Oilfield

Oilfield solutions

Elkem Oilfield offers a range of specialised products designed to provide superior performance and value in cementing, drilling & completion fluid applications. From microsilica products in cementing to our versatile weight materials Elkem can service your requirements.

Solutions for the oilfield

  • Completing wells using Micromax
  • An alternative to brines
  • How to drill HPHT wells
  • ECD problems in TTRD wells

A different way to complete wells using Micromax

A North Sea operator wanted to drill a sub-horizontal well to develop 2 separate reservoirs. The lower reservoir was to be produced first through 200 μ sand screens and zonally isolated from the upper sands. These would be produced much later after the higher-pressured lower sands had depleted.

A value-for-money solution was needed for a non-settling & non-damaging fluid which would be stable as a packer fluid for up to 5 years. A Micromax weighted LTOBM was used. The lower zone was produced successfully at predicted rates and after 3 years the upper zone was re-entered without any sag and put on production without problems.

Using Micromax fluids for completions and packer fluids

An operator in the Caspian required a 16.2 ppg packer fluid that was resistant to acid gases (H2S & CO2) and stable at temperatures of up to 2500F (1210C) to provide a second barrier when running completions with permanent down hole pressure gauges. The packer fluid was  needed to give extra protection if the liner top was exposed, reduce tubing movement during injection and reduce workover problems and costs.

It was identified that a weighted packer fluid was needed and that no settlement of solids must occur during the life of the completion. A Micromax weighted OBM was used. After 10 years & more than 30 wells there has been no problem pulling the original completion during workover operations.  Numerous completions have been pulled with no problems associated with settling.

How to drill HPHT wells and ultra HPHT wells

Drilling ultra HPHT wells is never easy. The operator was faced with conditions of BHST’s of over 4000 f and requiring mud densities of 18.5 to 19.5 ppg. to drill these +20,000 ft wells.

A high temperature LTOBM was chosen as the drilling fluid as brine alternatives were considered too expensive. However, prior testing using only API barite suggested that maintaining stable rheologies at such high temperatures might be difficult. There was concern at being able to manage ECD’s within the narrow margin between pore pressure & fracture initiation pressures. Haematite was considered too abrasive. A 50:50 mixture of Micromax & barite provided the right properties to drill these wells successfully.

How to drill TTRD wells more effectively

A North Sea operator wanted to produce from small, isolated fault blocks within the reservoir of a mature oilfield. TTRD offered the ability to drill low cost, short sidetracks from existing wells. However, TTRD wells result in very small annular clearances. These help to create much larger pressures losses than encountered in normal drilling and can be problematic.

Initial hydraulics modelling showed that the ECD’s on these wells would easily exceed the fracture gradients within the fault blocks & likely result in severe losses or differential sticking. Using Micromax, rather than barite, in a LTOBM reduced the ECD below the fracture pressure enabling the successful drilling of the 5 well programme

Drilling fluids

Micromax and Microdense are speciality weight materials used to produce low ECD and sag fluids, even under extreme conditions.

Stimulation

A comprehensive stimulation and acidizing product portfolio including solvents, alcohols, fatty acids, glycols, surfactants, silicones, glycol ethers, chelants, amines, and various acids.