the challenges in upgrading plant automation for an existing wastewater treatment plant

March 31st and April 1st, 2009 Mile High Industrial and Automation Conference

The Challenges in Upgrading Plant Automation for an Existing

Wastewater Treatment Plant

By Gary Parker, PE

Burns & McDonnell

March 31st and April 1st, 2009 Mile High Industrial and Automation Conference

Agenda

BackgroundData GatheringControl system documentationInterviewing operator and maintenance

personnelDesign PhaseConstruction PhaseControl system startup

March 31st and April 1st, 2009 Mile High Industrial and Automation Conference

Background

Existing WWTP built mid 1980’sPresent capacity 5 MGD, 15MGD futurePlant control system

Local control panels in each process area Loop controllers, lights, pushbuttons

Remote monitoring of major plant alarmsTelephone dialers to call operatorsExisting SCADA for remote sites

March 31st and April 1st, 2009 Mile High Industrial and Automation Conference

Data Gathering

Site surveyCollect control system documentationReview O&M manualsReview plansInterview operations and maintenance

staff for changes to plant controls

March 31st and April 1st, 2009 Mile High Industrial and Automation Conference

Existing Documentation

Shop drawings for each control panelNotes from maintenance staffMaintenance electrician with plant history

left for another companyMemory test of operatorsNo P&IDs existedModifications not documented

March 31st and April 1st, 2009 Mile High Industrial and Automation Conference

Existing Plant Controls

Main Graphic Panel CP-01Local control panels for

Grit CP-03 Blower/RAS CP-07 Digester CP-11 Energy CP-12 In Plant pump station CP-14

Rear view of main graphic panel CP-01

March 31st and April 1st, 2009 Mile High Industrial and Automation Conference

New Plant Control System

Redundant operator workstations New modem and software for alarm dialing Ethernet TCP/IP control system network New PLC panels replacing old CPs for

Operations PLC-01 Grit PLC-03 Blower/RAS PLC-07 Digester PLC-11 Energy PLC-12

March 31st and April 1st, 2009 Mile High Industrial and Automation Conference

New Control System (cont.)

New PLC control panels for: In Plant pump station PLC-14 Dewatering System PLC-08 UV System PLC-09 Iron Salts PLC-16

New RIO panels for: Maintenance/Collections RIO-01 Chlorine Unit RIO-10

March 31st and April 1st, 2009 Mile High Industrial and Automation Conference

Construction Challenges

Constructing pathways for new control system network

Replacing old control panels Tight space to remove and replace Keep old system operational Startup of new control system one point or one

system at a time Training operators during and after installation

March 31st and April 1st, 2009 Mile High Industrial and Automation Conference

Construction Coordination

Daily coordination meetingsOperator assigned to contractor dailyTransfer one system at a timeTest each system before moving to the

next systemFunctional test each area upon completionPoint by point test from field device to

operator workstation

March 31st and April 1st, 2009 Mile High Industrial and Automation Conference

Grit Unit Automation

Alarm annunciatorPilots lightsPushbuttonsMethane gas detectionScreening equipment monitoringGrit equipment monitoringPrimary clarifiers monitoring

Blower System AutomationBlower System Automation

• Existing aeration blower system manual• New system fully automated• Blower current• New basin DO analyzers• New temperature & pressure transmitters• New flow meters• Retrofit bearing temperature and vibration

sensors

Original Blower Building Control Panel CP-07

Alarm Annunciator

Hardwired alarms back to CP-01

Single Loop Controllers

Methane Gas Detection

Pilot lights

Pushbuttons

Years of modifications

March 31st and April 1st, 2009 Mile High Industrial and Automation Conference

Blower Automation

Blower control options Fixed pressure mode Time adjusted fixed mode DO control mode

Blower auto start sequenceBlower failure protectionBlower surge protection

March 31st and April 1st, 2009 Mile High Industrial and Automation Conference

Digester Automation

Tight area to replace control panelAlarm annunciatorMethane gas detectionPilot lightsSingle loop controllerProcess indicators

March 31st and April 1st, 2009 Mile High Industrial and Automation Conference

Energy Unit Automation

Temperature single loop controllersManual pump control through switchesBoiler monitoringDigester gas for boilersRemote alarms to CP-01

March 31st and April 1st, 2009 Mile High Industrial and Automation Conference

In Plant Pump Station Automation

Pump controlWetwell level monitoring through bubblerGrinder monitoringSump pump monitoringRemote alarms to CP-01

March 31st and April 1st, 2009 Mile High Industrial and Automation Conference

New UV System

Retrofit UV system in existing effluent chlorine contact basin

Enclose outdoor basinInterface packaged controls into plant

control networkDemolish gaseous chlorine systemNew sodium hypochlorite system

March 31st and April 1st, 2009 Mile High Industrial and Automation Conference

New Dewatering Building

New centrifuge equipmentIntegrate packaged controls into plant

control systemOwner prepurchased centrifuge equipmentSoilds pump control over control system

network in Digester buildingSolids loadout conveyor system

March 31st and April 1st, 2009 Mile High Industrial and Automation Conference

Thank You

Questions?

Gary Parker, PE

Burns & McDonnell

gparker@burnsmcd.com

303-474-2241