What do you know about Hydrogen Sulphide?
Hydrogen Sulphide (H2S) is found in natural gas, animal waste, wastewater treatment, and petroleum drilling and refining. It is formed when microbial communities break down organic matter in an environment that is absent of oxygen. Colourless and extremely dangerous, in low concentrations, H2S is easily noticed by its foul odour of rotten eggs, but at higher concentration levels, it becomes odourless.
Dangers of H2S
H2S is toxic if ingested by humans and most other animals. When ingested in higher amounts, H2S can cause various side effects, such as dizziness, nausea, and even death. The various side effects that exposure to high amounts of H2S can be felt very rapidly. A few breaths at high concentrations can be lethal.
Impact of H2S in Biogas
Anaerobic digestion is a processing technology that produces biogas from various biological feedstocks in a low-oxygen environment. It is, therefore, also unavoidable that it will produce H2S. Biogas generated from AD systems contains methane (CH4) and carbon dioxide (CO2) primarily but also includes a small amount of other compounds such as H2S, nitrogen gas and water vapour.
The concentration of various components of biogas has an impact on its ultimate end use. During biogas production, the major contaminant, H2S, is toxic and corrosive. It is essential to monitor the composition of H2S levels within the reactor to ensure that pipes, equipment, and instrumentation do not begin to corrode excessively. Reducing the H2S residue content of biogas before electricity generation can significantly reduce maintenance and operational costs.
How to analyse H2S in Biogas Production
Biogas is typically used in gas engines for combined heat and power production (CHP) or in boilers for steam or power production. During combustion, the H2S will convert to sulfuric acid, and this acid destroys the engine in a very short time. It is for this reason that most biogas plants also include a H2S scrubber which removes the H2S from the gas.
In this process, it is recommended to implement a gas analyser capable of providing precise readings of H2S gas present to ensure the equipment’s safety and protection, verify scrubber efficiency, and monitor gas quality.
Using Gas Data systems for H2S analysis
There are many benefits of H2S monitoring: maintaining compliance, keeping workers safe and producing clean biogas. Gas Data has several solutions to achieve this. It could be one of our fixed Click! systems, which provides continuous data of the digester for further analysis. Or our portable gas analyser, the GFM406, which helps to monitor at more locations and verify any readings processed by the fixed analyser.
