Thermal fluid heating is a type of indirect heating in which a liquid phase heat transfer medium is heated and circulated to one or more heat energy users within a closed loop system. Thermal oil, glycol, and water are common heat transfer mediums. The Sigma Thermal HC product line offers two types of standard thermal fluid heating system packages, the HC-1 and the HC-2. For customized needs, we offer engineered thermal fluid heaters. Contact one of our application engineers and let us help you decide which solution is right for your project.
Sigma Thermal offers standard thermal fluid heaters, custom engineered thermal fluid heaters, complete thermal fluid systems and a full range of parts and support for your process.
Typical applications
- Tank heating
- Suction heating
- Reactor vessel heating
- Process reboilers
- Platen or Press heating
- Ovens and fryers
- Natural gas heating
- Jacketed vessel heating
- Indirect steam generators
- In line liquid heating
- In line gas heating
- Heated molds or dies
- Crude oil heating
- Calendar roll heating
- Building heaters
- Autoclaves
Thermal Oil Heating Systems
Thermal oil offers the user the capability of high temperature operation (up to 600F with organic thermal oils and 800F with certain synthetics) at very low pressures. Due to the low operating pressure and properties of thermal fluids, most heaters are built to ASME Section VIII, and a licensed boiler operator is not typically required.
Many people around the world refer to these systems by different names. The phrases thermal oil heater, thermal oil system, thermal oil boiler, thermal fluid heater, thermal fluid system, thermal oil boiler, hot oil heater, hot oil system, and hot oil boiler generally all refer to the same type of closed loop liquid phase heat transfer system. Note that many people use the terms thermal oil boiler or thermal fluid boiler even though most systems do not involve any type of vaporization.
Water-Glycol Heating Systems
Due to its superior thermophysical properties, water is an ideal heat transfer medium. Closed loop liquid phase hot water or glycol solution systems are an excellent choice for indirect process heating up to approximately 300F. Because the water is used in a closed loop with no direct feed water source, heaters are typically built to ASME Section VIII and do not require a licensed boiler operator. Heaters can be built to ASME Section I when required.
HC-2 Thermal Fluid Heater
Design Features
| Range of Configurations | The HC2 can be designed in various configurations to fit your process. Heater Configuration options include vertical up-fired, vertical down-fired, and horizontal. |
|---|---|
| Classification | The HC2 can be designed to meet all area classifications and to endure harsh environments. |
| Capacities | Net output capacities are available from 500,000 to 75MM Btu/hr. |
| Advanced Control Systems | Complete control systems are engineered to optimize system safety and performance. Sigma thermal can supply simple and cost effective standard panels, as well as full process automation and PLC based combustion control / BMS. |
| Double Helical Coil Design | This design allows for three passes of flue gas along conservatively designed coil surface area. |
| Efficiencies | Base efficiencies can exceed 88% (LHV Basis) depending on process inlet temperatures, and with an optional economizer can exceed 93% (LHV basis). |
| Minimal Maintenance | Flue gasses are significantly cooled therefore eliminating the need for most internal shell insulation. This minimizes long term insulation maintenance and / or replacement. |
| Insulation | The heater shell is externally insulated with mineral wool insulation and covered with aluminum cladding. |
| Fuel Source and Burner Flexibility | Standard or engineered burner configurations are available for use with both traditional and alternative fuel sources. Low emissions burners can be supplied to meet all emission requirements (e.g., Low NOx, Best Available Control Technology). |
HC-1 Thermal Fluid Heater
Design Features
| Range of Configurations | The HC-1 can be designed in various configurations to fit your process. Heater Configuration options include vertical up-fired, vertical down-fired, and horizontal. |
|---|---|
| Classification | The HC-1 can be designed to meet all area classifications and endure harsh environments. |
| Capacities | Net output capacities are available from 500,000 to 20MM Btu/hr. |
| Advanced Control Systems | Complete control systems are engineered to optimize system safety and performance. Sigma thermal can supply simple and cost effective standard panels, as well as full process automation and PLC based combustion control / BMS. |
| Single Helical Coil Design | This design allows for two passes of flue gas along conservative coil surface area. |
| Conservative Design | Single coil design offers sturdy reliability at a lower cost than the HC-2. Generous combustion chamber size ensures no flame impingement to the coil. |
| Insulation | The heater shell is internally insulated with modular block insulation and externally painted. |
| Fuel Source Flexibility | Sigma Thermal can provide standard or engineered burner configurations for use with both traditional and alternative fuel sources. Low emissions burners available to meet all emission requirements (e.g., Low NOx, Best Available Control Technology). |
Complete Thermal Fluid Systems and Custom Engineering
For customized needs, Sigma Thermal offers engineered thermal fluid heaters and complete thermal fluid systems. With a broad range of design capabilities, Sigma Thermal can create a complete system to support any application.
Examples
- Dow A/Therminol VP-1 Vaporizer
- Pump Skid Packaging
- Temp Control Skid Packages
- Tanks & Vessels
- Exhaust Stacks
- Ladders & Access Platforms
- Fuel Train & Valve Manifolds
Economizers
With the typical elevated operating temperatures associated with thermal oil systems, it can be difficult to obtain high efficiencies in the heater alone. Sigma Thermal offers a wide variety of economizers to fit your process requirements, increase your thermal efficiencies, and lower your operating costs.
Common Waste Heat Consumers
- Combustion Air Pre-heat
- Boiler Feedwater
- Steam Ejectors
- ORC Generators
- Building Comfort Heat
- Wash Water Pre-heat
- General Process Heat
