Air-Clear’s ThermGen™ Regenerative Thermal Oxidizers (RTO)Thermal Oxidizers (RTO)
Thermal Oxidizers - Thermal Oxidizers efficiently reacts Hydrocarbons (HCs) and Volatile Organic Compounds (VOCs) with oxygen in the air to form naturally occurring carbon dioxide and water vapor (HC+O2+ HEAT --> H20 + CO2). This reaction occurs when the air is heated to a sufficiently high temperature, typically 1400-1600ºF (760-870ºC). are the most energy efficient, cost effective solutions for the reduction of VOCs and odorous air emissions…here’s why:

Thermal Oxidizers - Thermal Oxidizers efficiently reacts Hydrocarbons (HCs) and Volatile Organic Compounds (VOCs) with oxygen in the air to form naturally occurring carbon dioxide and water vapor (HC+O2+ HEAT --> H20 + CO2). This reaction occurs when the air is heated to a sufficiently high temperature, typically 1400-1600ºF (760-870ºC).

• Ceramic energy recovery beds Ceramic Energy Recovery Beds
  RTOs - To achieve high levels of heat recovery, RTO's use multiple regenerator chambers (beds) containing ceramic heat transfer media, with each bed used to alternately store and release heat created by the oxidation process. Air-Clear designs and builds units with any number of regenerator chambers (from a minimum of two), based on specific process and performance requirements. capture and reuse up to 95% of the systems energy. The result is low fuels cost.
• Heat released from the oxidation of the VOCs is also captured in the recovery beds which further helps reduce supplement fuel use. In fact, with a VOC concentration of about 3% of the LFL LFL
  Lower and Upper Flame limits (AKA LEL and UEL) are the respective minimum or maximum concentration levels of vapor of a flammable or combustible material (expressed as percent by volume in air) at which an explosion will occur in a confined area if an ignition source is present. No explosion can occur in the presence of very low or very high concentrations.
  
  As an example the LFL of Toluene is 1.27% of the mixture or 12,700 PPM. At 3% of the LFL is 381PPM and the process gas will have a heat output of about 88⁰F, enough to self sustain a 95% thermally efficient RTO. the ThermGen™ RTO is self sustaining, that is no supplement heat input is required.
• Requirements for MACTMaximum Achievable Control Technology (MACT), BACTBest Available Control Technology (BACT), LAERLowest Achievable Emission Rate (LAER)  and RACTReasonably Available Control Technology (RACT) making it the preferred oxidation technology for many applications.
• Highly effective at reducing VOCs by means of thermal oxidationOxidation
  (HC+O2+ HEAT --> H20 + CO2 + Exotherm ) , eliminates as much as 99% of the VOCs meeting the EPA requirements for MACT, BACT, LAER and RACT making it the preferred oxidation technology for many applications.
• "In house" fabrication …from controls to reactors…insures our customers that Air-Clear maintains quality and schedule control over their projects
• Seamless interface between our customers process and the ThermGen™ RTO with PLC tailored to the processes operation
• Flexibility when selecting system components such as structured vs. random heat recovery media, burners vs. electric heating elements and carbon steel vs. alloy construction gives our customers the best of both worlds, proven technology custom tailored to their specific project conditions
• "Dirty" process streams are controlled using a variety of pre-filter(s)

  Air Clear has been a leader with regards to pre-filtation of troublesome particulate for oxidizers, primarily RTO's. By applying our Fiberbed mist collection, we have provided several prefilters to our customers…and even to our compition! Preventing particulate from entering the RTO inlet has several major advantages:

  *Protects the blower from buildup of particulate which can unbalance the fan leading to poor performance and a shortened life. In the past the answer was to make the fan an ID fan that is placing it at the outlet of the RTO. However this adds additional horse power to the fan motor and when a hot bypass is needed additional cost for cooling.

  * The prefilter also protects the heat recovery media from plugging which adds to pressure drop (more power needed) and shortened media life which adds to the operating cases. Prefiltration can reduce the need to replace media from as frequently as once a year to five to ten years. The savings from this easily pays for the prefilter.

  *In those cases where the particulate is organic and therefore combustible, such as the asphalt shingle industry, the removal or at least the reduction of this material helps prevent potential catastrophic damage caused by bed fires.

  and media "bake clean"Bake Clean
  The bake clean (AKA bake out) removes organic materials that may build up on the cold side of the media (bottom) beds. Much like the principal of a self cleaning oven, the media is heated until it has been ‘baked clean’. option
• FAT

  FAT
  All Air-Clear Systems are designed, manufactured, assembled and tested prior to shipment to ensure trouble-free installation and start-up:

  Major components, such as burner systems, fans, VFD, flow control valves, instrumentation and control programming for process and safety interlocks, are tested at Air Clear's facilities prior to installation at our customer's site.

  When practical, the equipment is totally assembled for verification of fit of components. Shop assembly and testing allow Air-Clear Engineers to verify performance prior to shipment. Any non-conformity is corrected before installation at the customer's site.

  Benefits to the customer are:

  • Faster, trouble free installation reduces installation costs
  • Less downtime, increased revenue from production
  • Higher on-line reliability from day number one
  • Higher on-line reliability from day number one
  • Our customers are encouraged to witness the shop testing. This is often an excellent opportunity for our customers to receive training on the equipment this allows for the customer's personnel to become comfortable and knowledgeable with the equipment before it is even shipped!
  - Factory Acceptance Test – reduces commissioning and start up time by running a thorough diagnostic system check PRIOR to shipment

Air-Clear has extensive knowledge of various materials of construction and metallurgies to insure long-term system performance and reliability, especially when working on Chlorinated Chlorinated
When chlorinated compounds are oxidized one of the resulting by products is Hydrochloric Acid (HCL).This HCL must be neutralized or scrubbed and requires auxiliary equipment in the form of a quench to lower the temperature and a Caustic scrubber to neutralize the HCL before being released to atmosphere. The HCL also presents a potential metal corrosion problem for the Carbon Steel. To combat this AC often fabricates all or part of the RTO using corrosion resistant materials. Protective coatings are used beneath the insulating modules to offer addition protection to the steel. applications.

Air-Clear quench / scrubbersQuench / Scrubbers
AC’s capability to provide a complete integrated system insures a seamless interface between the RTO, Quench and Scrubber. are used to remove acids such as HCL, HbR H₂SO₄ when formed during the oxidation reaction

Secondary Heat (energy) Recovery (SHR) systems to provide for positive payback from the abatement equipment

• In some cases the waste heat from the hot combustion exhaust (which normally is vented to the stack),are recovered in a secondary heat recovery system resulting in additional energy savings. Contact Air-Clear Engineers to analyze your project for secondary heat recovery feasibility

  Heat Recovery Feasibility
  The following are examples of the how the waste heat can be utilized for process or plant use:

  • Reheated air - return to process or as building heat
  • Waste heat boiler - to produce process steam or hot water
  • Hot oil heater - to produce hot oil for use in the process
• "Flameless"Flameless
  By using special heating elements,supplemental heat is added without the use of a gas fired burner hence no flame and therefore no burner NOx is produced. electric systems use electric heaters that generate little or no NOX emissions
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Hot Bypass Valve (HBV)
• In some cases, a Hot BypassHot Bypass
  The pollutants often referred to as VOC’s (Volatile Organic Compounds); provide a heat release as they are oxidized or combusted. The higher the VOC concentration, the more heat is released, reducing the amount of supplemental fuel required to maintain the oxidization temperature. In combination, the heat recovery and VOC's heat output can often provide sufficient heat to reach the oxidation temperature without any burner heat input. In fact, at times the VOC loading can provide more heat than is needed to maintain the oxidation temperature. This excess heat can cause unstable operation or unscheduled RTO shutdowns and in extreme cases can cause damage to the RTO. To prevent these concerns, a Hot Bypass is used to direct the clean oxidizer exhaust around the primary heat exchanger. This redirection of hot air directly to the stack which creates an unbalanced flow in the heat recovery system (more dirty cold air than clean hot air). The result is a lowering of the preheat temperature and a return to stable operating conditions.
  
  The ThermGen™ Regenerative Thermal Oxidizer (RTO) uses a specialty high temperature (1400°F-1600°F) damper with modulating control. Designed for the constant exposure to high temperatures, these high temperature valves have minimal leakage even after years of use. is used to direct the clean (hot) oxidizer exhaust around the primary heat exchanger to avoid damage to the pre-heater.
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Insulation

A key design feature of the Thermox™ Recuperative Thermal Oxidizer is the use of high-density ceramic modules  Modules

• Unlike some of Air-Clear competitors who use blanket and pin, Air-Clear uses ceramic fiber modules. While these modules are initially more costly, the energy saved and the long life expectancy with virtually no maintenance makes modular insulation the best overall value
• A stainless steel frame supports each module; the frames are individually welded to the inside of the combustion chamber. When the adjacent module is put into place, it generates lateral support by compression.
• Air-Clear modules are made from high purity ceramic fibers. The modules are constructed to prevent spalling or erosion of the fibers which would normally result when the fibers expand in different directions when heated.
• Efficient, durable and low maintenance make the Air-Clear insulating system a key part of the RTO System.
• In corrosive environments where acid gases create the potential for attack on the oxidizer walls, the modular construction studs provide a unique solution.
• With the module in place the wall temperature is approximately 150°F, well below the maximum temperature of corrosive resistant mastics. This allows Air-Clear to coat the interior surfaces prior to insulating the unit, protecting the metals from acid condensates and corrosion.
• Smaller diameters make modular insulation a bit more difficult. In some applications Air-Clear uses high-density ceramic fiber sleeves to insulate the combustion chamber. These sleeves are particularly useful when lining smaller reactors with diameters under 3'.
• Two or more sleeves are interlocked by means of a staggered joint connection. The round fiber sleeves are strong and chemically resistant. They can be brought rapidly up to temperature without concern for cracking or spalling. This proprietary sleeve method of insulating is often used in the Air-Clear Chameleon System. These trailer-mounted units are designed for over the road transportation.
• The principal advantage of this insulating method is that the outside shell temperature can be controlled to temperatures around 140°F (60°C) even with the high chamber temperatures. This cool skin temperature allows for the use of a carbon steel shell. The lower cost of carbon steel allows Air-Clear designer engineers to build the chamber in many formats, depending on the site conditions.
• The lower cost carbon steel also allows the ThermGen™ Regenerative Thermal Oxidizer System to incorporate large retention times which in turn provides for excellent destruction efficiency.
to internally line the combustion chamber. This insulation is suitable for operation at temperatures up to about 2300°F (1260°C), so it has no problem operating at the "cooler" operating temperatures (1500-1800°F/ 815-980°C) of the Thermox™ Recuperative Thermal Oxidizer System.
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Coatings

Another advantage of the fabrication/insulation method used on the ThermGen™ Regenerative Thermal Oxidizer RTO System is that the low exterior shell temperature which allows the use of a variety of Standard Industrial Coatings.Coatings

• A typical ThermGen™ Regenerative Thermal Oxidizer… RTO System is epoxy coated in our shop.
• In addition to our epoxy coatings, Air-Clear has applied numerous custom coatings in a virtual "Rainbow" of colors. The surface preparation is tailored to the coating requirement, and insures that the ThermGen™ Regenerative Thermal Oxidizer …RTO’s appearance will be as durable and long lasting as the rest of its components are.
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Fans
• A backward inclined industrial grade centrifugal fan is used because of their efficiency and ability to perform over a wide operating range.
• Air-Clear Engineers utilize leading Fan Manufacturers assuring optimum fan performance for the appropriate process. Air-Clear Engineers select fans so that they perform at approximately 90% of total capacity. This provides the customer with a quieter fan and extended fan life.
 A backward inclined industrial grade centrifugal fan is the fan of choice for most Thermox™ Recuperative Oxidizer Systems
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Programmable Logic Controller (PLC)

PLC's are available with input and output (I/O) options and electrical configurations that make them ideal for a wide range of applications

Air-Clear Engineers have experience with many PLC Manufacturers. Program Logic Controllers (PLC's) provide the following advantages over relay logic control.
• Fast, specific diagnostics
• Remote monitoring
• Easy data acquisition
• Easy operator use with various levels of access
• Interfaces/integrates easily with process operations
• Cost effect in most applications
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Field Support

Field supportSupport
Air-Clear has full-time field technicians and engineers ready to support all of Air-Clear's equipment. Additionally, Air-Clear often provides in-depth training to local mechanical / electrical contractors who can support Air-Clear's field technicians. Field support can be extended indefinitely by means of maintenance / service contracts. Remote support for our customer's personnel is only a phone call away. Air-Clear Engineers can dial up equipment through modems integrated in our controls to provide real time monitoring and diagnostic services. is provided throughout the world on all of Air-Clear Systems

Complete TurnkeyTurnkey
Air-Clear can provide a range of installation services to suit each customer’s requirements. These can include assembly crews or supervision of customer crews, startup assistance and complete "turnkey" responsibility. Air-Clear strives to offer those services that will minimize the installed cost of our systems. Service

Remote MonitoringRemote Monitoring
Air-Clear offers remote monitoring, enabling us to monitor the status of your systems, diagnose problems, and change operating settings from our offices in Elkton, MD. This allows Air-Clear to quickly determine the status of your systems, without the delay of waiting for a technician to arrive at your site. Services can include daily monitoring and data logging of operating parameters, remote diagnostics and troubleshooting, and adjustment of operating parameters. These services can be provided not only for Air-Clear RTO Systems, but also for a variety of other equipment. Please contact Air-Clear to discuss your particular monitoring needs Services

EngineeringEngineering
Air-Clear offers various engineering services to our customers. These include permit assistance, remote equipment monitoring and process integration. Many Air-Clear customers look to us for help not only in integrating their emission control systems into their process, but also to upgrade their entire process control and monitoring systems. AC's expertise from experience in other industries can often bring a fresh perspective to the table Services

PilotPilot
Air-Clear has RTO pilot systems available for use. These are used to demonstrate the benefits of our technology, and to optimize system design prior to full-scale system fabrication. Most pilot systems are small, skid-mounted units with a complete integrated control system. These pilot units include most of the features of our full-scale systems, and allow the evaluation of optional components Testing

Sales SupportSupport

• Our technical sales team is committed to understanding the unique requirements of our customers on every project.
• Our technical sales team is passionate about seeking out new technologies while constantly improving existing designs.
• Our technical sales staff has a combination of 90+ years of technical expertise and unequaled dedication to customer service that sets Air-Clear apart from the others
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