Stokes, Rufus
1922-1986 · Contribution: 1968-1970
Invented the “Clean Air Machine,” a self-taught engineer's air-purification device that reduced gas and ash emissions from industrial furnace and power-plant smokestacks, patented in 1968 and improved in 1970
Portraits are AI-generated interpretations, not photographs.
Impact on the world
After witnessing the health toll of Chicago's industrial pollution while working as an orderly in a Veterans Hospital tuberculosis ward in the late 1940s, Stokes took a job as a machinist at Chicago incinerator manufacturer Brule, Inc., where he learned the combustion process and contributed uncredited work to new incinerator designs; frustrated at the lack of recognition, he spent the next 15 years developing his own pollution-control device largely with spare and borrowed parts and his personal savings, receiving U.S. Patent No. 3,378,241 for an “Exhaust Purifier” in 1968 and an improved version, Patent No. 3,520,113, in 1970. Built around what Stokes called “the three Ts” — temperature, time, and turbulence — his device worked efficiently at both large industrial and small residential scale, unlike bulkier contemporary pollution-control technologies such as electrostatic precipitators and wet scrubbers, though skepticism from major polluting companies limited its commercial adoption during his lifetime. Stokes earned a doctor of science degree from Heed University in 1982 in recognition of his engineering achievements, was later posthumously honored on the U.S. Department of Energy's list of “Energy Pioneers,” and died of mesothelioma in 1986 shortly after being brought on as a consultant to a Los Angeles wastewater treatment facility.
Life & background
Born September 3, 1922, in Phenix City, Alabama, Stokes enlisted in the U.S. Army's Quartermaster Corps before finishing high school and trained as an automobile mechanic during his military service. He worked as a hospital orderly and later a machinist at a Chicago incinerator company before spending 15 self-funded years developing his air-purification invention, founding the Air Pollution Control Corporation of America, and receiving his key patents in 1968 and 1970; he died of mesothelioma on June 1, 1986, at age 63.
Sources
- African American Registry; U.S. Energy Information Administration (Dept. of Energy, "Energy Pioneers"); U.S. Patent 3,520,113,
More in Industrial & Mechanical
Boyd, Henry
1802-1886
Invented the Boyd bedstead, a reinforced wooden bed frame design; founded a bedstead factory
Brooks, Charles
1865-unknown
Street sweeper truck design; paper punch
Coffey, Cornelius Robinson
1903-1994
Became the first African American certified aircraft mechanic in the United States in 1932 and designed a patented carburetor heating system that prevented icing, allowing aircraft to fly safely in cold and wet weather, a design principle still used in aviation today
Crosthwait, David Jr.
1892-1976
Heating, ventilation, and air conditioning (HVAC) system design