Oil Reservoir Souring
Preventing reservoir souring is essential to maintain the value of oil reservoirs and fight corrosion in pipelines. See how PetroCare helps.
Every day, the leading oil service companies rely on Yara’s PetroCare to control biological hydrogen sulphide (H₂S) formation, prevent acidification in the oil tank, and to optimise drilling fluids.
PetroCare works by preventing the biological formation of H₂S, through stimulation of natural processes. It is an environmentally friendly solution in comparison with alternatives available on the market.
Yara's H₂S reduction solutions for the oil industry:
Independent academic reports, laboratory and field tests recommend nitrates to reduce H₂S formation and help improve work safety.
Biological reservoir souring happens when water injection is used for secondary oil recovery, especially in offshore installations where sulphate-rich seawater is used. The lack of oxygen, warm temperatures and the presence of sulphate, stimulates naturally-occurring microbes, which then produce toxic H₂S. This turns sweet oil to sour.
Sour oil has a lower market value and the presence of H₂S gas at the producer can lead to:
PetroCare is dosed into the injected seawater. This encourages the microbes to generate harmless nitrogen gas – instead of the harmful sulphide produced when sour conditions prevail.
Specialty nitrates like PetroCare change the bacterial environment, so that they no longer produce sulphide gases. Nitrate is a natural substance present in soil, where it is a major nutrient for plants. Yara’s nitrate-based technology is, therefore, a natural, environmentally friendly way to eliminate the problems caused by H₂S.
Selection of an acceptable drilling fluid is now increasingly linked to environmental legislation on waste management, cost savings, as well as traditional technical aspects. Disposal of waste drilling fluids and associated contamination is becoming a concern worldwide.
Operators adapt by developing and following waste minimization, recycling and bioremediation strategies. In addition the right choice of drilling fluid will increase Rate of Penetration (ROP) of the bit and therefore total drilling depth is increased. These are some of the reasons why the leading oil service companies have come to rely on Yara’s environmentally-friendly PetroCare in drilling fluid.
Yara’s knowledge of nitrates has allowed our experts to develop speciality nitrates that can be added to drilling mud (fluid).
If you want help with combatting biological reservoir souring or a quote for PetroCare to use in drilling fluids, contact us.
PetroCare replaces calcium chloride, sodium bromide or formate salts in the internal phase. It provides an environmentally friendly solution and reduces waste management issues and related costs. The wide range density PetroCare offers also gives operators the flexibility to use it as mid-range density brine.
PetroCare can be used as an inorganic flocculant. This application is linked to reactive clays with a high rate of penetration (ROP). Using it this way prevents bit balling and flowline plugging. PetroCare contains calcium nitrate, which is classified as a "medium clay inhibitor". Water resulting from dewatering process can be used as a base for preparing other mud systems.
PetroCare acts as an inhibitor of sulphate-reducing bacteria during fracturing processes. Speciality nitrates are added, in addition to biocide products. Biocide is included to protect guar gum and reduce biofilms.
PetroCare can be used as cementing additives to help operators meet strict criteria of thickening time in cementing jobs including steam-injection slurries. PetroCare cementing additives increase the early compressive strength (up to 8 hours) and decrease wait on cement (WOC) time reaching 50 and 500 psi.
The use of PetroCare cementing additives drastically reduce slurry sedimentation, free fluid and cement fall-back. In addition, the overall well safety, well integrity and quality of cement job can be improved and eventually demand for any remedial job reduced.
Thanks to PetroCare, you can determine the presence and extent of possible damage of core samples by invasion of the mud or filtrate from the mud.
Liquid and solid waste where PetroCare has been used can offer a greener solution for waste disposal. For example, Canada has a program for using bioremediation techniques (land farming) to help deal with waste soil by creating various conditions to stimulate aerobic microbial activity. Using Calcium Nitrate in place of calcium chloride offers several advantages:
Nitrates can stimulate bio-reactors used to process waste materials and therefore give a higher output from the process.
The safety data sheets for our products are produced in accordance with current regulations and outline the risks associated with the use of our chemicals.