Many oil fields in Russia are at a late stage of development, characterized by an aging stock of wells and an increase in water cut of up to 75%. These factors cause the need for repair and insulation works to eliminate stabbed overflows and sealing of production columns. Also, the urgent issue remains the increase in production from carbonate fractured reservoirs, and in the conditions of a short-term watering of the extracted products by plantar water breaking through the cracks, their effective development without conducting waterproofing works becomes impossible.
Practice shows that in the case of a repair and insulation works with a specific pick-up of an insulated interval of less than 0.8 m3 / (h • MPa), the efficiency of using a grouting mortar based on conventional oil-well cement or G grade cement is significantly reduced, since the cement consists mainly of coarse particles , which can not physically penetrate the microcracks and matrix of the porous reservoirs. For sealing violations and eliminating stabbed overflows in conditions of low injectivity, grouting mortars based on micro cement are used. Due to the small size of the micro-cement particles, the solutions obtained have a high penetrating ability, approaching in their properties to dispersion-free solutions. In many cases, the solution can even be considered as an alternative to polymeric backfill compositions.
For comparison: the particle size of a conventional oil-well cement is 40-60 microns, micro-cement is less than 15 microns. The content in the solution of a large number of small-sized cement particles (95% of the total) is a prerequisite: at a lower concentration, the solution will not be pumped into the microcrack, since in this case the movement of small particles will be blocked by larger ones.
The microcement of the brand "COLLOID 9.5", produced by Estima company LTD, completely meets the requirements of the micro cement dimension for the tamponage application, and its strength characteristics significantly exceed the majority of Russian and foreign analogues: compressive strength 24 hours - 50 KPa, 48 hours - 66 KPa.
And if you take into account the price/quality ratio of microcements produced by Estima, then the brand "COLLOID" is far ahead of its competitors.