Process and manufacturing industries require equipment for heating purposes. Heating in the industry takes place in two ways, i.e., direct heating and indirect heating. Direct heating involves the heating operation taking place directly through the combustion of fuels, heating filaments, or flame radiations. On the other hand, indirect heating involves heat transfer fluid circulating between the heater and the process. In indirect heating systems, heat from combustion sources like fuel is passed to the hot oil or thermal fluid. The heat is carried to the exchangers, such as reactor jackets, calendar rolls, platens, molds, etc. The heating system controls temperatures and supplies heat to the heat users from one primary heating unit or multiple units.
The efficiency of Thermic Fluid Heater:
Heat transfer oils are petroleum-based, either mineral or synthetic. The oil degrades as it comes in contact with high temperatures, air, or poorly designed circulation piping systems. The byproducts of degradation are soot, coke, carbon, and sludge that circulate through the overall process. It reduces the overall heat transfer efficiency, leading to higher operational costs, the danger of fire, and higher maintenance costs.
There are two primary components of a thermal fluid heater that impact its overall efficiency. The first is the design of the heater pressure vessel and the second is the burner. The thermic fluid heater is limited by the efficiency rating that drops the stack temperature below the dewpoint. The efficiency rating is usually 84% to 85%. The oil heater is fitted with an economizer to exceed 85% efficiency, which is a heat-exchange device in a boiler or thermal fluid heater that improves efficiency and saves fuel.
Pressure Vessel Efficiency:
A thermic fluid heater must harness as much heat from the combustion process as possible before the exhaust gasses exit the heater. The longer it circulates in the unit, the more efficiently the heat is transferred to the pressure vessel and later, to the hot oil. Therefore, reducing the temperature of the exhaust gasses significantly improves the efficiency. Similarly, the improved efficiency leads to using less fuel to produce the same heat in the process.
In thermic fluid heaters, two sets of coils are designed for allowing three passes of the hot gasses over the heating surfaces. Some boiler manufacturers gather additional efficiency from the hot gasses through fins on the coils and by offering stack economizers. It is particularly helpful if the plant needs heated water as the wasted heat exiting the thermal fluid heater is used for heating the water. If hot water is not required, an economizer may or may not contribute to the overall efficiency.
Burner Efficiency:
The primary function of the burner is mixing the gas and air for combustion and controlling that combustion for the firing rate to match the load. Burner efficiency is determined by mixing the gas and the air and providing an effective burn close to the burner head. Efficient burners are defined as ones that burn clean with little or no carbon monoxide (CO) and a minimal amount of excess air. Too little air leads to a burner with unburned fuel that translates to carbon monoxide.
An optimally efficient burner can achieve complete combustion with 2% to 3% of excess oxygen without releasing carbon monoxide (CO). Since CO2 is produced in the combustion process, a higher CO2 percentage leads to a lower oxygen percentage. It results in increasing efficiency.
It is also necessary to consider the burner tune or the gas/air mixture. It is imperative to bring changes in tuning between low fire and high fire for keeping the burner in perfect tune during all firing rates.
Tips to Increase the Efficiency of Thermic Fluid Heater:
Optimizing the Pump:
Pumps require the most energy as equipment in any plant and must be selected wisely. Similarly, the proper configuration of the pump can result in significant savings by avoiding operational costs. Some ways to optimize the pumps in a thermic fluid heater are:
Reducing Pressure Losses:
Pressure losses cause higher power consumption and also result in the non-optimal use of pumping systems. Some of the ways to reduce pressure losses in the different components of a thermic fluid heater are:
Using higher cross-sections in the piping to reduce pressure loss.
Pre-assembled pump systems as it has a compact design with short piping lengths to keep pressure losses in check.
Larger openings in pumps or fittings reduce the pressure losses.
Quality of Heat Transfer Fluids:
Heat transfer oils of higher quality are ideal as they are more stable. Such fuels with better heat transfer properties reduce the production time. Reduced process times result in less chances of production failures. The lowered maintenance or repair work increases productivity by minimizing the downtime of the plant.
Optimization of Firing Plant:
The overall efficiency of the thermic fluid heaters is also achieved by optimizing the firing process. By installing rotary speed controls for combustion fans, process plants improve firing efficiency and reduce start-up losses. Similarly, reducing exhaust gas losses, using air pre-heaters, controlling oxygen intake, etc., can increase the efficiency of the firing process.
Advantages of Thermic Fluid Heater:
Thermic Fluid Heater by Rakhoh Boilers:
Rakhoh is a leading name as boiler manufacturers for Steam boilers, Boiler accessories, Waste Heat Recovery Boilers, and Thermic fluid heaters for more than 38 years. Our thermic fluid heater comes in a compact, horizontal design. The 4 pass design with a proven coil ensures instant heat and automation control maintains thermic fluid temperature. It includes ID and FD Fans, Internal Air Preheaters, an Automation system, etc.
It consists of various grates, an auto-feeding system with screw feeder, and a Fluidized Bed for optimal combustion. Our Thermic Fluid Heater offers a multi-fuel firing option, optimal energy utilization, reliability, and up to 82% efficiency.
For More Info Visit : www.rakhoh.com
