Description
Custom Electrically Heated Tubing Bundles for CEMS and Process Analyzer Applications
Thermon Custom CEMS and Analyzer Sample Lines are engineered electrically heated tubing bundles designed for demanding Continuous Emissions Monitoring System (CEMS) and process analyzer applications. They are particularly suited to high-temperature extractive emissions monitoring and mercury (Hg) CEMS applications, where maintaining the sample at the required temperature is critical to reliable analysis.
Thermon combines process tubing, electrical heat tracing, insulation, temperature sensing and optional conductors into a customized tubing-bundle assembly. This approach provides a pre-engineered solution for transporting samples from the sampling point to the analyzer while helping maintain the required thermal conditions along the sample line.
Key Features
- Custom-designed CEMS and analyzer sample lines
- Electrically heated tubing bundle construction
- Designed for high-temperature extractive CEMS applications
- Suitable for mercury (Hg) monitoring
- Suitable for ammonia (NH₃) slip monitoring
- Applications including flare CEMS
- Multiple tube materials and sizes
- Optional auxiliary conductors
- Factory-installed temperature sensors
- Multiple heat-tracing options
- Special markings and identification available
- Custom bundle configurations
- Solutions for hazardous/classified locations are available
- Cut-to-length manufacturing
- Application-specific design data available.
What Is a CEMS Sample Line?
A CEMS sample line transports a representative gas sample from the sampling location to the analytical equipment.
The sample must be transported under controlled conditions so that condensation or changes in the sample composition do not compromise the measurement.
Thermon’s heated tubing bundles are designed to help keep the sample line at the required temperature. In CEMS applications, heated umbilicals or heated transport bundles are commonly used to keep gas samples above their dew point during transport.
This is particularly important when monitoring emissions from industrial combustion and power-generation systems.
Custom Design for CEMS Applications
One of the main advantages of Thermon’s CEMS solution is its custom manufacturing capability.
Rather than using a single standard tubing configuration, the bundle can be engineered according to the requirements of the application.
Thermon’s flexible manufacturing process can incorporate:
- Process tubes
- Auxiliary electrical conductors
- Non-heated tubes
- Factory-installed temperature sensors
- Electrical heat tracing
- Special identification markings
- Different insulation configurations
- Different outer-jacket materials.
This allows the tubing bundle to be configured around the actual analyzer system and installation environment.
Tube Materials and Finishes
Thermon provides a wide selection of tubing materials for Custom CEMS and Analyzer Sample Lines.
Available materials include:
- 316 stainless steel
- 304 stainless steel
- Monel
- Titanium
- Alloy 825
- Fluoropolymer tubing
- PFA
- TFE
- FEP
- Nylon
- Polyethylene
- Composite filament-wound tubing.
Tubing can be supplied in welded or seamless configurations depending on the application.
Optional surface finishes and treatments include:
- Electropolishing (EP)
- Chemical passivation (CP)
- SilcoNert®1000
- SilcoNert®2000
- Dursan®.
These options allow the tubing material and internal surface to be selected according to the sample chemistry and analytical requirements.
Multiple Tubes in One Bundle
Thermon can incorporate multiple tubes into a common bundle.
This can include:
- Heated sample tubes
- Non-heated sample tubes
- Different tubing materials
- Auxiliary conductors
- Instrumentation wiring
- Temperature-sensor wiring.
Double-containment tubing and multiple tube materials can also be incorporated into a common bundle where required.
This makes the system particularly useful when several sampling or instrumentation lines need to run between the same two locations.
Electrical Heat Tracing
The sample line can incorporate Thermon’s electrical heat-tracing technologies to maintain the required sample temperature.
The Custom CEMS brochure identifies options including SX self-regulating heat tracing and HPT power-limiting heat tracing. These systems can be cut to length in the field while maintaining temperatures up to 350°F (177°C) for the referenced configurations.
The appropriate heat-tracing system depends on:
- Required maintenance temperature
- Maximum exposure temperature
- Sample properties
- Ambient conditions
- Bundle length
- Installation environment
- Hazardous-area classification.
Embedded Temperature Sensors
For sensitive analytical applications, Thermon can install temperature sensors directly into the tubing bundle during manufacturing.
Available sensor types include:
- RTD
- Thermocouple
- Thermistor
Factory-installed sensors can be positioned to accurately sense temperature at one or more locations along the bundle. Thermon documentation specifies insulated sensor leads rated up to 500°F (260°C) for the referenced configurations.
This integrated approach can simplify temperature monitoring and improve control of critical analyzer sample lines.
Temperature Control and Monitoring
Maintaining a stable temperature is particularly important for analytical sample lines.
Thermon’s control and monitoring solutions can be used with the heated tubing bundles. The referenced systems utilize 3-wire RTD temperature sensors and can provide:
- Single-point temperature control
- Multi-circuit temperature control
- Temperature monitoring
- Electrical-current monitoring
- Ground-leakage protection where required by code.
For a local single-point application, Thermon also identifies the ECM electronic control module as a control and power-junction solution.
Hazardous-Area Applications
CEMS and analyzer systems are often installed in industrial facilities where hazardous-area requirements must be considered.
Thermon’s Custom CEMS documentation identifies electrically heated TubeTrace® solutions approved for hazardous/classified locations, including configurations for:
- Class I, Division 1
- Zone 1
The exact certification and heat-tracing configuration must be selected according to the applicable hazardous-area classification and project requirements.
Applications
Thermon identifies several important applications for its Custom CEMS and Analyzer Sample Lines.
Flare CEMS
Heated sample lines can be used to transport samples from flare monitoring points to the analyzer while maintaining appropriate sample conditions.
Mercury (Hg) Monitoring
Mercury monitoring is one of the demanding applications specifically identified by Thermon. Maintaining the correct sample temperature is important for reliable extractive monitoring.
Ammonia (NH₃) Slip Monitoring
Custom analyzer sample lines can also be designed for ammonia slip monitoring, another application identified in Thermon’s CEMS documentation.
Power Generation
CEMS sample lines are widely used in combustion and power-generation facilities where emissions must be continuously monitored.
Industrial Process Analyzers
The same tubing-bundle concept can be applied to process analyzers where temperature-sensitive samples need to be transported over long distances.
Why Heated Sample Lines Are Important
A sample line can significantly affect the quality of an analyzer measurement.
If the sample temperature falls below the required dew point, condensation can occur inside the tubing. This can alter the sample composition and potentially affect analyzer accuracy.
Thermon’s application literature describes heated transport bundles as a means of keeping gas samples above their dew point during transport.
For CEMS systems, therefore, the tubing bundle is not simply a means of transporting the sample. It is part of the overall sample-conditioning and measurement system.
Custom CEMS Sample Line Construction
A typical Thermon custom bundle may incorporate:
| Component | Function |
|---|---|
| Process Tube | Transports the sample |
| Heating Cable | Maintains required sample temperature |
| Insulation | Reduces heat loss |
| Temperature Sensor | Measures bundle/sample-line temperature |
| Auxiliary Conductors | Provides power or signal connections |
| Outer Jacket | Protects the bundle from the environment |
| Special Marking | Identification during installation and maintenance |
The exact configuration is customized according to the application.
Technical Specifications
| Attribute | Specification |
|---|---|
| Brand | Thermon |
| Product Type | Custom CEMS & Analyzer Sample Line |
| Product Family | Electrically Heated Tubing Bundles |
| Application | CEMS / Process Analyzer |
| Heating Method | Electrical Heat Tracing |
| Tube Materials | 316 SS / 304 SS / Monel / Titanium / Alloy 825 / Fluoropolymer / Others |
| Tube Options | Welded / Seamless |
| Surface Finish | EP / CP / SilcoNert® / Dursan® options |
| Heat Tracing | SX / HPT and other application-specific options |
| Temperature Sensors | RTD / Thermocouple / Thermistor |
| Sensor Lead Rating | Up to 260°C for referenced configurations |
| Hazardous Area | Selected Class I Div. 1 / Zone 1 configurations |
| Maximum Temperature | Application/configuration dependent |
| Bundle Configuration | Custom |
| Applications | Flare CEMS / Hg Monitoring / NH₃ Slip / Process Analysis |
Exact temperature, electrical rating, tubing dimensions and heat-tracing selection should be specified according to the actual application and Thermon’s engineering documentation.
Advantages of Thermon Custom CEMS and Analyzer Sample Lines
Custom Engineering
The bundle is designed around the customer’s process and analyzer requirements rather than being limited to a single standard configuration.
Integrated Construction
Tube, heat tracing, insulation, temperature sensing and optional conductors can be incorporated into a single assembly.
Reliable Temperature Maintenance
Electrical heat tracing helps maintain the required sample-line temperature and can help prevent condensation during sample transport.
Material Flexibility
A wide selection of metallic and fluoropolymer tubing materials allows the bundle to be matched to different sample chemistries.
Easier Installation
A factory-assembled tubing bundle reduces the need to install and assemble individual tubing, heat tracing and insulation components separately in the field. Thermon also identifies cut-to-length and pre-engineered bundle solutions as benefits of its tubing-bundle approach.
