Bioethanol fermentation tanks built by Cital using LDX 2101

Italian steel fabricator Cital has made a decisive move towards more economical liquid storage tanks. The company has chosen Outokumpu’s proprietary lean-duplex grade LDX 2101® for 20 new fermentation tanks to be built for the UK bioethanol producer Vivergo Fuels Limited. Cital’s material choice is remarkable, as it was made solely on the basis of the material weight reduction that LDX 2101® allows compared to the traditional material in this application, austenitic 1.4301/1.4307 (304/304L). Cital managed to cut their material use by more than 15 percent. At the time when Cital made the grade selection, a sharp drop in the nickel price had made 1.4301/1.4307 competitive against LDX 2101® in absolute terms. LDX 2101® contains only 1.5 percent nickel, which is an advantage at times of high nickel prices. However, Cital found after careful calculations that LDX 2101® was the better material for them. Their choice has dramatically turned the tide for LDX 2101® in many industrial applications. The weight reduction allowed by LDX 2101® comes from the high mechanical strength of duplex stainless steel – close to 90 percent higher than that of austenitic grades. There are other benefits from LDX 2101®, including somewhat better corrosion resistance compared to 1.4301/1.4307. Because of its low nickel content, LDX 2101® also brings very welcome price predictability to projects. Cital’s first experience with duplex LDX 2101® comes from 2007, when the company used the material to fabricate liquid storage tanks for Tate & Lyle, a global renewable food and industrial ingredients manufacturer. Cital found that LDX 2101® brought them savings in more areas than one. Fabrizio Basagni, Cital’s Technical & Commercial Manager, says, “Outokumpu’s LDX 2101® is a very good alternative for the traditional austenitic grade in large-volume tanks due to the material thickness reduction. In addition, LDX 2101® brings big savings in working hours because the reduced thicknesses require less welding. There are also consequent savings in welding consumables.” Outokumpu’s 2-meter-wide coil brings additional savings in welding. Mr. Basagni also cites good technical assistance from Outokumpu as a factor in the success of the joint projects.

Coil, sheet, and plate

Outokumpu supplies one of the industry's broadest stainless steel product portfolios, in terms of grade, width, thickness and surface finish. Cold Rolled Products are used in a wide variety of end uses, ranging from providing corrosion resistant solutions for the process industry, to polished strip for consumer durables, to patterned sheet for prestigious buildings or other architectural applications. Due to their excellent dimensional tolerances and high surface quality, cold rolled products are the predominant category of stainless steels currently used on the market. Semi-Cold Rolled Products provide a surface quality similar to that found in hot rolled products, but their thickness tolerances are closer to those achieved for cold rolled products. This type of material is particularly popular for producing tubular products in both process industry and structural applications and also re-rolling. Hot Rolled Products are used in many applications in the production of process plant equipment. They are also used as feedstock in the manufacture of cold rolled flat products, tubes and bar. Our production units can supply material directly to the customer, or through one of our own service centres. The units utilise the Outokumpu network of sales companies as well as independent agents for the distribution and sale of their products. The mills also have sales personnel who co-operate closely with sales company staff and customers. Outokumpu has its own research centres that helps the sales network in product properties and their applications. The research centres are located in Avesta, Sweden and Tornio, Finland.

Duplex LDX 2101® for a Biofuel Project

Tank fabricator Oostwouder Tank- & Silobouw BV of the Netherlands chooses Outokumpu’s Duplex LDX 2101® for the company’s largest tank project to date: a farm of 66 tanks to be built for Noba Vetveredeling BV in a large-scale biofuel project in the Port of Amsterdam. The Port of Amsterdam announced a major new project on December 19, 2006: the Port has allocated nine hectares in its Westpoort zone to three Dutch companies – Noba Vetveredeling BV, Rotie BV, and Orgaworld BV – to develop a project named Greenmills for the production of biodiesel, bioethanol and biogas from recycled organic waste. Noba, a tank storage company specializing in recycled and other edible oils, plans to build in Greenmills a tank farm with an annual turnover of 600.000 tons per year, while the organic waste technology company Rotie plans to produce 200 million liters per year of biodiesel on site. Orgaworld will be producing 25 million cubic meters of biogas, partially to help fuel on-site processes. Noba’s planned level of turnover will require a tank farm comprising 66 tanks with a total capacity of 84,000 cubic meters. Noba has hired the tank fabricator Oostwouder Tank- & Silobouw BV of the Netherlands to build the farm. For Oostwouder, which has specialized in stainless steel tank fabrication for more than a decade, the new farm represents the company’s biggest project to date, estimated to consume close to 2,000 tons of Duplex stainless steel. Already experienced in the use of Outokumpu’s low-nickel Duplex grade LDX2101®, Oostwouder chose that grade for the main part of the tanks, a total of approximately 1,500 tons of the material. The decision in favor of LDX2101® was both for the high mechanical strength of the Duplex grade – close to twice that of the alternative austenitic grade EN 1.4301 (ASTM 304) – and for the low nickel content of LDX2101®. Because of recent surges in the price of nickel, LDX2101® has emerged as the more economical choice compared to higher-nickel grades. Photo courtesy Oostwouder Tank- & Silobouw BV In addition to the price advantage, Oostwouder achieved a 25% material weight saving by using LDX2101® compared to austenitic grades. Oostwouder’s Managing Director Jan Piet Oostwouder explains that tank engineering requires a certain minimum material thickness. This does not allow fabricators to take full advantage of the strength of Duplex grades, as compared to some other applications where the weight saving can be even greater. For the bottom part of the tanks, where a higher level of corrosion resistance is needed, Oostwouder uses Outokumpu’s Duplex 2304. Outokumpu has been a long-term supplier for Oostwouder. Mr. Oostwouder describes the cooperation as a good professional relationship, which has deepened in recent years as Outokumpu has emerged as the world’s leading supplier of Duplex stainless steels.

Duplex Pipes to Meet Most Stringent Specifications

In early November 2007, Sosta’s pipe manufacturing plant in Könnern, Germany is preparing to tie up close to one quarter of its annual capacity to supply welded duplex stainless steel flow-line pipes for Petroleum Development Oman (PDO). The project will facilitate evacuation of a mixture of wet gas and condensate at the rate of 1.5 to 4 million cubic meters per day from the Burhan West field to the existing Saih Nihayda Gas treatment facility for further processing and treatment. The 36-kilometer-long pipeline will pass through desert and wadis. Challenges for the project lie in implementation from concept to commissioning in the shortest possible time frame − less than 24 months. Duplex stainless steel was selected as the piping material due to presence of carbon dioxide in the wet-gas/condensate stream, and also to availability of material given the tight time frame. “This is a high-profile project both for PDO and for us,” says Edwin Saathof, Director of Sosta, a company specializing in austenitic, duplex and nickel-alloy welded pipes for oil & gas projects worldwide, including LNG plants, terminals and flow lines. Prior to the Burhan West project, Sosta has manufactured altogether 300 kilometers of duplex pipes for different oil & gas companies worldwide. The current contract, which requires pipes of 8 and 14 inches in outer diameter, is well in line with Sosta’s specialization. “Our strengths are in capabilities and know-how to manufacture large-diameter pipes, a sole focus on project deliveries, and ability to produce from both coil and plate,” Mr. Saathof says. To meet the high corrosion resistance and strength requirements, PDO pipe specifications prescribe the highly alloyed duplex stainless steel grade 2205 and a wall thickness from 5.2mm to 8.7mm. According to Mr. Saathof, the overall specifications are the most stringent applied to flow-line pipes. The duplex contract went to Outokumpu, based on a number of factors. First, Outokumpu is one of the leading producers of duplex stainless steel, both in coil and plate. Second, Mr. Saathof commends Outokumpu’s level of technical assistance and product quality, pointing out, “Partnering with Outokumpu gives a great deal of assurance to our customers.” Moreover, Outokumpu has been a steady partner to Sosta during the pipemaker’s crucial years of growth. Mr. Saathof comments on the partnership, “Sosta has quadrupled production output over the past four years. Outokumpu has supported our growth, being very reliable in terms of delivery times to keep our production running smoothly when we have been working our mill at limit.”