc”.

824 CHAPTER 17

Normal Operation

This section carries on from the end of ‘start up’with the unit lined out and in stable

operation. It then describes a series of procedures during normal operation to ﬁne tune

certain parameters, and to maintain the plant on set conditions when minor changes

in feed composition, temperature changes, etc. occur. It must be noted here that in

modern control systems associated with plant operation these type of adjustments are

made automatically with very little need for operator intervention.

The other adjustments that may still require operator action are those associated with

changing the product grade or speciﬁcation. This section therefore still includes a

selected list of operating changes that may be required to be made under normal

operating conditions and the procedures used to make these changes.

Normal shutdown procedures

Normal shutdown procedures are usually divided into two forms, which are:

Short duration shutdown

Shutdown for an extended period

This ﬁrst type of shutdown is that associated with a minor mechanical problem, or tem-

porary loss of feed, or a minor instrumentation problem and the like. In these cases the

feed to the plant is diverted but some or all of the product streams are rerouted back to

take the place of the normal feed. The feed heater, if it is a ﬁred heater, may continue

to be ﬁred on a lower level of operation but sufﬁcient to enable a quick resumption

to normal operation when the fault causing the shutdown has been rectiﬁed. The unit

under these conditions is said to be “Boxed In”.

The second type of normal shut is the more common and occurs when a major fault

has occurred requiring equipment to be taken out of service for repair. This type of

shutdown is also placed on a predeﬁned schedule for routine maintenance. Such a

shutdown requires the unit feed to be withdrawn and the unit itself allowed to cool

down to ambient temperature, de-pressured, cleaned out usually by steam, and drained

free of any hazardous material.

This section of the manual describes both these procedures in the same detail as

described earlier for ‘Normal Start up’. Again the MFD is used as a reference in these

detail procedures.

Emergency procedures

This section is the most important in the manual, and requires careful development

and presentation. Its importance is reﬂected in the fact that very often the preparation

of this section becomes a combined effort of both the client process engineers and the

contractor’s process engineer. Its obvious importance to the safety of all personnel