When you invest in Regenerative Thermal or Catalytic Oxidizer (RTO or RCO) systems that provide the best and most economical solution, you will see the positive effects on your bottom line. NESTEC continues its quest to provide the best and most economical solution for Volatile Organic Compound (VOC) and Hazardous Air Pollutant (HAP) management and odor control applications.
NESTEC’s three hundred and forty-five plus (345+) years of key staff experience with RTO and RCO design, fabrication, and installation on VOC, HAP, and odor control applications. Our experience provides the knowledge and insights into new and innovative features to tailored to specific applications and designed to extract even greater operational efficiencies.
Until now, hydraulic or pneumatic actuators have been the primary component in the operation of RTO/RCO flow control valves.
NESTEC’s NEW PATENT-PENDING ELECTROMECHANICAL ACTUATOR CONTROL system uses linear motion machine designs that are increasingly specifying electromechanical actuators. These systems are cleaner, easier to control, and require less maintenance than hydraulic or pneumatic cylinders.
NESTEC’s new electric actuator offers:
- Safety benefits
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- By enabling operators to ramp up speed, slow it down, follow a consistent motion profile or hold a position, electromechanical actuators give them maximum control over the load for the application
- Valve can be positioned at any interval throughout travel – useful during setup and during inspections, and can be programmed for a variety of fail-safe positions
- Valve can be locked out at any position
- Over-travel (blade deflection) can be adjusted via stroke or pressure (amperage)
- “Soft seat” the valve instead of slamming the blade into the seat
- Electronic position setup of the poppet-style valve (not mechanical)
- Poppet valve control via an ethernet connection (simplifies field wiring and reduces cost)
- Compact housings are easier to seal, thus eliminating contamination risks (fewer moving parts means less wear and tear and lower risk of failure)
- Implementation and operation of performance monitoring is much easier because most of it is accomplished with software rather than external systems
- Electronic actuators can accept commands and, in return, provide safety-related data such as load or temperature
- Operations can be shut down easily in the event of an incident
- Electronic systems can be overridden manually if necessary
- Operation is silent, removing the danger of hearing impairment for those who are constantly exposed to it
- As attention to workplace safety grows among government regulators and the public, it has become an important consideration when designing for a green motion control solution; electromechanical actuators address the safety disadvantages of hydraulic or pneumatic cylinder-based systems
- By enabling operators to ramp up speed, slow it down, follow a consistent motion profile or hold a position, electromechanical actuators give them maximum control over the load for the application
- Fast acting response
- Acceleration and deceleration control (automatically adjustable for each application)
- Valve seat over travel for next to zero leakage control (easily adjustable for each application)
- Internal end of travel position switches
- Programmable variable adjustments for all controls (no mechanical adjustments)
- Positive feedback on actual position (control precision and flexibility)
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- Electric actuation with analog control for precise control of the valve position and minimization of the sealing force to achieve proper sealing of the valve blade to valve seat
(Current pneumatic systems with on/off actuation oversize the cylinders to allow for any misalignment or imperfections in fabrication, causing the mechanism and housing to be overdesigned.)
- Reduced mass required for blade, shaft, and couplings
- Eliminates the need for expensive threaded shaft and coupling
- Tie rod extension mounting ensures alignment
- Anti-rotation coupling further reduces required parts
- Servo-drive data available to Historian for trend analysis
- Critical drive parameters can be programmed and altered from secured HMI screens without connection to PC or laptop
- Poppets can be programmed to half travel, allowing process flow bypass to stack
- Servomotor encoder and servomotor VFD amperage feedback allow for warning and shutdown alarming on extension and retraction actions
- Total cycles can be logged for life expectancy calculations
- Can be backed up by either 480 V 3 PH power or DC voltage direct to buss
- Positive confirmation of valve seating via rise in amperage
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- Poppet-style valves are subjected to thermal expansion
(Generally, the temperature is 100 – 200 0F hotter on the outlet than inlet of an RTO. Bakeouts will have higher temperatures, typically 600-700 0F. This temperature gradient creates expansion between the inlet and outlet valve seat and becomes greater with larger valves. Analog actuation with controls will automatically adjust for any change in valve growth by seating the valve based on pressure, not a fixed distance.)
- Servomotor encoder and servomotor VFD amperage feedback allow for warning and shutdown alarming on extension and retraction actions
- Early indication of failure via changes in amperage over time
- No pneumatic air required
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- One less utility for the customer
- Elimination of all parts and issues associated with the pneumatic system (regulators, pressure switches, valves, hoses, filters, accumulators, piping, check valves, supply issues, moisture, etc.…)
- Operational in cold weather
- Lower maintenance, increased reliability, reduced noise (from venting of cylinder)
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- Programmable
NESTEC’s unique innovative poppet valve assembly design enables RTO DRE (Destruction Removal Efficiency) of 99% + with a fast acting, simple, rugged, reliable, and easily accessible valve assembly, now available with an electromechanical actuator.
- One valve for both inlet and outlet control
- Includes unique designs to prevent slamming into the seat and maintain a tight seal
- Self-cleaning heated seat
- Allows for thermal expansion for the complete operating range of conditions
- Self-aligning shaft and actuator
- Hinged, easy access door
- Locally fabricated replacements components are possible
- Access to NESTEC’s warehouse inventoried components
While often overlooked, there are the many intrinsic safety benefits that come with using electromechanical solutions. Electromechanical actuators eliminate the need for
hydraulic fluid systems and/or pneumatic air systems.
The inherent characteristics of hydraulic oil and/ or pneumatic actuators, can result in any of the following problems:
- Physical trauma: High-temperature, high-pressure systems present potential risk even in routine operation, but as these hydraulic or pneumatic components wear and fail, the risk of danger increases. Proximity to hydraulic lines can potentially result in burns, bruises, cuts, or abrasions from hydraulic lines.
- Exposure risk: The U.S Agency for Toxic Substances and Disease Registry reports that some types of hydraulic fluids can irritate skin or eyes and that ingesting certain types can cause pneumonia, intestinal bleeding, or death in humans. The fluids also require fire retardant capabilities when used with an RTO/RCO.
- Contamination: In addition to being potentially toxic to humans, hydraulic fluids can be harmful to the environment. The U.S. Environmental Protection Agency (EPA), for example, includes hydraulic fluids on its list of oils that require special handling. Slip and fall hazard.
- Cleanup: Indoor spills may also be subject to local regulation or require additional investment in absorbent substances or other cleanup services.
- Combustibility: Petroleum-based hydraulic fluids are less flammable than petroleum middle distillate fuels such as jet fuel, kerosene, or diesel fuel. These can, however, be a fire hazard if sprayed, as might happen when high-pressure leaks convert the fluid to an aerosol state.
- Ambient temperature: Both hydraulic and pneumatic systems have issues due to ambient temperature changes. Pneumatic systems require a dryer system to minimize moisture and prevent potential freezing on system exhaust. Hydraulic systems have viscosity issues that affect the valve timing.
However, NESTEC’s quest to eliminate or minimize the air emission control system’s effect on the plant’s bottom line, has led to the development of an electromechanical actuator that duplicates the pneumatic actuator performance, but also offers additional features and savings.
NESTEC’s new electrical valve actuator:
- eliminates the need for dry pneumatic air and associated cost
- compressor and piping associated cost
- air dryer and associated cost
- eliminates end limit switches (and their mechanical adjustments and associated cost)
- eliminates the thermal expansion problems and expense associated with complicated, machined rotary valve RTOs
- eliminates the excessive wear and binding problems linked to thermal expansion with a rotary valve RTO
NESTEC’s solutions have led to substantial cost reductions in RTO/RCO capital equipment as well as long term operating costs, thus providing the best and most economical solution for the application. The NESTEC approach offers a total air emission control system with alternate options for the capital equipment system and associated operating costs. We provide a matrix of potential solutions that can lead to the best and most economical solution for your specific plant air emission control and energy conservation needs.
If you have an application or existing RTO/RCO for air emission control and/or energy conservation and want a system that will deliver:
- lower energy bills
- alternate solutions to minimize your capital expenditure
- stack testing costs reduced to a single stack
- a smaller carbon footprint
- easily maintainable equipment
- simple, reliable, long lasting components (see: https://www.nestecinc.com/news/innovation/)
- 24/7 service and engineering support
- access to NESTEC’s warehouse of replacement components
Contact NESTEC for a free process analysis and proposal.
Office: 610.323.7670
Jim Nester, CEO.: jnester@nestecinc.com
Rick Reimlinger, Vice President: rick.reimlinger@nestecinc.com
Rodney L Pennington, PE, Sr. Director- Specialized Sales: rpennington@nestecinc.com
Bill Holden, Services Manager: wholden@nestecinc.com
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