March/April 2012

A hundred years of fossil fuels research at CANMET

Part 2: the 1950s onwards

By David Reeve

Part 1 of this history of fossil fuels research at CANMET, formerly the Mines Branch, traced the development and impact of programs from the founding of the Branch in 1907 to the post-war period of the 50s.

Post-war prosperity to the 1970s

In a period of increasing prosperity after the war years, Mines Branch programs shifted to an emphasis on science. Completion of the TransCanada pipeline and dieselization of the railways resulted in a loss of large coal markets in the transportation and residential sectors, and the country’s energy dependence switched from mainly coal to natural gas and oil. Nevertheless, coal technology programs were continued, a decision that proved to be propitious after the energy crisis of the early 1970s.

A program on coal preparation had two objectives: to encourage eastern Canadian coal producers to install wash plants that would reduce the sulphur content of their coals in order to make them more competitive with high-quality imported coals, and to reduce the ash content of western Canadian friable coals. With respect to the second objective, a compound water cyclone, in which coal and mineral matter (ash) particles were separated according to specific gravity, was developed at the Western Regional Laboratory in Edmonton. This hydrocyclone was installed in coal wash plants in several countries, and in 1972 a unit was installed at DEVCO’s Lingan Mine to reduce the sulphur content of Cape Breton coal.

In 1958, a delegation of six western Canadian coal operators, a representative of the Dominion Coal Board, and a technical expert from the Mines Branch Fuels Division visited Japanese steel mills that were rebuilding after the war. Following carbonization tests in the Booth Street experimental coke oven that demonstrated the feasibility of using Canadian coals in blends with Japanese coals for the manufacture of blast-furnace coke, 100,000 tons of Canadian coking coals were shipped to Japan. A second technical mission was dispatched to Japan in 1960, to convince the Japanese steel companies of the quality of the Canadian coals. Many believe the success of this mission was the turning point in enabling western Canadian coal producers to gain a foothold in the Japanese market. This strong confidence in the carbonization work carried out at the Fuels Division led to the formation of the Canadian Carbonization Research Association (CCRA) in 1965, an industry-government cooperative venture with members from both coal-producing and consuming companies.

While coking coal companies were able to develop markets for their coal in Japan, producers of non-coking coals, such as Canmore Mines Ltd., which produced semi-anthracite, could not. A small-scale vertical shaft carbonizing unit was constructed on Booth Street to carbonize briquettes of Canmore coal, leading to the operation of an experimental two-ton per hour unit at the Canmore mine site. Finally, a 30,000-ton-per-year commercial unit was constructed with sale of the product to the phosphorus industry in the United States.

At the outset of this period, Fuels Division combustion work was directed at encouraging coal use in Canada by means of new domestic and commercial stoker grate-fired boiler designs that incorporated operating protocols for smokeless operation. However, the availability of cheap offshore oil rapidly replaced coal use and the testing of coal in domestic heating appliances was soon discontinued.

The Division also oversaw the development of pressurized pulverized fuel combustion that would help bring a coal-fired gas turbine for locomotive use to market. This was of particular interest to the coal producers and to the railroads that wished to stem the advance of oil in the transportation field. In 1950, an agreement was reached with McGill University to construct and operate a demonstration plant using a 500 hp aero engine. The unit was commissioned in 1953 but interest from the railway companies waned when it became evident that continued dieselization of the railways would take place. As a result, the project was shelved in 1958.

Studies were conducted between 1957 and 1962 to improve the combustion of Cape Breton coal in stokers installed in the heating plants of government buildings. However, the view in the Division was that the future of thermal coals in Canada lay in their increased use for power generation and for large industrial applications. The focus of the development work then shifted to designing and using pilot-scale furnaces that closely simulated power station conditions. A combustion research unit was designed and built to measure combustion reactions and the aerodynamics of burner design. The unit was first used for assessment of the combustion properties of eastern Canadian high-sulphur coals and Saskatchewan lignites. Because of increasing concern over air pollution, plume-rise equations were developed to predict how stack gases would disperse from tall chimneys. Field particulate settling studies allowed relationships between concentrations of sulphur dioxide and distance from the stack to be established.

With respect to oil sands technology development during this period, the division participated in an evaluation of the technical and economic feasibility of commercial oil production from bitumen in Alberta. However, industry interest remained low because of the rapid development of conventional oil production. With regard to bitumen upgrading, the oil industry favoured the cheaper coking process but the Fuels Division considered that hydrocracking, which offered a higher product yield than coking, would ultimately be needed and that reactors operating at very high pressures would be required.

Immediately after World War II, a visit was made to plants in Germany that used the Bergius process, a method of direct conversion of coal to liquid by hydrogenation. These facilities had been operated at extremely high pressures to manufacture fuel for the war effort. Using technical information from this visit, a pilot-scale hydrogenation reactor was designed and commissioned on Booth Street in 1955.

Cobalt molybdate fixed-bed catalysts on an alumina base were initially used, but problems arose because of catalyst deactivation. These difficulties led to a new program initiative on the properties of catalysts and their performance in refinery processes. In addition, because the chemical structure of the complex hydrogen-deficient bitumen hydrocarbon molecule was not well known, a fundamental research program on bituminous substances was launched, particularly aimed at the asphaltene component with the highest molecular weight and the lowest content of hydrogen.

The Booth Street high-pressure pilot plant was dismantled and reassembled at the new Bells Corners Laboratory in 1969-1970. It was subsequently dismantled again and shipped to Alberta for use by the provincial government, never to be reassembled.

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