Innovative Control and Optimization of Fired Heaters

9-1229

Innovative Control and Optimization of Fired Heaters

9-12299-12299-1229

Mark BrewerRadu Iscovici

AgendaAgenda

� Introductions (Presenter, Rompetrol, Emerson Team)

� Control Objectives & APC Scope� Control Design, Implementation & Commissioning� Business Results� Summary

PresenterPresenter

� Radu Iscovici

� Head, Process Control Department at Rompetrol Refining SA, Romania

� In charge of: � profit increase through advanced regulatory controls

and advanced process control and optimization and advanced process control and optimization techniques

� safe and secure plant operation through safety instrumented systems implementation;

� data collection, transfer and processing into valuable information for management through implementation of IT industrial systems

PresenterPresenter

� Mark Brewer

� Senior Consultant� Emerson Process Management, Strategic Services

Group, UK� Advanced Control and Optimization Specialist

Project ExecutionProject Execution

� Project Team� Emerson

� Emerson Romania� Strategic Services (UK)� AAT (US)

� Rompetrol� Rompetrol DCS Engineer and Control Engineer � Rompetrol DCS Engineer and Control Engineer

embedded as part of the execution team� This strategy ensures greater understanding of the

installed system thus developing on-site champions of the APC technology

� Any DCS configuration work carried out by Rompetrol personnel

Rompetrol – An OverviewRompetrol – An Overview

� A leader in the regional oil industry � Rompetrol is a multinational company with activities

in 13 countries � Strong operational base in the Black Sea and

Mediterranean Sea region � The number and the complex nature of the projects

executed at a global level have turned Rompetrol The number and the complex nature of the projects executed at a global level have turned Rompetrol over time into the best known international brand originating in Romania.

� Co. Size: 9,000 Employees� Industry: Oil & Energy� Website: http://www.rompetrol.com

� Built in the 1980’s by Petromidia, a Romanian national owned company

� Now owned by Rompetrol� Largest Romanian refinery (100,000 bbl/day)� Recently modernized with Emerson’s DeltaV DCS� Continuous drive to improve operational efficiency

Constanta Refinery – A brief history Constanta Refinery – A brief history

� Continuous drive to improve operational efficiency through exploitation of new DCS functionality and smart field instrumentation

Emerson Process ManagementEmerson Process Management

� Strategic Services Group� UK Based (Middlesbrough)� Support for Europe. Middle East &

Africa� Consultancy in advanced control

and optimizationand optimization� Process experts with 10 to 30

years experience (ex operating companies)

� Experienced project managers� Process-specific technical solutions

(oil & gas, refining, chemicals, utilities)

CDU PlantCDU PlantGas

Naphtha

Kerosene

To Vacuum System

Steam

Steam

Fired Heater Vacuum Tower

Atmospheric Tower

Crude Feed

Lt Diesel

Diesel

AGO

LVGO

HVGO

Residue

Steam

Steam

Steam

Steam

Fired Heaters

IntroductionIntroduction

� 2 fired Heaters in parallel� Each fired heater has 2 process passes� Control Objectives

– Good temperature control in outlet– Good total flow control– Optimization (minimise excess air)– Optimization (minimise excess air)

� Disturbances– Feed inlet temperature and flow changes– Fuel quality changes

� Interactions � Constraint Avoidance

Solution: PredictPro® / SmartProcess®

HeaterSolution: PredictPro® / SmartProcess®

Heater� Control total feed to target with allocation for up to 4

passes� Control outlet temperature to the desired target� Adjust inlet air and draft dampers to minimize excess

air� Combustion control including fuel/ air cross limiting� Stabilize heater against changes in fuel gas and feed

temperature� Operate within all heater constraints

PredictProCV (Control Variables)

MV (Manipulated Variables)

LV(Limit Variables)

DV (Disturbance Variables)

::

::

::

:

Potential ProblemPotential Problem

� One heater has no automatic air flow control but we need to minimise the excess air.

� Soultion:– Use process flow rate to change heat demand, which in turn

changes the fuel requirement allowing us to push the excess air ratio to the optimum position.air ratio to the optimum position.

– The second heater (which does have a variable speed drive on its air fan), can then be used to control the total flow to the downstream process.

Control DesignControl Design

dT

T

O2

Air P

F

F

CO2

P T

TO2CO2

F

Control Variables

Constraint VariablesManipulated Variables

Disturbance Variables

Cold Process Feed

Fuel Gas

Air P

F

CV

dT

T

Fuel Gas

Air

P

F

F

P T

F

CV

s

Hot Process Feed

Note: Fixed air Flow (manual adjustment in field)

User InterfaceUser Interface

Business ResultsBusiness Results

� Annual Fuel Saving of $100,000

� Heaters require less manual actions

� Heaters can manage load changes

Baseline Period APC Period

1/7/07 to 30/09/08 12/03/09 to 27/3/09

Average Stack Oxygen 5.13% 4.41%

Average Efficiency (from US DoE table) 79.31% 79.65%

Typical fuel usage 2200 Nm3/h 2190.34 Nm3/h

Typical fuel Saving 9.66 Nm3/h

Fuel Price 0.25 $/Nm3

Saving 2.37 $/h

$21,000/year load changes

automatically� Heaters can now be

used to control Atmospheric column in closed loop mode.

Baseline Period APC Period

1/7/07 to 30/09/08 12/03/09 to 27/3/09

Average Stack Oxygen 5.83% 3.81%

Average Efficiency (from US DoE table) 76.05% 77.39%

Typical fuel usage 2200 Nm3/h 2161.99 Nm3/h

Typical fuel Saving 38.01 Nm3/h

Fuel Price 0.25 $/Nm3

Saving 9.34 $/h

$82,000/year

SummarySummary

� PredictPro to optimize heaters� Oxygen control without air flow

control!Saving $100,000 per year� Saving $100,000 per year

Question TimeQuestion Time

Thank you for your attention!

Questions & FeedbackQuestions & Feedback

� Other, Related Sessions – Inferential Analyses Enhances Benefits of PredictPro Controllers in

Crude Fractionation (9-1231)– Dynamic Simulation of Fractionation Columns in PredictPro (9-1232)– PredictPro Delivers Results at Rompetrol’s Constanta Refinery Crude

Fractionation Unit (9-1228)

Where To Get More InformationWhere To Get More Information

� More Information Available From: Paul Dima

Emerson Process ManagementGara Herastrau 2-4, 5th Floor 020334 Bucharest ROMANIA

Tel +40 21 206 25 00Fax: +40 21 206 25 20paul.dima@emerson.com

Mark Brewer

Emerson Process ManagementEggleston Court, Startforth RoadMiddlesbroughTS2 1PTUK

T 44 1642 773024mark.brewer@emerson.com