When replacing combustion heating with electrical heating, one should compare the energy efficiency, use of modern electronic controls, and the choice of materials used to construct the device for life calculations.
It is necessary to choose electric devices that use less energy (i.e., waste less energy) that replace combustion devices. Not all electric devices are the same. Even if they offer the same efficiency – for example – some may use less pressure, such as in-process air gas heaters like the Airtorch. Higher pressure drops correspond to significant wasted energy. Some may not offer warranties on heating elements. A better warranty equates to less downtime.
The low-pressure drop feature makes them convenient to use with fans for comfort heating and drying.
Decarbonization is easy with any Airtorch.
Preheating with an Airtorch is often much more energy efficient and, of course, cleaner than combustion.
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 to choose an Aitorch® power with at least 10-30% of the original furnace power for a direct electrical substitution in an electric furnace.
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.
Someaugmentions ideas are shown in the graphic below.
Positioning of the Airtorch® can be at any place that gives the best uniformity. Although this changes with the size and shape of the chamber, it has been our experience that positioning the Airtorch-to-furnace opening/inlet closer to the furnace roof provides the best uniformity.
Please adjust the calculated power required if operating at the maximum rated temperature and unsure about piping insulation. t is also essential when working close to the rated maximum temperature of an Airtorch® to employ all flow and temperature alarm systems, e.g., low-flow, over-temperature, and other features. The MHI control Panels are configured to be responsive to the alarm condition. Please adjust the power required to consider any losses in your delivery piping. The availability of flanged outlets or NPT Exit Nozzles depends on the chosen model. Almost all models accept user-provided blower or compressor-driven air/gas input. Not all models can use fans. Fans are employed when the drop in pressure of the system is no greater than approximately 50 in. w.c. Fifty in. w.c./inches of H20 is about 1.8 psi.). This condition remains true even when the fan can output large CFM values. The Airtorch® models by themselves have a low-pressure drop.
DPFs, HI, THN, GTAs, LTAs, MVTAs, and VTAs should be used with an MHI power control system. The power controller offers the possibility of reducing power and flow together when used with a proper control system for power management. Note that each Airtorch® will lose heat through the nozzle or body and the downstream piping when used. Please consult MHI for the efficiency of your particular model. Although MHI Airtorch® models are highly efficient in power conversion, it is prudent to plan for a slightly higher power than that determined by the equation or graph. In addition, if excess heat is lost from the exit nozzle, prepare for a higher power unit than the abovementioned equation. Note: the loss in efficiency typically depends on the use and manifolding. Please contact MHI for assistance.
Please consult with MHI on the best solution for your industrial process gas or inline heating. Please consult MHI on the correct system for your application. MHI Airtorch® models also offer a low-pressure drop. MHI Airtorch models are designed with high efficiencies in mind. If the flow of 1~1.2 kg/s is driven with 10 Bar pressure as opposed to low pressure (Airtorch® type), then almost ~1 MW of power may be wasted for just driving the flow! So please compare this power loss for pressure flow when comparing manufacturers.