Bayer MaterialScience TDI Plant, Germany
Key Data
German-based polymer and plastics producer Bayer MaterialScience is planning to construct a new toluene diisocyanate (TDI) plant at its Chempark site in Dormagen, Germany. The company will invest about €150m in the facility, which will have a TDI production capacity of 300,000t a year.
Bayer MaterialScience will solely produce TDI from the Dormagen site. The TDI facility will replace the company's existing plants in Brunsbüttel and Dormagen. The approval process for the world-scale TDI plant will begin in the first half of 2010. The plant is expected to go on stream in 2014.
Bayer MaterialScience TDI plant background
Bayer MaterialScience planned the TDI plant in Dormagen Chempark in December 2008 and presented it for approval to the Cologne regional government.
Dormagen Chempark is a 570ha area, which has been serving the chemical industry since 1917.
The TDI plant will be built on the site of a coal-fired power plant, which will be demolished.
Chempark Dormagen was chosen for the TDI plant after a Europe-wide site selection process. The site has abundant availability of raw materials such as chlorine and TDI precursors. The company will build a new reformer for the production of carbon monoxide to facilitate TDI production. Chempark Dormagen also has the infrastructure to process hydrogen, the by product of carbon monoxide production.
Bayer MaterialScience is also planning to increase the raw materials production of its polyurethane rigid foams with expansion of the Brunsbüttel facility. The production of methylene di-para-phenylene isocyanate (MDI) will also be increased at the Brunsbüttel site from 160,000t to 400,000t a year.
Gas phase TDI production technology
Bayer MaterialScience has been producing TDI in Dormagen since 1964. The TDI plant at Chempark will use a new gas phase phosgenation technology developed by the company at the site. The technology was tested at a pilot plant in 2004 and met the safety standards.
The process is being implemented on a large-scale at a plant in Caojing, China, which is scheduled to go on stream in mid-2011. The patented gas phase phosgenation TDI production process is expected to save 60% of energy compared with traditional processes. It is also expected to be environmental friendly and reduce the solvent consumption by about 80%.
TDI plant process technology
Flexible polyurethane foams are produced with the reaction of a polyether polyol with TDI. TDI is produced in a sequence of steps from naphtha – a material obtained from crude oil. Aromatic compounds from naphtha are separated to obtain toluene, the primary hydrocarbon feedstock. Toluene is further nitrated using nitric acid and the reaction produces dinitrotoluene (DNT).
The hydrogenation of DNT produces toluenediamine (TDA), which is then converted to TDI using the phosgenation technology. The gas phase phosgenation process of Bayer MaterialScience includes heating TDA and phosgene at about 300°.
The gaseous chemicals produced are reacted and condensed to form liquid TDI. The final step involves the distillation of TDI to remove excess phosgene and the solvent. The distillation phase of the process is claimed to save about 40% of energy compared with traditional processes.
The traditional processes involve the reaction of TDI and phosgene in dilute solution forms in a solvent such as ortho-dichlorobenzene.
Isocyanate market growth
Bayer MaterialScience's investment in Dormagen is expected to strengthen the position of the Chempark site as a global TDI technology centre. With the TDI plant, the company aims to increase its isocyanate production in Europe.
TDI is an important intermediate in the production of flexible polyurethane foams. The foams are used for various modern daily products such as chairs and seating, cold foam mattresses and cushions of automobiles and office chair seats.
The product is also used for the protective packaging and cushioning of several electronic goods, and for leisure and sports applications. The company expects the demand for TDI to increase in the long term, thus expanding its position in the global market.
