High Purity THT for Gas Odorization - Qingdao Zhongshitiancheng
Created on 07.27
Gas Company Safety - Gas Odor Additive
Where Does the Rotten-Egg Smell in Gas Come From? A Complete Guide to Gas Odorants Safeguarding Household Gas Safety
Natural gas and liquefied petroleum gas used for daily cooking and heating are colorless, odorless and non-toxic by nature, yet highly flammable and explosive. Once gas accumulates in confined spaces and reaches the lower explosive limit, open flames or static electricity can trigger deflagration. Numerous past gas safety accidents stem from undetected odorless gas leakage. The pungent smell people perceive does not belong to gas itself, but artificially added gas odorant, the first warning line for household gas safety.
1. Core Function of Odorants: Olfactory Warning to Prevent Explosions
China's Code for Design of City Gas Engineering enforces a mandatory standard: people must distinctly detect gas by smell when non-toxic gas leaks to 20% of its lower explosive limit. Taking natural gas as an example, its lower explosive limit is 5%, meaning leakage at 1% concentration must be perceptible in advance to eliminate explosion risks.
Thanks to the extremely low olfactory threshold of odorants, leaks can be detected at an early subtle stage. Their sensitivity even surpasses gas alarms: slow minor leaks are hard for detectors to capture, while human noses can spot hidden dangers promptly with the help of odorants.⚠️ Important Reminder: Olfactory warning, gas alarms and natural ventilation cannot replace one another; multi-layer protection maximizes safety.
2. Mainstream Odorants on the Market & Safety Analysis
- Tetrahydrothiophene (THT)
The most widely adopted mainstream odorant for urban gas pipeline networks in China. It is pale yellow transparent liquid with garlic-like irritating odor. It features stable chemical properties, resisting oxidation and adsorption loss during long-distance pipeline transportation, and causes no corrosion to steel pipes, valves or gas meters. Its combustion products are stable, and legally dosed THT is harmless to human bodies. It has become the global standard raw material, with conventional dosage of 15~30mg/m³.
- Ethanethiol
Widely used in early times for its intense odor and ultra-low olfactory threshold. Nevertheless, it is unstable, prone to attenuation during long-distance transportation and corrosive to copper pipe fittings. It has been gradually phased out from urban pipeline networks in China and is only used in scattered small-scale scenarios.
- New Sulfur-Free Eco-Friendly Odorants
New upgraded products developed amid low-carbon transformation. They contain no sulfur, cause no corrosion and produce no sulfide emissions after combustion, perfectly fitting hydrogen-blended natural gas and hydrogen supply systems, representing the future upgrading direction of the industry.
Frequently Asked Questions (FAQ)
1. What is tetrahydrothiophene and what is it used for?
Tetrahydrothiophene (THT) is a sulfur-containing organic compound used primarily as an odorant for natural gas, LPG, and other combustible gases. Its strong, unpleasant smell allows people to detect gas leaks quickly, significantly improving safety in residential, commercial, and industrial environments.
2. What is the purity level of the tetrahydrothiophene supplied by Qingdao Zhongshitiancheng?
Our tetrahydrothiophene is produced with a minimum purity of 99.5%, verified through rigorous gas chromatography and other analytical testing methods. This high purity ensures consistent odorization performance and compatibility with gas pipeline infrastructure.
3. How is tetrahydrothiophene added to natural gas?
Tetrahydrothiophene is injected into natural gas streams using specialized odorization equipment such as drip-feed odorizers, bypass odorizers, or direct injection systems. The typical dosage rate ranges from 5 to 20 parts per million depending on gas composition, distribution conditions, and regulatory requirements in the target market.
4. Is tetrahydrothiophene safe to handle and transport?
Tetrahydrothiophene is a flammable liquid that requires proper handling precautions including adequate ventilation, personal protective equipment, and storage away from heat sources and oxidizers. When handled according to safety data sheet guidelines and transported in compliant packaging, it can be managed safely by trained personnel.
5. What packaging options are available for tetrahydrothiophene purchases?
We offer three main packaging options for tetrahydrothiophene: 200-liter steel drums for small to medium volumes, 1,000-liter intermediate bulk containers (IBCs) for medium to large volumes, and bulk tanker shipments for high-volume industrial consumers and gas utility companies requiring cost-effective logistics.
6. Can tetrahydrothiophene be used in cold climate gas distribution systems?
Yes, tetrahydrothiophene performs reliably across a wide range of temperatures, including cold climate conditions. Its favorable vapor pressure characteristics ensure that adequate odorant concentration is maintained in the gas stream even during winter months when pipeline temperatures drop significantly.
7. How does Qingdao Zhongshitiancheng ensure consistent quality across different production batches?
We maintain an ISO-certified quality management system with strict process controls, in-house laboratory testing using advanced analytical instrumentation, and detailed batch documentation. Every batch is tested for purity, moisture, density, and odor performance before release, and non-conforming batches are quarantined immediately.
8. What is the typical lead time for tetrahydrothiophene orders?
Standard lead times range from 7 to 21 days depending on order volume, packaging requirements, and destination. Our logistics team works to accommodate urgent orders whenever possible, and we maintain strategic inventory levels to ensure supply continuity for our regular customers.
9. Does Qingdao Zhongshitiancheng ship tetrahydrothiophene internationally?
Yes, we export tetrahydrothiophene to clients across Asia, Europe, Africa, and the Americas. Our team handles all international shipping documentation, customs clearance, and regulatory compliance requirements to ensure smooth delivery to your designated port or facility.
10. How does tetrahydrothiophene compare to ethyl mercaptan as a gas odorant?
Both tetrahydrothiophene and ethyl mercaptan are effective gas odorants, but THT offers superior chemical stability, a more consistent vapor pressure profile, and better resistance to oxidation during storage. These characteristics make tetrahydrothiophene a preferred choice for many long-distance gas distribution networks and odorization systems requiring predictable performance over time.
Contact
Leave your information and we will contact you.