Furnaces, pumps and robots
It is mid-fall, and it has already been six months since I started my second placement as an Elkem trainee at REC Solar. After eight exciting months at Elkem Technology it was time to move on – even if only a few hundred meters across the industry area. Although it is a common characteristic for trainees to be light on their feet, the site at Fiskaa having many of Elkem’s business areas represented has a large variety of interesting challenges to offer, and in my case staying in Kristiansand for one more period also meant that I could enjoy the beautiful summer we have had here at “Sørlandet”.
REC Solar is a manufacturer of solar modules based in Norway and in Singapore. Their production spans all the way from the raw materials of a silicon furnace, that is quartz and a carbon source such as coal, to user-end products. The plant in Kristiansand produces a high-purity silicon feedstock which is then recrystallized and processed further into wafers and modules at the Herøya and Singapore plants. The self-developed silicon purification process at Fiskaa differs from the Siemens process utilized by most other manufacturers in that it does not pass through a vaporized phase and is therefore more energy efficient, giving REC Solar’s modules the lowest carbon footprint in the world.
The production in Kristiansand is divided into five process steps. The first step as already mentioned consist of a silicon furnace much like many of the Elkem furnaces producing metallurgical grade silicon. The molten metal from the furnace is then slag treated, casted and subsequently leached in the second and third process steps. In the fourth step the leached silicon granules are re-melted and directionally solidified in a controlled manner segregating out residual contaminants, before finally the ingots are cut into blocks in the last process step. As the silicon progresses along this versatile process line and becomes progressively more refined, so are the surroundings, transforming from of a traditional smelting plant into a graceful production line with robots.
Coming from a university, with the only industrial background from R&D, working in production can at first seem chaotic – at a plant with five complex process steps and millions of components there seems to be an endless amount of information to process and to understand. People tend to be busy, and more often should rather be two places at the same time. Yet somehow, they find the time to run the plant while doing such accomplished improvement work that they keep up with the highly volatile markets of the solar industry.
From the beginning of my stay I have been working mainly towards the third process step – HYDRO – where silicon is leached in order to dissolve many of its impurities. I was given the opportunity to work on a project investigating how casting conditions in the previous process step affect the microstructure in the cast, and hence the leaching effect in HYDRO. While it is fascinating to work on such a fundamental research project so directly related to every-day production, I quickly noticed that it was only a part of the experience such an innovational and high-paced place has to offer. Therefore, I was challenged by also taking on some tasks from the plant operation by assisting the process managers.
Outside the plant I have continued living the rich trainee-lifestyle by attending numerous courses, traveling to many exotic locations and meeting many new people. Us second-year trainees have had the pleasure of meeting five new first-year trainees at our trainee gathering in Bodø, as well as saying “goodbye” to the finishing trainees starting their new positions in Elkem. I look forward to another few exciting months working at Solar before starting a new adventure during my last period as an Elkem trainee.