Technology
Pyrament concrete strengthens Flexural strength, psi
faster than portland types Compressive strength, psi
800|
600
Strength for airport-and bridge traffic
Pyrament
400
200
Portland type I
ι , ι ,,
4000
3000
2000
1000
0
Pyrament^^^^M
' Ji^0^^^-:'' : |
'\'''-M' Portland type 111 |
m'• . > ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ o r t l a n d ¥'- ' ̂ ^^τ\*^ί^^^- type 1
4 6 8
Hours since setting
Source: Lone Star Industries
12 4 6 8 10
Hours since setting
12
He hints that the remainder contains pozzolan, a class of materials that reacts with the calcium hydroxide that is produced in portland cement hydration reactions.
"I'm curious, having worked in these areas, just what is really different about Pyrament/ ' says Roy. "We speculate it contains pozzolan, but how much? And what else? It would take a fair amount of trouble to find out what's in it, but it probably could be done."
By calling its new cement Pyrament, Lone Star is deliberately invoking the pyramids of Egypt. The company's promotional literature says that "Pyrament concrete offers the strength of the pyramids." However, the term Pyrament also calls up associations with French polymer chemist Joseph Davidovits, who for years has been claiming that the Egyptian pyramids were not built of blocks of quarried stone but are mineral polymers—man-made stone like concrete—cast on the spot.
Davidovits' theories have received a chilly reception in the archaeological community, but he has obtained patents on synthetic stone formulations he calls geopolymers. And indeed, Lone Star's Pyrament does have a connection to Davidovits' research. According to Margie Morris, Davidovits' Detroit-based associate who has collaborated on a book with him, Lone Star executives embarked on the road that led to Pyrament after reading about Davidovits in a 1983 article in Omni magazine.
"I am the primary inventor," says
Davidovits, who says he worked with Lone Star as an employee and consultant from 1983 to 1988. "I claim we have developed Pyrament together. The current [material] is a continuation of what I've done."
Lone Star, however, seems to want to distance itself from Davidovits. Sawyer says that Lonestar used Davidovits' work as a starting point for Pyrament. "Initially we bought patent rights from Davidovits, and the material was given to me for evaluation," he says. "From there, we proceeded to activate a standard blended cement system. The current Pyrament formulation contains nothing of what he had."
Whatever its origins, Pyrament does seem to offer advantages over conventional cement that may make it worth its higher cost. It remains to be seen, however, whether the conservative U.S. construction industry will accept it.
"Pyrament is a product that has some excellent properties and a lot of potential," says PCA's Kosmatka. "We'll have to wait and see just how far it goes."
Pamela Zurer
ICI to expand its biotechnology business In a drive to expand and diversify its operations, ICI Biological Products is concentrating its efforts on fermentation. The company is installing a mult ipurpose unit in Billingham, England, which together with associated harvesting facilities will cost up to $20 million. Completion is planned for the middle of next year.
The decision points to the changing profile of the chemical industry in general and of ICI in particular. "This investment is a major step in our strategy to build a new business in biotechnology," comments ICI Biological Products general manager John Russell. "The multipurpose unit will enable us to supply a number of new products, including a novel biodegradable plastic, enzymes, and forage [silage] preservation products."
Although annual sales figures for the biological products operations are not available, they admittedly are small in relation to ICI's overall sales of around $18 billion a year. On the other hand, this latest move is a further indication of the aim of Denys H. Henderson, ICI's chairman, to expand what he refers to as the effect chemicals side of the opera
tions, specialties that have high growth potential and that generate better profits.
The biodegradable plastic that Russell refers to, for instance, could become commercially significant in light of the growing concern over the environmental impact of plastic waste. He declines to specify the organism involved. But following harvesting, the biomass is put through a series of processing steps to produce a plasticlike material, polyhy-droxybutyrate.
ICI Biological Products emerged recently as a spinoff from ICI's former agricultural division. It will draw on the fermentation experience gained from production some years ago of single-cell protein as an animal feed supplement. Trade-named Pruteen, the product involved cultivation of Methylophilus methylotrophus bacterium in a methanol medium (C&EN, Oct. 11, 1976, page 25). The fermenter, which could produce up to 75,000 metric tons annually, was touted as the largest of its kind when it started up in 1980. The project was discontinued because Pruteen couldn't compete commercially with soybean animal feed.
Dermot O'Sullivan
38 February 13, 1989 C&EN
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