Utilities Kingston, owned by the City of Kingston, Ontario, is an international leader in the wastewater treatment fi eld. The $103 million CDN expansion of the Ravensview Wastewater Treatment Plant, located on the shores of the St. Lawrence River, uses state-of-the-art equipment and best practices that serve as a model to municipalities world-wide. By making the plant as efficient as possible, Utilities Kingston (UK) and the City of Kingston help protect the Great Lakes St. Lawrence Basin and communities downstream.
“The City of Kingston aims to become the most sustainable city in Canada, and Utilities Kingston has contributed to this goal in a major way,” says Jim Keech, Utilities Kingston CEO. In 2009 UK completed an upgrade of the existing 50-year-old water pollution control plant from primary treatment to secondary biological treatment with one of North America’s largest Biostyr™ Biological Aerated Filter (BAF) installations. It increased average daily capacity by 30%, from 72,800 cubic meters per day to 95,000 cubic meters per day. Implementing a plant-wide integrated control and power system from Rockwell Automation® helped streamline and standardize plant-wide control, and contributed to UK completing the project under budget and six months ahead of schedule.
Utilities Kingston’s goals for the Ravensview plant were to increase effluent capacity; to improve effluent, air and water quality; to reduce noise; and to provide superior bio-solids handling, energy savings and efficiency.
“As the lead electrical engineer for the project, one of my major concerns is that we meet all the ministry requirements for environmental reporting and compliance,” says Louis Fournier, Assistant Chief Electrical Engineer at J.L. Richards, the engineering company working with Utilities Kingston. To meet these goals, UK wanted to achieve better process and motor control, monitoring, diagnostic and remote access capabilities, improve safety and reduce maintenance. An integrated system upgrades monitoring and reporting, to help meet today’s stringent water industry regulatory compliance. The existing plant was a patchwork of various suppliers’ equipment, based on open specifications and low-cost bids. From past experience, UK found that control platforms with multiple disciplines were difficult to integrate, scale and coordinate.
“If we had multiple MRO [maintenance, repair and operations] systems, we would then have to rely on contractors, who would then have to rely on third-party suppliers – and that adds significant costs to us,” says Allen Lucas, Utilities Engineer and Project Manager for the Ravensview upgrades. The variation from supplier to supplier also made it difficult to assemble tender documents for the contractor bids. UK wanted to find a better way to choose suppliers, manage the risk associated with startup and commissioning cycles, and improve maintenance and troubleshooting procedures.
Utilities Kingston partnered with J.L. Richards (JLR), an engineering, architect and planning company, to design the control system. JLR helped UK to fi nd the right suppliers to partner with for pre-approved equipment to meet specified criteria and deliver the best long-term value. “We put out a pre-selection package for motor control centers and controllers and went out to various suppliers looking for not just equipment but a solution that included partnering with suppliers and integrating the technology from a top to bottom approach,” says Lucas.
A streamlined design and bidding process presents a clear understanding of the features that are most important and leads to competitive pricing. Starting with a pre-selection procurement system known as Quality Based Selection (QBS) was crucial to choosing an integrated control system. “Using the Quality Based Selection model, we tried to focus on the long-term lifecycle costs and overall sustainability, not just the up-front capital costs,” says CEO Keech.
In the municipal market pre-selection of process equipment allows the owner and design team to find a way to competitively select a supplier and then tailor the design to the specific process. A defined specification and a weighted system based on operations, performance, maintenance, safety, and financial aspects, is the key to QBS, but it also takes into account other benefits. “Above and beyond the obvious review of the proposed components,” says Lucas, “a significant portion of the evaluation was based on supplier’s references, experience, proposal clarity, impressions during the full-day demonstration and interview, and their field services and factory acceptance plan,” UK and JLR chose a Rockwell Automation PlantPAx™ Process Automation System solution which included programmable automation controllers (PACs), intelligent motor control centers (MCCs) and variable frequency drives, as well as field services including Protection Plus Startup Services, Factory Acceptance Testing and TechConnectSM phone and online support.
“We pre-selected the MCCs and PACs together because they are the nerve center of the project and we wanted to take MCCs and starters out of the tender document where they are often treated as commodities similar to nuts and bolts,” says Fournier. “Our experience has shown that the integration of the components can often delay a project or in many cases leave a very unhappy client.” To integrate all of Ravensview’s process operations, controls and motor controls into one system, the PlantPAx™ Process Automation System solution uses core Integrated Architecture™ technologies through EtherNet/IP™ and DeviceNet™ wireless communication networks. Ethernet provides computer networking, which replaces conduits and wires for each I/O to help reduce wiring and installation costs, increase reliability and enable point-to-point management and troubleshooting. The Allen-Bradley® ControlLogix® and CompactLogix™ PACs installed across the plant give operators plant-wide, real-time visibility into monitoring, data collection and automated reporting to help operators manage systems, make faster decisions and optimize productivity.
The Ravensview primary effluent pumps, centrifuges, sludge pumps, chain and fl ight sludge collectors, blowers, compactors and HVAC equipment are now controlled using Allen-Bradley motor control centers and variable frequency drives (VFDs) from Rockwell Automation. Allen-Bradley CENTERLINE® 2100 MCCs with IntelliCENTER® technology package Allen-Bradley soft starters to control process applications. IntelliCENTER software provides site operators remote access, real-time diagnostics such as incoming power, pump performance and efficiency and electronic MCC documentation. Access to this type of information helps Utilities Kingston minimize MCC downtime and improve equipment performance.
The Allen-Bradley SMC™ Flex solid-state motor control soft starter installed on the blowers provides intelligence, advanced protection, unmatched performance, diagnostics, and communication. It integrates a bypass to minimize heat generation during run time, which automatically closes when the motor reaches its nominal speed, resulting in a cooler running component and compact enclosure. Also integrated into the plant’s system are the Allen-Bradley PowerFlex® 70 and 700 AC drives that provide improved process control. These PowerFlex drives provide additional process information from the drive level and automatically disperse it to any part of the plant through the architecture.
To measure and provide power-quality reports, UK installed an Allen-Bradley Powermonitor™ 3000 on each MCC, each service entrance and each generator. It performs real-time power monitoring, data and event logs, harmonics analysis, sag and surge detection and load factor calculation. The compact power quality and sub-metering monitor helps UK leverage the DeviceNet networks without the need for cumbersome serial interface bridges. “The power monitors were helpful for the commissioning of the emergency power systems and to provide the operators with feedback on electrical distribution in various areas of the plant,” says Fournier.
UK also installed condition monitoring with online continuous protection. The Allen-Bradley XM® series of intelligent I/O modules processes in real-time the critical parameters used to assess the current health and predict future health of the process machinery. Maintenance personnel can use this to develop optimized maintenance schedules based upon the actual or predicted condition of the assets. Predictive maintenance is a well-proven strategy that can significantly reduce maintenance costs and downtime while improving MRO spares management.
Rockwell Automation also provided a number of services including Factory Acceptance Testing (FAT) and commissioning. The FAT was done at the Cambridge, Ontario Rockwell Automation facility where they built a mock-up of the entire network, including the PACs and Ethernet switches from the project and a sample of each actuator that was to operate on DeviceNet. The system integrator was also at the Rockwell Automation factory where he had direct access to the company’s technical specialists who helped configure the communication devices to meet the tender document requirements.
The four-year proposed Ravensview construction project was completed six months ahead of schedule and $12 million under budget, at approximately $103 million. “Partnering was key to our success on this project,” says Lucas. “Rockwell Automation was one of our best partners in delivering quality on time, and providing all the support we needed to get the job done.”
As a partner, Rockwell Automation provided UK and JLR with technical support from design to commissioning. “In the end what made the difference was Rockwell Automation’s ability to integrate their components from the power monitors and the vibration analysis and to the starters and drives,” says JLR’s Fournier. “The ability to access DeviceNet components remotely via Ethernet/IP on a LAN or a WAN provides significant time savings for maintenance resources that take care of multiple sites.”
According to Fournier, project milestones missed due to unexpected technology integration and start-up issues can cause delays that are calculated at approximately $80,000 per day. The system integrator who assisted in startup and commissioning of the complex network was trained on the PlantPAx Process Automation System. Using one plant-wide control system simplifies training, saves time and facilitates troubleshooting.
“The week that the integrator spent at Rockwell Automation would have easily taken four weeks on site,” says Fournier. “Trying to sort out communication issues on site typically slows down the process.” UK, JLR and the system integrator attended the Factory Acceptance Testing (FAT), which took less than two days. They reviewed the EtherNet/IP network redundancy and the communication of all the PACs and DeviceNet networks, including the operations of the valve actuators. The contractor and system integrator were able to focus on the installation and commissioning of the process rather than the communication of the networks.
“The FAT was a contributing factor to this early completion,” says Lucas. “It is much easier to troubleshoot at a bench than in a multitude of different buildings.” Intelligent motor control also helped reduce installation and commissioning time. In addition to the obvious reduced time required for the contractor to install, terminate, label and verify the various I/O points required in a conventional starter, the system integrator was able to verify the operations of an entire MCC in a few hours.
The new process automation system helped Utilities Kingston go above and beyond environmental impact concerns and regulatory compliance. While increasing capacity by 30%, the Ravensview plant decreased environmental impact, improved air and water quality, decreased odor, noise, air pollution and energy consumption, and provided excellent biosolids handling and efficiency. UK achieved all these benefits, and yet only required two additional staff to manage the all the new equipment and operations and maintenance requirements.
“The upgrades have helped us take waste and convert it into three beneficial products: clean water, methane gas for power generation and biosolids for land application,” says Lucas, “and we’re doing it in an environmentally friendly way.” The new primary digester has thermophilic operation capability, running at 55 degrees C instead of the required 37 degrees C, which exceeds current biosolids management requirements in Ontario, Canada. The increased methane gas produced in the digestion process is used as fuel for a cogeneration unit, which produces heat and electricity for use on-site. The plant operates at about 1200 kW with the cogeneration providing approximately 350 kW of that demand.
“We use Allen-Bradley controllers on each portion of the plant which logs its own data for environmental reporting,” says Fournier. “Should communication go down, the PAC will control the plant in a fall-back position using pre-determined flows and store the data locally. When communication is re-established, the controller will upload the data into the system and continue to trend and log, so we don’t lose any information and ensure the reports don’t have any holes in them.”
The PowerFlex variable frequency drives provide improved pump and process control, leading to improved effluent quality. The upgrade has resulted in reducing the five-day Carbonaceous Biological Oxygen Demand (CBOD5) and Suspended Solids from average monthly approaching 25 mg/L to average monthly below 5mg/L. The change from using only ferric chloride for removal of phosphorus to relying on the biological uptake in the BAF has resulted in a significant reduction of chemical addition. UK reports an overall 75% to 80% reduction in ferric chloride added and estimated 20% reduction in sodium hypochlorite for disinfection. The new PlantPAx Process Automation System from Rockwell Automation has brought Utilities Kingston great short-term and long-term value.
“A centralized control system helps reduce our overall operations and maintenance costs by providing faster response time,” said Lucas. “An operator can come in and get right on the problem and resolve the issue." The Ravensview plant now keeps processes running with minimal human intervention by working effi ciently together and reacting to inputs from other machines. “We chose Rockwell Automation to help streamline and standardize not only our plant operation and control but system wide as we expand to our other utilities,” said Lucas. Utilities Kingston is applying for a Leadership in Energy and Environmental Design (LEED) designation. LEED has no industrial program, but the Utilities Kingston administration building is aiming for a silver LEED designation and general LEED principles are adopted throughout the project.