World visitors trek to Brazil's ambitious oil shale project

In the midst of idyllic rolling hills and fertile farms, one of the world's most ambitious energy projects is taking shape near this isolated Brazilian hamlet.

Operated by the Brazilian oil company Petrobras, a prototype oil shale plant is processing gray shale rock into an oil that can be refined and used as fuel for automobiles.

A visit to the limited access facility requires an all-day excursion from the nearest major airport city, Curitiba, over a bumpy road that is passable only during the dry season. Still, visitors from all over the world make the trek to inspect the unique project.

* In May a World Bank group from Washington visited the plant in anticipation of a possible loan.

* The United States Department of Energy has sent representatives and commissioned a study to assess the development of oil shale in Brazil and its relevance to the US.

* And representatives of the Japanese Oil Company are currently visiting Brazil to negotiate an agreement to participate in the $2 billion project to build a commercial plant capable of producing 50,000 barrels a day of oil from shale.

The Brazilians expect to begin preliminary construction on the commercial facility sometime this year.

Although extraction of oil from shale rock has been going on for over 150 years, it is only recently that the technology has become commercially economic because of the staggering jump in the price of oil, despite the recent softening of the oil market. As a result, major oil companies in both the US and Brazil are making multibillion-dollar commitments to this new technology.

The potential of oil shale in the Western US and Colorado is believed to be enormous. At least three times the world's conventional oil reserves are tied up in rocks in a 16,000 square mile area in Colorado, Utah, and Wyoming.

In Brazil's Parana region alone, where the prototype plant is located, shale deposits are estimated to contain the equivalent of 560 million barrels of oil. In Brazil, Petrobras is planning for a commercial facility to start operating in 1985 to produce 50,000 barrels a day of shale oil. The current prototype -- which is producing 700 barrels a day -- s a "mini model" of the commercial plant , which will consists of 20 modules, each processing 2,500 barrels a day of oil equivalent.

The shale deposits in the Parana region are in two layers. The top layer has an oil proportion of about 6.4 percent; the lower layer has about a 9.1 percent oil content. Drag lines pile the superior layer over the bottom oil shale which has been broken up by an explosive device. The shattered shale is sent through a crusher where it is broken down into pieces ranging from six inches to eight inches. It then goes through a second crusher to be broken up into pieces ranging in size from one-quarter of an inch to 2 1/2 inches. Shale that is finer than one-quarter of an inch is generally discarded because it cannot be used in the "Petrosix" process which extracts the oil from the shale. The Petrosix process, developed exclusively by Brazil, is kept closely guarded by oil company officials.

The prototype plant is currently producing sulfur, synthetic gas, and light and heavy oil. The gas is used to fuel the plant, making it self-sufficient in energy. The sulfur can be sold to industrial users, according to Petrobras officials. Heavy oil, which is used by utilities in power generation, represents 70 percent of the oil output. Light o il, used by automobiles, comprises 30 percent.