Geothermal

Geothermal energy is heat from within the earth which, once extracted, can be used for heating or to generate electricity. It is a low cost source of renewable energy, providing a consistent base load energy source 24 hours per day, 7 days per week, with minimum environmental footprint.  The most active geothermal resources are usually found along major tectonic plate boundaries, notably on the west coast of the United States and South America, in the Pacific Rim, in continental Europe and in Africa. 
Vallourec has over 30 years of experience in geothermal projects around the world. Here are some examples: 

Challenges

Geothermal energy resources are concentrated at the margins of the earth’s tectonic plates, in regions subject to earthquakes and volcanoes where steam production temperatures may be in excess of 250°C. To ensure the integrity of geothermal wells, the well design needs to take into account various reservoir parameters:  




Solutions 

High temperature
As temperature increases, the yield strength of materials decreases and compression loads on cemented tubulars increases. We offer: 
  • Proprietary higher yield strength materials
  • Proprietary connections which offer better compression resistance to compensate thermal expansion along the string, such as DWC/C, DINO VAM, VAM TOP®
  • VAM® 21 premium connections are as strong as the pipe and allow full compression to compensate thermal expansion along the string 
  • Sealability of VAM® connections is tested at high temperatures (gas tight for premium, liquid tight for semi-premium) 

Corosion - presence of H2S and CO2
  • We offer a wide range of corrosion resistant steel grades from carbon steel sour service grades to alloy grades

Flow rate
  • VAM® connections have flush ID which prevents flow turbulence and errosion along the inside of the pipe

Unstable formations
Reaming through unstable formation increases the need for high torque connections and high collapse grades:
  • VAM® high torque connections can be used for drilling (drilling with casing)
  • The wide range of VAM® connections ensures better sealability performances and torque control than API BTC connections

Product lifetime
  • Vallourec offers large grade portfolio and technical support on material selection for the best economical solution for the lifetime of the geothermal reservoir 

Cost efficiency
  • Our Vallourec Global Solutions are adapted to meet your needs; from well design to supply chain solutions and field support for greater project efficiency.
  • VAM® connections allow fast running to save rig time    

Selecting the right connection for your production well



The Gas Storage is here the storage of Natural Gas used for domestic and industrial applications in an underground facility. Gas storage is principally used to meet load variations. Gas is injected into storage reservoir during periods of low dem​and and withdrawn from reservoir during periods of peak demand.

Different types of underground geological storage facilities exist. It can be either a natural geological formed cavern (depleted fields, salt caverns, aquifers) or it can be a man made cavern (abandoned mine).

  • ​​Aquifer is an underground layer of water-bearing rocks. Water-bearing rocks are permeable, and can be reconditioned for gas storage.
  • Depleted reservoir storage utilizes a depleted underground natural gas reservoir that originally contained oil and/or gas.
  • Salt cavern is based on underground salt formations (salt domes or bedded rock salt deposits). These geological formations are well suited to natural gas storage. Cavern storage consists of artificially created cavities in the salt formation. The digging dissolution (Using water injection process also called leaching) is the method used to create the cavities. Once created, a salt cavern offers an underground natural gas storage vessel.

Gas Storage is mainly onshore due to the costs of development and constraint to transport natural gas from storage facility to the transportation network (and vice versa)

The number of wells and well design depend on the type of underground reservoir:

Depleted fields are attractive because their geological and physical characteristics have already been studied and are usually well known. This kind of reservoir generally allows to re-use part of existing wells with suitable modification. Aquifer reservoir and salt cavern require installation of new wells (about 8-10 wells per site).

Challenges

Drilling operations are realized using the classic oil & gas drilling technique and well architecture is based on standard well design.

 Salt cavern reservoir is generally the most critical case due to the two-stage process with a first long (can last several years), and expensive "leaching operation" to create the cavity. This operation can generate corrosion problems and crystallization associated with the brine. Structurally, and due to heterogeneity of the rock types, cavern created within bedded salt formation is also more unstable and the creep of rock salt resulting can generate external pressure to the completion casing.

In all cases, the casings must have the quality required to ensure a longer service life and are generally being tested for tightness.  For completion, production casings and liners require premium connections gas tight.

​Solutions

For all these different cases, from standard application to more severe environments, Vallourec offers a full range of premium connections and proprietary grades.

Vallourec Global Solution can help you selecting the most appropriate connection and material for your application based on field experience gained thru years of services for Oil and gas industry including gas storage application.

The worldwide network of VAM® Field Service provides the best in class services and expertise for VAM® connections running supervision, supporting our clients for make-up and inspection services.

 

Brochures​​

​​OCTG Product Selection Guide​​​​​​​​​​​​
​​Geothermal applications​​​​​​​​​​​​