HOUSTON --A decline in the quality of US asphalt - due to more intense refining of crude oil by-products - could encourage the use of styrene-butadiene rubber (SBR) and other polymers in roofing and roads, industry experts said on Friday.
"Refineries don't run to make good asphalt. They run to make fuels," said Andrew Fox, director of design and development at SemMaterials, an asphalt producer and marketer based in Tulsa, Oklahoma.
Each short ton (st) of asphalt used in the US includes between 10 lb (4.5kg) and 50 lb of additives, while US demand for asphalt was steady at about 30m st/year, Fox said on the sidelines of an asphalt conference in Houston, sponsored by Argus Media.
As well as SBR, polymers and specialty chemicals used to modify asphalt include styrene butadiene styrene (SBS) and ethylene vinyl acetate (EVA), he said. Fox did not have any specific estimate of how much polymer demand in the asphalt sector might grow.
Modifying asphalt with polymers addresses issues of brittleness in cold weather and softness in higher temperatures. Those properties vary according to the type of crude used to produce the asphalt.
That leaves end users vulnerable to refiners' willingness to alter their choice of crude grades at short notice to maximise returns from higher-value products, such as gasoline and jet fuel, said Allen Smith of Asphalt & Sourcing Alliance, a consultancy based in New Jersey.
Polymers were particularly important in the roofing industry, which, unlike road construction, is not faced with government-set quality parameters for asphalt products.
"You can forgive the sins of asphalt by adding polymers," Smith said.
The trend toward lower-quality asphalt will continue because the US refining industry was meeting fuel demand growth by upgrading existing refineries to handle heavier - but relatively cheaper - grades of crude oil, including future output from Canadian oil sands projects.
There were 25 major capital expansion projects at North American refineries to be completed within three years, Smith said.
Those projects would see around 3m st of asphalt diverted into 15 new cokers instead of finding its way into the physical market, he said.
The US Gulf coker value of asphalt was currently around $525/st, compared with the price of asphalt at around $325/tonne.
Houston-based Kraton Polymers is the leading global supplier of polymers for asphalt applications. On 27 March it reported a gross profit of $21m (?3m) for the fourth quarter down by 43% from a year earlier.
Kraton blamed the fall on higher costs for monomers and other inputs, which offset a 2% rise in sales volumes for all of 2007.
"Refineries don't run to make good asphalt. They run to make fuels," said Andrew Fox, director of design and development at SemMaterials, an asphalt producer and marketer based in Tulsa, Oklahoma.
Each short ton (st) of asphalt used in the US includes between 10 lb (4.5kg) and 50 lb of additives, while US demand for asphalt was steady at about 30m st/year, Fox said on the sidelines of an asphalt conference in Houston, sponsored by Argus Media.
As well as SBR, polymers and specialty chemicals used to modify asphalt include styrene butadiene styrene (SBS) and ethylene vinyl acetate (EVA), he said. Fox did not have any specific estimate of how much polymer demand in the asphalt sector might grow.
Modifying asphalt with polymers addresses issues of brittleness in cold weather and softness in higher temperatures. Those properties vary according to the type of crude used to produce the asphalt.
That leaves end users vulnerable to refiners' willingness to alter their choice of crude grades at short notice to maximise returns from higher-value products, such as gasoline and jet fuel, said Allen Smith of Asphalt & Sourcing Alliance, a consultancy based in New Jersey.
Polymers were particularly important in the roofing industry, which, unlike road construction, is not faced with government-set quality parameters for asphalt products.
"You can forgive the sins of asphalt by adding polymers," Smith said.
The trend toward lower-quality asphalt will continue because the US refining industry was meeting fuel demand growth by upgrading existing refineries to handle heavier - but relatively cheaper - grades of crude oil, including future output from Canadian oil sands projects.
There were 25 major capital expansion projects at North American refineries to be completed within three years, Smith said.
Those projects would see around 3m st of asphalt diverted into 15 new cokers instead of finding its way into the physical market, he said.
The US Gulf coker value of asphalt was currently around $525/st, compared with the price of asphalt at around $325/tonne.
Houston-based Kraton Polymers is the leading global supplier of polymers for asphalt applications. On 27 March it reported a gross profit of $21m (?3m) for the fourth quarter down by 43% from a year earlier.
Kraton blamed the fall on higher costs for monomers and other inputs, which offset a 2% rise in sales volumes for all of 2007.
