Case Study 122: LNG Industry Sector: Burner Management • Vaporizer Control System
Process or Machine Automated:
- Submerged Combustion Vaporizer Control Systems
New Technology Applied:
- GE Fanuc 90-30 series PLC
- GE QuickPanel HMI
- Wonderware InTouch SCADA
Project Description:
Staneco Corporation designed controls for multiple liquefied natural gas vaporizers for use in a re-gasification process at a peak shaving facility. Each vaporizer contained a large burner that heated a water bath for the evaporation process. Two PLC systems were utilized for control of each vaporizer; one system for burner management as required per the NFPA and one system for other process controls. All units had automatic ignition and bath temperature control. In addition to the gas control required to operate under normal conditions, interlocks were added to safely handle alarm conditions. Each control system provided feedback to the plant DCS.
Project Outcome:
The addition of these peak shaving units enabled the plant to meet the critical requirements of peak consumption periods. Operators praised the ease of use provided by the control system and the ability to make adjustments to ensure optimal performance.
Case Study 108: Ovens / Dryers Industry Sector: Burner Management • Conveyor Dryer
New Technology Applied:
- Allen Bradley CompactLogix
- Allen Bradley PanelView Plus HMI
Project Description:
Staneco Corporation designed a PLC panel with burner and motor controls for an industrial dryer. The drying process consisted of several stages which were heated by natural gas burners. Each stage had exhaust and combustion blowers which were started automatically by the PLC. The burner ignition was controlled by Honeywell flame relays. The material was carried through the dryer by a conveyor with VFD speed control. The temperature of the dryer stages was controlled by PID control loops in the PLC.
Project Outcome:
The ability to monitor many variables and store product recipes allowed for greater quality control and increased throughput.
Case Study 102: Stack Emission Control Industry Sector: Burner Management • Regenerative Thermal Oxidizers
New Technology Applied:
- Allen Bradley CompactLogix
- Allen Bradley PanelView Plus HMI
Project Description:
Staneco designed controls for two thermal oxidizers used at a corn-to-ethanol plant to remove organic chemicals from discharged air. The oxidizers consisted of multiple gas burners which heated combustion chambers containing ceramic pellets. When the process gas is passed through the pellets, the organic chemicals are oxidized, neutralizing them. In order to prevent overheating of the ceramic pellets, a series of dampers were switched based on either time or chamber temperature. As the chambers were switched, some gas escaped unprocessed. To remove these gases, a purge operation was included to re-circulate the untreated gasses. The motors were controlled over Devicenet which included two VFDs. Temperatures and operation of the valves are monitored and alarmed. Data was made available to the plant DCS system.
Project Outcome:
System met and exceeded the required emission acceptable limits. The process also helped minimize fuel consumption.
Case Study 121: Ovens / Dryers
Industry Sector: Burner Management • Ceramic Sintering Furnace
New Technology Applied:
- Allen Bradley CompactLogix
- Rockwell RSView32 SCADA System
Project Description:
Staneco Corporation designed a sintering oven to produce special purpose ceramics. The process was temperature and time dependent. There were numerous recipes for the different ceramic products produced. The temperature of the furnace was ramped up over a predetermined time to a selected temperature. At various temperatures different gasses were introduced into the process. The flow rate had to be controlled. When the maximum temperature was reached, it was held for a selected time. The temperature was then ramped down once again controlling the gas flows. Since one of the gasses was hydrogen, special interlocking and monitoring had to be used to prevent dangerous situations. The gas flows and temperature over time were logged and put into an Excel file for record keeping and examination. The cycle typically lasted from 12 to 16 hours.
Project Outcome:
Client praised the flexibility of the new system and its enhanced data collection abilities resulting in improved quality control.