A Brief History of Eterra and the Flash Evaporator

In 1975 I shared an office with a cigar-smoker who eventually died of lung cancer. Second-hand smoke was not considered a problem back then. At least not by most people. I was at that time, however, working under contract to the Environmental Protection Agency, studying the cancer-causing chemicals produced by incomplete combustion, as in cigarettes, cigars, and in the oxygen-starved combustion of coal and solid waste.

One day, as a part of my job, I visited a new kind of solid-waste incinerator which Monsanto had designed and built for the city of Baltimore. My task was to decide whether to bid on doing an economic analysis of the incinerator's performance.

The special feature of the Monsanto incinerator was that it was designed to burn the solid waste incompletely, thereby producing lots of smoke, which has fuel value; i.e., the smoky "fuel gas" could be piped to and used to heat office buildings in Baltimore's downtown area. The process of incomplete combustion is called "pyrolysis," which translates roughly as "broken apart by fire."

The incinerator's design was clever, and at some point during the day I realized that tobacco could probably also be heated without combustion -- in other words, I realized that electrically heated pure air could be used to evaporate the taste and nicotine into an inhalable airstream without having to use the tobacco itself as the energy source to produce the hot gases that evaporate the taste and nicotine.

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