It's possible that your area may have unpleasant odors coming from the sewers. This odor is caused by hydrogen sulfide . It's also known as sewer smell and often smells like rotten eggs. It's generated in wastewater treatment plants and the sewer system. It's usually extremely toxic to humans.
Therefore, we are going to dedicate this article to tell you everything you need to know about hydrogen sulfide, its origin and characteristics.
What is hydrogen sulfide
If you receive a complaint about odors in your surroundings, it's likely hydrogen sulfide, or the more common "sewer gas." If you smell rotten eggs near or in your home, it's most likely hydrogen sulfide (H2S). H2S is produced in wastewater treatment plants and sewer systems. Also known as "sewage gas," it is highly toxic to humans.
The presence of hydrogen sulfide in sewers is usually discovered through complaints from nearby residents experiencing odor problems. Hydrogen sulfide is formed by biological reactions in sewer systems or wastewater treatment plants. Hâ‚‚S is produced by the anaerobic fermentation of organic matter present in wastewater. The corrosion and damage that hydrogen sulfide can cause is also a significant issue in wastewater management, where it can be similar to the effects of gas and steam . Furthermore, managing this gas is essential, as it can affect infrastructure, similar to the impact of acid rain.
In the pipeline, if there is no oxygen, the microorganisms will eat and produce hydrogen sulfide, with the typical smell of rotten eggs. This is called sepsis and it is the cause of hydrogen sulfide and the stench that goes with it.
Is it harmful to humans?
Hydrogen Sulfide is a colorless, harmful gas that occurs in drains and sewers where there is no oxygen under certain conditions (called anaerobic conditions or corrosive conditions). Has an adverse effect on health. It is very irritating to the mucous membranes of the eyes and respiratory tract.
Above a certain concentration, hydrogen sulfide will numb the olfactory nerve, making it "disappear" and completely undetectable , which is one of the dangers of hydrogen sulfide. Therefore, H2S can become a problem when you least expect it. In adults, 300 ppm (parts per million) is fatal. Under certain conditions, in an enclosed space, hydrogen sulfide can be instantly deadly.
At a concentration close to 150 ppm, the sense of smell quickly becomes fatigued and the characteristic odor turns into a mild sweetness and then disappears completely. In its pure state, hydrogen sulfide can easily burn to produce a light blue flame. In other words, any leak that occurs can cause a fire.
If it is not pure, but mixed with air (under normal circumstances that cause environmental damage), it will become an explosive substance. Explosive mixtures can form at a wide range of concentrations (from 4,5% to 45,5% in air). The auto-ignition temperature, that is, the temperature at which the gas can burn even without an external source, is 250°C.
Hydrogen sulfide is found in water, oil, lubricants, and hydrocarbons (oil, naphtha, etc.). It must be remembered that the solubility of a gas in any solvent increases with pressure.
Dangers of hydrogen sulfide
In addition to emitting a unique, unpleasant odor, large quantities of H2S are irritating and especially toxic when the concentration is very high in an enclosed space. Water treatment plant personnel working in confined spaces are particularly vulnerable to this serious hazard. It is the responsibility of senior management to protect workers from the dangers of hydrogen sulfide.
Let's analyze the different levels of danger of hydrogen sulfide:
- It is a toxic gas- The poison of hydrogen sulfide has a broad spectrum. It attacks and paralyzes the nervous system and blocks cellular respiration. In high concentrations, a single inhalation can be fatal.
- It is an explosive gas: it is extremely flammable. Forms explosive mixtures with air. Contact with oxidizing products can cause fires and explosions.
- It's unpredictable: This is a harmful gas and is heavier than air. Therefore, it can accumulate in the lower parts of buildings and in pumping stations or treatment plants. It forms pockets in stagnant wastewater and creates dangerous conditions when the wastewater is displaced by the flow of pipes. Paralyzing the sense of smell prevents the body's natural protection against the gas from occurring.
How to fight this gas
One of the characteristics of hydrogen sulfide is that it corrodes sewer structures and wastewater treatment plants. In the hot, humid environment of the sewer system, H2S will oxidize to sulfuric acid. This sulfuric acid is corrosive and will corrode wastewater and wastewater treatment plants.
Erosion can occur in concrete, copper, steel, and silver in processing tanks, buildings, and electrical equipment. If precautions are not taken, pipes eventually exposed to this corrosion can rupture. Corrosion particularly affects submerged portions of pipes or drainage structures in wastewater treatment plants. Managing this corrosion is critical and may be related to the study of underwater volcanoes and their ecological impact.
The rate of corrosion depends on the amount of H2S formed and the level of preventive treatment. Now it is possible to avoid the typical rotten egg smell in the sewage treatment plants or sewage systems of our cities and municipalities.
Yara created YaraNutrioxâ„¢, a process to prevent contamination caused by oxygen depletion in sewer pipes or wastewater treatment plants. YaraNutrioxâ„¢ is Yara's unique nitrate blend, which has been tested against hydrogen sulfide in hundreds of locations worldwide. Cities such as New York, Paris, Cologne, and Montreal use YaraNutrioxâ„¢ to process the gas.
I hope that with this information you can learn more about hydrogen sulfide and why it can be dangerous for humans.
