Energy Savings and Improved Uniformity with the Airtorch®  – Deep Decarbonization

Increased energy efficiency can lower greenhouse gas (GHG) emissions and other pollutants and decrease water use. Global temperature and CO2 levels are correlated. However, the Earth’s average temperature fluctuates yearly due to natural variability in Earth’s climate systems. This means a particular year can be cooler than a previous year, even if CO2 concentrations have risen. Electrification (deep decarbonization) in the industrial sector and improved efficiencies (decarbonization) can quickly reduce CO2 and methane emissions.

1 KWh (3,600,000 Joules) of electric energy can save at least ~0.2 Kg of CO2 from being emitted on average (please see the emissions table for specific fuels on the right) when choosing electric heating over fossil fuel heating.

Economic: Electric methods are generally more efficient in energy usage than combustion heating. Improving energy efficiency can lower utility bills, create jobs, help stabilize electricity price volatility, and improve the climate.

Energy Cost:  When one includes the social cost of CO2 production, the price of one KWh of electric or combustion energy starts converging. The CO2 emissions per million kilojoules of energy used range from 50.4 Kg for natural gas to 68.8 Kg for jet fuels. The social cost of making CO2 is $50-$105/ton. Typically a 30% improved efficiency is noted in electric devices over combustion (fossil-fuel) heaters. If the efficiency of Airtorch devices is even 25% better than combustion heat exchangers, then the operational cost of the electric Airtorch could be lower than the combustion heat exchanger devices. For example, a 14.2 MW combustion gas heater could be replaced with a 12MW electric Airtorch. A savings of $48,000 per day (assuming 1 KWh ~10 US cents). Did you know that converting from a 16MW combustion heater to an Electric Airtorch can save over 30% energy and several millions of dollars in climate costs?

There are additional benefits with the MHI Airtorch. The pressure drops for electric Airtorch devices are lower than traditional heat exchanger devices.   For a 2000 SCFM flow, saving ~5 psi in pressure drop is equivalent to about 30 KW in power savings. This is almost a savings of $25,000 per year, assuming a price per kWh of 10US cents.   

MHI Airtorch® models are designed with thermal energy loss reduction and pressure energy loss reduction features. MHI Airtorch® models offer a high-temperature input, even to 500°C, which is particularly useful for duct heaters used in ovens to replace natural gas heating.

For the best energy saving, compare the following:

  • The efficiency of thermal transfer. What is the actual energy conversion efficiency to theoretical efficiency? Depending on the model, the MHI Airtorch® systems offer more than 95% efficiency.
  • Pressure drop. Some large MHI models allow a pressure drop at 1000C of as low as 0.1 psi (3wc).
  • Control systems. Good controls offer an excellent turn-down ratio with intelligent cascade electronics. MHI uses the best SCRs and electronics that are industry standards.
  • Materials and Design. What is the best temperature rating of the Airtorch?®. Depending on the model, MHI Airtorch® systems offer 1200°C exit temperatures. A higher temperature-rated Airtorch® will perform better and last longer even at a lower temperature.
  • Productivity vs. Temperature (in pdf format)Processing Productivity vs Temperature
  • Improvement of over 30% in energy efficiency compared to …..(click here for case studies)
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  • Energy-saving Tips

    1. If lesser energy can be used for the same objective, it will substantially reduce CO2 emissions. Modern light generators (bulbs) produce the same visible light intensity with much less energy. So does an Airtorch (process air and gas generator)  or a modern decarbonized steam generator.
    2. Improved practices. There is no need to pressurize compressors and bleed them every day. Pressurization leads to substantial energy demand. If using high-volume airflows, ensure that the pressure drop is the least.
    3. An electric Airtorch device is almost always much more efficient than a fossil-fired heat exchanger. Opt for modern electric machines; they generally use less energy for the same objective than a machine with a combustion source.   For example, we have shown that an 11MW electric Airtorch® for the same heating objective can replace a 16MW gas heater. Or use an electric instant steam generator instead of a conventional boiler. Or implement methods to conserve the quality of energy. 
    4. Did you know that saving 5MW of Power in a device for the same objective saves well over US$3.5 Million for the year in the cost of electric energy? More resources
    5. Upgrade equipment. Replace old furnaces and devices with the most modern emissivity heaters, crisp controls, safe insulation, and high-productivity ergonomics. Use higher temperatures for processing for the same objective to glean profits from higher productivity. Many thermal processes accelerate exponentially with Temperature.
    6. Productivity vs. Temperature (in pdf format)
    7. Clean smartly  Cleaning chemicals pack a lot of energy, but it comes from somewhere. Please keep them clean  Without adding new chemicals or contaminants. Save energy with high-temperature steam.
    8. The temperature uniformity with electric air heating is considered substantially superior to large dies’ flame heating.

      Heating Rate ProfileCompare Airtorch Heating to Flame

      Aluminum Melting Overview with MHI products

      Aluminum Melting Overview


      18 Bar

      18 Bar

    9. High Watt Airtorch

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Temperature LoPowerower (1-12 kW) HPowerower (36-400 kW)
600-1000°C LTA, VTA, MVTA(SH) MTA925 MVTA-900-(THN/DNA) Models, SH
900-1000°C (Custom), DNA MVTA-1000-(THN/DNA) Models, SH
1000-1200°C DNA, DPF, SH (CustomHigh-Pressure
re Enclosures Up to 1200°C
Resources

Continuous Overn with Airtorch

ContinuouOvenrn with Airtorch

Click here to view Typical Applications.

What’s New:: See Testimonials:: Calculate Power:: Conversion Calculator
Airtorch Flow vs. Temperature Charts:: Request a quote for Airtorch®

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Airtorch® System Introduction

Please use5-step step process for selection. First, choose the maximum rated exit temperature of the Airtorch®.  If below 900 °C, please select TA models, e.g., VTA and Mls. If above 925°C, please choose the MVTA or DPF model – please get in touch with MHI.

Sometimes, the lowest power users work through several cycles in a recuperator mode. The SH models can accept inlet gas temperatures up to 800°C. Please get in touch with MHI for details.

The Airtorch® convective system uses a particular class of elements to heat the ambient air and direct that heated air towards a surface or into a chamber. Depending on the model, the Airtorch® system can achieve temperatures ranging from room temperature to 1100-1200°C (~2200°F) with infinitely variable volume flow rates and no harmful emissions, providing a beneficial new method of heating with modern controls.

MHI Airtorch® applications are in drying electrical varnish, weld preheating, die heating, plastic softening before forming, drying motor parts, removing moisture, expansion fitting, combustion, simulation preheating and heating molds, curing, prosthetics, heat shrinking, compression molding, flock setting, curing catalysts drying slurries, freeze-drying, improving ink print finish, finishing mirror drying, latex, heating adhesives, and general heating of chambers as shown below. Add to chambers for powder and liquid finishing. Add to continuous furnaces for wood conditioning, metal finishing, and forming. A small but finite temperature drop is experienced when directing Airtorch® flow with insulated piping because of the high velocity.

  • For impingement types of applications, the DPFs offer very superior value.
  • A good rule of thumb for augmenting uniformity in an existing furnace with an Airtorch® add-on is choosing an Airtorch® power with at least 30% of the original. This may not be enough if a temperature increase is also sought.
  • When planning to extend the Airtorch® exit piping, please note that well-insulated pipes will drop the temperature very little as the exit velocity is m/s. A helpful but rough rule of thumb may be about 50°C-100°C/m drop for good internal pipe insulation. Good pipe insulation is specific to the insulation and whether the pipe is internally or externally insulated. The MHI industry standard is about a 1-2″ thick insulation. Please get in touch with MHI when required.
  • Introduction to Airtorch® | AirtorchIn Line® Applications | CalculatPowerower .vs Flow Rate | Easy Design Criterion

  • With its variable volume flow rate and power adjustability, the Airtorch™ can be set up to perform at any condition of flow temperature under the curve. Such features offer the user maximum flexibility when applying the Airtorch™ technology to heating applications.

    Easy to use selection and design page.

    Continuous Ovens.

The use of Airtorch® products may be classified into three major categories schematically drawn below.

Direct Impingement

Direct Impingement

Gas Preheating

Gas Preheating

Retrofit for Enhancement

Retrofit for Enhancement

Retrofit/Upgrading.


Use the Airtorch® with
existing furnace technology
infra-red, gas, radiant
to improve uniformity and
furnace efficiency.

   

Example of Use to Augment an Existing Furnace Installation for Improved Power and Uniformity.

An example of a 4kW Airtorch® augmentation application is schematically shown below. In this application, many complex-shaped rods are to be heated uniformly. The heat-treater reported that the rods were not uniformly heated in his existing radiant heat furnace. MHI proposed an add-on to his existing furnace with a system of Airtorch products, significantly impacting the uniformity – reducing the total energy consumed. More Green Installation and more Profits to the user. Improve oven performances and eliminate harmful emissions.


A uniform surface heating retrofit example and continuous oven examples are illustrated below.

As a rule of thumb, an Airtorch power of ~0.3 the furnace power is employed when designing for better uniformity.

Using fossil energy like fuel oil, gasoline, or natural gas for heating creates a considerable amount of CO2. The Airtorch does not use any fossil fuel nor emit any greenhouse gas.

Kilograms of CO2 emitted per Million Kilojoules from typical fossil fuels. The heat value (MJ/kg) is also shown.
Natural Gas (the main component is methane). Heat value 42-55 MJ/kg. 50.4 kg of CO2 per Million Kilojoules
Jet Fuel  Heat value 50-55 MJ/kg. 68.8 kg of CO2 per Million Kilojoules
Bituminous (coal)  Heat Value ~ 18 MJ/kg. 88.8 kg of CO2 per Million Kilojoules
Diesel and Home Heating Fuel (Distillate Fuel Oil)  Heat Value 42-46 MJ/kg. 59.9 kg of CO2 per Million Kilojoules
Gasoline and Ethanol Blends. Heat value 44-46 MJ/kg. 64.1 kg of CO2 per Million Kilojoules
  • On average, one ton of CO2 requires fossil fuel to burn and produce heat of approximately 20 million KJ.
  • One industrial process heater using fossil fuels (15MW) could use 245 Billion BTU for a year. That corresponds to a lot of CO2 production – about 12,000 tons or more of CO2 emission from one large-industrial dryer yearly!
  • The social (environmental) cost of producing/emitting CO2 gas varies from US $51 per ton (Federal Estimate) to about $185 per ton (other estimates)  (Source)
  • Thus the social cost of using a carbon-containing combustible gas could add anywhere from  25% to 100% to the price of combustion fossil fuels.
  • Did you know that  Modern Electric Heating methods  Eliminate CO2 Emissions? 
  • So why not go electric? Electric heating is also often more efficient for energy use. An excellent place to start is industrial decarbonization.

The Gamut of Airtorch Products

Airtorch 1000C

heat treating uniformity

binder burn off

A fuel’s “Heat value” is the heat released during combustion. Also referred to as energy or calorific value, the heat value measures a fuel’s energy density and is expressed in energy (Megajoules or Gigajoules) per (kilograms, kg). If the fuel contains carbon, there is CO2 emission, as shown in the table above.

 Fuel Heat value
Hydrogen (H2) 120-142 MJ/kg
Methane (CH4) 50-55 MJ/kg
Methanol (CH3OH) 22.7 MJ/kg
Propane (C3H8) 46 MJ/kg
Dimethyl ether – DME (CH3OCH3) 29 MJ/kg
Petrol/gasoline 44-46 MJ/kg
Diesel fuel 42-46 MJ/kg
Crude oil 42-47 MJ/kg
Liquefied petroleum gas (LPG) 46-51 MJ/kg
Natural gas 42-55 MJ/kg
Hard black coal (IEA definition) >~23.9 MJ/kg
  Hard black coal (Canada) ~ 25 MJ/kg
Sub-bituminous coal (IEA definition) 17.4-23.9 MJ/kg
  Sub-bituminous coal (Canada) ~ 18 MJ/kg
Lignite/brown coal (IEA definition) <17.4 MJ/kg
  Lignite/brown coal (Australia) c. 10 MJ/kg
Firewood (dry) 16 MJ/kg
Natural Uranium in LWR

with U & Pu recycle

650 GJ/kg
Natural Uranium, in FNR 28,000 GJ/kg
Uranium enriched to 3.5% in LWR 3900 GJ/kg

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A uniform surface heating retrofit example and continuous oven examples are illustrated below.

As a rule of thumb, an Airtorch power of ~0.3 the furnace power is employed when designing for better uniformity.

MHI Airtorch® Supplemental Heating Proposal
Scope: Supplement existing electrodes by applying Airtorch convective heating to increase performance and life
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Solution: By supplementing the existing electrodes with the Airtorch® and blankets, the watt density is increased on the mold, thus reducing the workload of the existing electrodes.

1 Heating: Create a convective cavity around the assembly using two 4kW Airtorch® units. Fixture Airtorch units behind mold and electrodes at angles to create air movement. This should improve the overall heating of the mold.

2 Insulation: The assembly is surrounded by refractory blankets (five sides) to retain as much heat as possible.

Add a duct heater

Extremely Compact High Power

Extremely Compact High Power Airtorch®

EFFICIENCY

Electric Systems Offer Design Improvements / Enhancements
Combustion/Flame MHI Electric Systems
Appearance Non-uniform heating – resulting in store-bought bottles varying in quality of labels. Repeatable uniform heating – resulting in consistent label results.  Once conditions are dialed in, the setup will yield minimal variation.
Bottle or Treated Surface Combustion leaves deposits on the surfaces (visible to micro level) Airtorch® or Steam or Steam/ Air patented heating leaves no combustion product on treated surfaces.  Improves detail and appeal.
Sources Combustion source creates:

Explosion hazard

Costly fuel

Emissions of CO2 from combustion

‘Hot’ spots from flame  heating

Venting required

Electric Systems:

It uses an electric line

Ambient Air or Water

No emissions

No combustion

Evenly distributed heat

No explosive consumables

SUSTAINABILITY

Modules for a Green Work Environment
Combustion/Flame MHI Electric Systems
Modularity New gas lines, more consumables used, safety approvals, etc. Modular with no hard lines needed.  You can add and subtract modules in minutes.

Easy to install

Easy to operate

Easy change of configuration

Highly mobile

Repeatability Non-uniformities seen as a result of combustion treatments on bottle surfaces.  Deposits, uneven heating, etc. Electric systems offer uniform, repeatable, and continuous treatment of products resulting in less variance.
Control Lack of precise control from combustion is a problem. Precise control of temperature and output gives high efficiency to your process.  A high level of control also allows for protection features such as overtemperature protection.