Gas condensate tanks for ONE’s Q16 Maas plant development
In less than six months time, Mercon is building and erecting two storage tanks with cone roof and aluminium internal floating roof for Oranje-Nassau Energie (ONE) new build gas production facility at the Rotterdam Maasvlakte.
The tanks will be used for natural gas condensate storage, one of the products from the Q16-Maas development of Oranje-Nassau Energie BV(ONE), a Dutch E&P operator company involved in the upstream E&P industry. “It is a special project, one of a kind”, states Peter Nieuwenhuijze, Construction & Engineering Manager at ONE. In the 3rd Quarter of 2011, ONE drilled a well to reach a gas reservoir in block Q16 of the Southern North Sea. The field contains natural high caloric gas with a relatively high gas condensate content. To achieve natural gas export specification for consumers, the propane and butane fractions in the gas have to be separated. This will result in four main export products; natural gas, gas condensate, propane and butane in mixture named LPG. LPG production directly from the natural gas source makes the project special and process relatively complex.
“Besides the process complexity, there is the continuous balance between costs and schedule. Q16-Maas is considered a marginal field. Investments however are relatively high and the time frame of the project development is very tight”, Peter continues. “It is our intention to export first gas, condensate and LPG’s in 4th quarter 2013, 2 years after discovery.’’
ONE has contracted Mercon for the design, engineering, construction and transportation of the gas condensate tanks which measure 14.2m in diameter and 14.7 cylindrical height. Unloading and installation will be under the supervision of Mercon. They are experienced in building tanks off site at their own yards in steep time schedules and know how to do the job. In this way, the civil works for the tank foundation and pits can take place in parallel with the construction of the tanks, the cone roofs and the internal floating roofs. “Good interaction and flexibility are key to such a project. Mercon offers a modular approach which fits very well with our way of doing business”, says Peter.
From a safety perspective, this is also a good option as a lot of activities will be taking place at the same time at the Q16-Maas worksite. Next to the logistics process, ONE specified special safety precautions to prevent corrosion of the tanks from Mercon. The tank bottoms will be protected by a special coating of 500 micron. Also the first two meters of the lowest shell course will be treated with this special coating. Next to this, additional safety measures are required in the design of the internal floating roof to minimize emission of product to the atmosphere. A rim foam dam will prevent fire risk. Safety and environment is taken as highest priority at ONE. Mercon will use their 24/7 safety system, which is actually a behavioral safety program. It was first used for a storage tank project with Shell last year and was evaluated as very positive.
In July this year, the tanks will be shipped, installed and subsequently water tested. The tanks will be ready to receive gas condensate at the end of 2013. An ambitious target.