THT Monitoring / 2026-09-24
Article Summary
Select an online THT analyzer by defining the odorant, sampling location, required concentration range and units, sample conditions, maintenance plan and receiving data system. THT means tetrahydrothiophene. An analyzer for this odorant serves a different purpose from a methane leak detector. A useful quotation must specify the sampling arrangement and included equipment as well as the analyzer itself. Confirm which sampling accessories, communication options and commissioning services are included before comparing costs.
What must be defined before comparing analyzers?
Start with the measurement task. A station monitoring project and a comparison of several network sampling points need different scopes. Record what the operator will do with a low, high or missing result; this helps distinguish measurement requirements from reporting preferences.
- Identify THT or the actual odorant blend; do not assume a THT instrument measures every component.
- State the expected range and reporting units, including any reference conditions used by the receiving system.
- List the sampling points and whether each needs its own instrument or another confirmed sampling arrangement.
What should the sampling package include?
Treat the sample path as part of the project specification. Hanwei describes a sampling-based installation for its online THT analyzer. It should not be selected as a direct inline section of the gas main. The proposed design needs review against the actual site.
- Provide process pressure, sample connection information and the intended analyzer location.
- Ask the supplier to identify pretreatment, carrier gas if required, sample handling, utilities and installation responsibilities.
- Confirm the complete measurement cycle and maintenance access rather than comparing headline response figures alone.
How should calibration and operation be evaluated?
Request the model-specific calibration procedure, consumables list and service requirements before ordering. Agree how unavailable or invalid readings will appear in operating records. Concentration records alone do not establish compliance with every local odorization requirement.
- Ask which reference materials, checks and replacement items the quoted configuration needs.
- Confirm who performs commissioning, routine checks and fault investigation.
- Define the acceptance records and the site conditions under which the proposed performance will be assessed.
What should go into a quotation request?
Send the target country, odorant details, sampling point information, range and units, number of points, available utilities and receiving system. Hanwei can review the online THT analyzer against that scope. Ask for confirmed range, accuracy, certification evidence and a list separating included equipment from options.
- Identify the required data interface and alarm-handling workflow.
- Request a sampling arrangement drawing and maintenance information.
- Record unresolved requirements explicitly so competing quotations can be compared on the same basis.