BP Chemicals Ltd. is offering twice the polyethylene for not even half the price. But at least one major competitor is not impressed. The London petrochemical giant announced Jan. 17 it has developed a new technology that can be used - with a relatively low capital investment - to double the output of existing gas-phase reactors used to make PE.
While the announcement appears to mark a breakthrough in technology used to make PE, it was challenged by Union Carbide Corp. of Danbury, Conn., as being suspiciously similar to Union Carbide's patented condensing mode technology for PE in gas-phase, fluidized bed reactors.
Union Carbide and BP Chemicals have vied strenuously - on a worldwide basis - for dominance in gas-phase technology for the production of PE for many years. The companies provide competing types of gas-phase reactors to produce PE, and count licensing fees for PE technology as important portions of their corporate income.
However, Martin Howard, general manager of licensing for BP Chemicals, said in a telephone interview Jan. 25 that BP's new technology is unique.
Howard said the new technology can be retrofitted easily to existing gas-phase reactors, and can be used to double reactor output with a low investment.
The technology uses concepts BP developed for catalytic crackers used in the oil industry to reduce the heat generated in the polymerization process, he said. That heat has been a limiting factor in polymer production.
The new BP process uses an external hydrocarbon loop to remove surplus liquids and gases from the reactor. Those surplus liquids and gases are cooled and condensed outside the reactor, and mixed with additional ethylene comonomer and hydrogen.
Then, the gases are separated from the liquids and returned to the reactor as a normal feedstock, and the liquids are injected into the reactor. One of the primary differences between the new BP process and the Union Carbide process is the way the liquids are returned to the reactor, Howard said. It is the return of that liquid that uses the technology developed for the oil industry.
The liquids are sprayed into the reactor at a level above the grate that supports the fluidized bed, Howard said. That spraying technique distributes the liquid evenly and provides a more stable process than previous technologies, he said.
Also, he said the vaporization of the liquid provides the cooling effect that stabilizes the temperature in the reactor, and helps maintain a constant temperature - between 146§-326§F - from the bottom to the top of the reactor vessel.
The cooling aspects of the new technology and its ability to maintain a constant temperature within the reactor expand the production capacity, Howard said.
He said BP Chemicals has seen reactor productivity double in pilot operations of the technology, and the company is installing the process at its PE production facility in Grangemouth, Scotland.
BP is looking forward to licensing the new technology to the users of its gas-phase production technology for PE, Howard said. He would not discuss the costs of the technology.
Howard said BP published its patent application Dec. 8, more than three months after Union Carbide issued a legal writ alleging that BP was infringing on its patents for similar technology.
Howard said Union Carbide has not filed claims to elaborate the writ of infringement it filed in September, but has received extensions for such filings. Usually, such filings are required to be made within 28 days of the original filing, he said.
Union Carbide is using the legal action to defend several patents it holds on condensing mode technology that cover a process to cool reaction gases to low temperatures so that they form liquids that are reintroduced to fluidized bed reactors, a company spokesman said.
``We haven't examined their claims, but what we have heard smacks of the condensing mode technology that we invented several years ago,'' Lou Agnello, Union Carbide's spokesman said.
``We anticipated Union Carbide's reaction,'' said BP's Howard. ``We've spent a lot of effort to be confident that we would be able to use this technology and license it worldwide.''
