As a result of a spill dating back to the 1970s, Togiak Fisheries was faced with 70,000 tons of diesel- and gasoline-contaminated soil on the shores of Togiak Bay, Alaska.
The remote fish-processing facility wanted to sell, but the plant was stuck with a $12 million price tag to clean up the site. The cost was overwhelming, as were the challenges that go into cleaning a five-acre site in a remote area of Alaska. Located in a region without roadways, the fishery would have to ship in all supplies and equipment by barge or plane.
Then the company found Sisters, Ore.-based Brady Environmental and its evaporative desorption thermal soil treatment system, which use hot air instead of an open flame (the traditional design). To produce that hot air, the Brady system uses hot-air tools from Leister Process Technologies, Kaegiswil, Switzerland. Brady Environmental learned about Leister’s hot air tools from Assembly Supplies Co., Escondido, Calif., a distributor of Leister Process Technologies hot-air tools, such as heaters, blowers and controllers, among others.
“After meeting with Dennis Van Grol [owner of Assembly Supplies Co.] and seeing other applications where the Leister tool was used, I felt very comfortable with it,” said geologist Patrick Brady, president and owner of Brady Environmental Inc. “I wanted to make sure it could be operated continuously because we turn on the oven for five months and never turn it off.”
Leister LE 40,000 heaters, which have 39 kW, pump hot air into the soil remediation ovens. Each heater is supplied with one Airpack blower, and the hot-air tools regulate the heat. By monitoring the system to ensure the temperature remains near 1,000°F (538°C), Brady can ensure that the air never reaches the oxidation temperature of 1,300°F (704°C), which produces emissions.
The soil oven is a modular design in an airflow system. Vapors are extracted and the contaminants they contain are destroyed before being released into the air.
Brady Environmental was able to complete Togiak’s project for $4 million rather than the original $12 million cost using its remediation ovens.