Essential for biogas upgrading
One of the most important renewable energies
Biogas is produced by the fermentation of biological waste products and is considered to be one of the most important renewable energies as a replacement for natural gas. Syngas is produced by gasification of a carbon-containing fuel and used as an intermediate in generating synthetic natural gas. Both gases can contain hydrogen sulphide (H₂S), which needs to be removed to prevent corrosion problems and SOx emissions. Gas desulfurization is therefore essential.
We offering several options for gas desulfurization: a pure chemical process Sulfurex®CR (Chemical Reaction), a biological process Sulfurex®BF (Biotrickling Filter), and a biochemical process Sulfurex®BR (Biological Regeneration) with integrates a bioreactor for the biological regeneration of the solvent.
What is gas desulphurisation?
Why do we have to remove H2S?
It is the process of using hydrogen gas to reduce the sulfur content in hydrocarbons thus reducing the emissions of sulfur oxides which are responsible for acid rain.
There are several technologies on the market today to remove H₂S. Equally, there are a number of aspects to consider to select the optimal technology for H₂S removal. Site conditions, gas application, operation & maintenance (O&M), capital expenditure (CAPEX) or operational expense (OPEX) are factors that have to be taken into account prior to choosing the right technology. Our specialised sales team and team of engineers are happy to assist throughout the process.
Technologies for H2S removal
Technologies to remove H₂S from biogas are referred to as desulphurisation technologies and can be allocated to one of the following categories:
- A liquid such as water or a caustic solution can absorb the H2S,
- Activated Carbon or Iron oxide-based materials are able to absorb the H2S
- Sulfide oxidizing microorganisms convert sulfur compounds into elemental sulfur is achieved through a biological process. In this process, oxygen is added.
Our specialists can offer a technology to remove sulfur tailored to the plant’s specifics and the
DMT offers a wide portfolio for gas desulfurization tailored to a plant’s specification.
H2S removal from biogas
DMT has developed a vast amount of biogas treatment technologies. For the key biogas contaminants, DMT can offer one or a combination of technologies to economically manage them. A technology selection is made by analyzing the mixture of contaminants, the gas flow, the pollution load and the application. By not pushing one technology, DMT can provide the customer with the best solution for that specific project.
Biogas is produced by the fermentation of waste from agricultural and livestock businesses, wastewater treatment plants, landfill sites, organic waste facilities or other waste producers. It is considered to be one of the most important renewable energies and it is the perfect replacement for natural gas.
Syngas is produced by gasification of a carbon-containing fuel and used as an intermediate in generating synthetic natural gas. Both of these gases can contain hydrogen sulphide (H₂S), which needs to be removed when upgrading to biomethane to prevent corrosion problems and SOx emissions. Gas desulphurisation is therefore an essential part of the biogas upgrading process.
Besides the fact that H₂S is a very toxic gas and therefore very harmful to the environment, it is also a highly dangerous gas.
The basic principle of the technologies DMT offers to desulfurize gas is the absorption of H2S into a liquid. An oxidation process converts the H2S to elemental sulfur or sulfate. DMT offers a pure chemical process Sulfurex®CR (Chemical Reaction), a biological process Sulfurex®BF (Biotrickling Filter), and a biochemical process Sulfurex®BR (Biological Regeneration) with integrates a bioreactor for the biological regeneration of the solvent.
Hydrogen Sulfide: a toxic gas
Hydrogen sulfide (H₂S) is a toxic gas that is colorless, flammable, extremely hazardous. H₂S causes a variety of issues:
- Firstly, H₂S poses health and safety risks. H₂S causes a wide range of health effects when breathing it. While the effects depend on how much H₂S you breathe and for how long, exposure to very high concentrations can quickly lead to death.
- Secondly, H₂S contributes to SOx emissions. H2S is a key component in the global sulfur cycle. It oxidizes in the atmosphere to sulfur dioxide (SO2), which can convert to sulfate through three different chemical pathways. H2S is not a climate change gas. However, because H2S can convert in the atmosphere to sulfate, it contributes to the cooling influence provided by atmospheric sulfate.
- Thirdly, H₂S is corrosive by nature. The presence of H₂S can lead to rapid and extensive damage of cogeneration engines and microturbine units. Treatment facilities, including electrical controls, instrumentation, process equipment, tankage and ventilation systems, are affected. Such corrosion results in costly, premature replacement or rehabilitation of systems reducing the overall lifecycle of a plant.
There is a high cost associated to H₂S removal technologies, predominantly based on chemical and physical processes. Therefore, biogas pretreatment contributes significantly to the overall operation and maintenance costs of any energy recovery system.