Elkem specialty and microsilica products for oilwell cementing
Elkem oilfield cementing materials: improved well integrity
Oilfield cementing involves the placement of a solid and impermeable setting material that supports and isolates the different well zones, ensuring well-integrity. Petroleum operators and their service providers use a wide array of cementing chemical additives to ensure safe and reliable cement placement across the wellbore and long-term zonal isolation. Cement must also provide support for casing/liner strings and resist deformation of surrounding areas protecting metal tubulars from corrosive gases and brines, thus preventing future collapse. During cement placement in the well, special fluids such as spacers are used to prevent downhole contamination. Cement slurries may also require accelerator or retarder additives to control the pumpability of cement, known as thickening time. Extenders or weighting agents are added to the cement blend to tailor the density of the job in each well. Other oilfield chemicals, such as dispersants, high-performance fluid loss additives or anti-gas migration prevention products or defoamers can also be added to tune the rheological slurry properties of the cement and control the fluid-loss against the potentially permeable rock formation. A properly designed cement slurry and cement operation is key to the lifespan of the well and its performance over time, complying with safety and environmental standards.
Ensuring results in oilfield cementing operations
The Elkem portfolio includes a comprehensive range of high-performance, reliable, cost-effective and environmentally safe – often PLONOR listed – specialty oilfield cement additives. This includes extenders, defoamers, fluid-loss control, gas-migration and proprietary weighting agents, as well as Microsilica-based additives to ensure that cement or resins bond to the casings and formations and provide adequate mechanical properties.
Here is an overview of our vast portfolio:
MICROBLOCK™ product is a slurrified multifunctional additive composed of sub-micron Elkem microsilica with high surface area, processed with quality-controlled particle size distribution. The Microblock™ additive prevents gas migration by decreasing the time that gas formation can flow through the cement during its set, while improving its cement bonding and mechanical properties. This is achieved by increasing the final compressive strength of the set cement and lowering its permeability, guaranteeing zonal isolation for the life of the well. Microblock also features some natural fluid-loss control.
MICROLITE™ P product is a dry sub-micron, spherical, amorphous microsilica that, due to its pozzolanic activity, creates extra binder phases resulting in lower set-cement permeability. With its lower specific gravity, it can be used as an extender, lowering cement slurry density while maintaining its required compressive strength. It lowers permeability, helps with fluid loss control and early strength development in lightweight cement systems. The pozzolanic performance improves bonding and corrosion resistance of the set cement.
MICROLITE™ L product is a pozzolanic slurry composed of amorphous spherical microsilica with high surface area, creating extra binder phases resulting in lower set-cement permeability. And, like its powder version, MICROLITE™ P, also enhances its compressive strength, lowering permeability, fluid loss and viscosity, resulting in early strength development, strong bonding, and corrosion resistance.
MICROLATEX™ is a liquid latex additive designed to block gas migration during the cement setting transition state. In addition, it is used as a general fluid loss additive in cement slurries, lowering equivalent circulating density (ECD). Its performance can be enhanced when used in conjunction with our LSG additives.
MICROMAX™ FF product
MICROMAX™ FF product is a dry weighting agent used in high pressure cementing operations. Despite its high specific gravity, its micron size makes it very easy to design very low-rheology, high-density cement slurry systems, reducing the well-known settling problem with classic weighting agents. Furthermore, the MICROMAX™ agent can be dry-blended, added to mix-water, batch-mixed or even post-added for ease of operations.
Elkem Microfibers are specialty high-performance monofilament self-dispersing fibres used to control losses and to prevent cracks in the set cement matrix. They are compatible with most cementing systems and additives enhancing the mechanical properties of set cement without affecting cement slurry performance properties.