Oil and Gas Field Souring Forecasting and Mitigation
Predict, monitor and mitigate field souring with tailor-made solutions.
Understanding the source and future development of hydrogen sulfide (H2S) is critical for identifying suitable mitigation options. Over half of the world’s remaining hydrocarbon resources are contaminated with carbon dioxide and/or hydrogen sulfide, and reservoir souring has a significant economic impact. H2S can be generated by sulfate reducing microbes in the reservoir or facilities during production or can be naturally generated over geological time via various processes. Each generation mechanism requires a different monitoring and mitigation strategy.
Benefits of SGS H2S services
At SGS, we can help you to effectively mitigate reservoir souring. Combining innovative technology and integrated studies, we provide bespoke mitigation strategies based on state-of-the-art sampling and laboratory workflows, forecasting and modeling. Our H2S services include:
- Tailored H2S measuring methods
- Monitoring and sampling in fields or at facilities:
- Microbial sampling & monitoring
- ISOTRAP sampling
- Gas and fluid sampling
- Laboratory analyses:
- Sulfur isotope ratio analysis (SIRA)
- Microbiology – growth and kill test
- Molecular biology – various DNA methods
- QEMSCAN – mineralogical evaluation
- CSIA – compound specific isotope analysis
- H2S partitioning studies
- Data interpretation
- Data gap analysis and sampling programme design
- H2S modelling and history matching
- H2S forecasting
- Mitigation screening, optimisation and monitoring
Our technology provides focused H2S mitigation at the subsurface level and during surface transportation, storage and shipment. Using proven workflows, which integrate data from a variety of disciplines, our experts deliver integrated souring assessments and create models for the H2S generation, propagation and development within reservoirs, wells and surface facilities.
Tailored H2S Studies
We use commercial modelling software in combination with proprietary workflows to forecast H2S generation on geological and field production timescales. Our clients receive H2S mitigation options tailored to their field development. Each comprehensive study comprises multiple scenarios and forecasts to assess the uncertainties of H2S generation, movement and migration. The H2S models incorporate geological, microbial, geochemical and mineralogical data, as well as thermal and maturation history, fluid regions, pressure regimes, production data and reservoir properties.
Our microbiology and DNA sampling and analysis expertise assures that you benefit from greater accuracy in terms of characterising sulfate reducing bacteria (SRB) and archaea (SRA). We have extensive experience of performing microbial analysis via the most probable number (MPN) method, adenosine triphosphate (ATP) or adenosine phosphosulfate (APS). Our microbiology laboratories use special sampling kits to make the distinction between sulfate and nitrate reducing bacteria and general heterotrophic bacteria. We also carry out DNA analysis of water samples, solid samples and incubated cultures. DNA technology is used to identify and characterise the bacteria present in a sample. This analysis is done using state-of-the-art Next Generation Sequencing (NGS) techniques.
Why should you depend on SGS to perform field souring studies?
Our field souring studies can help you:
- Identify the most optimal and cost-effective mitigation strategy
- Understand future H2S levels developments and plan accordingly
- Plan your field (re)development with a strategy around H2S
- Understand the risk of encountering H2S in new prospects during exploration
- Conform to HSE and (sour service) material selection guidelines/regulations
- Design a complete monitoring programme to minimise risk of unplanned production downtime
Integrated and innovative approach
Our innovative approach in modeling and forecasting allows for a more efficient and cost-effective H2S mitigation strategy. Prior to any numerical simulations, material balance tools are used to validate multiple scenarios. Our in-house material balance tool takes into account sulfur sources and sinks as well as produced and remaining sulfur in a reservoir. This allows us to determine whether the mechanisms considered in a scenario can produce the observed quantities of H2S. Numerical reservoir souring models can be used to validate the origin of H2S from analytical analyses and interpretations.
Subsequently, using a commercial reservoir simulator a calibrated souring model is matched to historic H2S observations. This reduces uncertainty in future H2S production forecasts and allows a wide variety of souring mitigation strategies to be tested.
The benefit of the SGS method is that sensitivity analysis can be easily performed and calibrated to specific well configurations and sectors, or to a full-field model. Moreover, reservoir development and management scenarios, such as changes to injection, production rates and patterns, recompletion and surface compression, can easily be evaluated with regard to H2S development and production.
The H2S mitigation strategies that are explored are thus not only the typical biocide, nitrate or scavenger dosages, but we can also evaluate the impact of:
- Alternative injection patterns
- Different injection rates
- Changes in injection water compositions
- Impact of EOR technologies
- Surface compression optimisation
- Gas lift scavenger dosages
Contact us today to find out how we can help you understand, forecast and mitigate the H2S in your assets.