VanLare Wastewater Treatment Facility - Incineration
While meeting all of today's environmental standards, incineration
provides an economical and efficient means of reducing the volume
of the end product of wastewater treatment. Initially constructed
in 1972, the air pollution control equipment currently used at
VanLare allows the facility to meet the stringent EPA 503 guidelines
without any modifications.
Three multiple hearth incinerators provide thermal destruction
of the cake product (the end product of dewatering). Burners
of several configurations are used; all have dual fuel capability,
with natural gas being the fuel of choice. All incinerators are
also equipped with afterburners for odor control, located in the
top hearth of the incinerator. These afterburners are always
operating at 1230-1300 degrees Farenheit, and consume about 60%
of the total fuel used for incineration.
Incinerator #3 has a 22 foot diameter and a six hearth unit.
Incinerators #4 and #5 have 22 foot diameters and eleven hearth
units. After the cake is combusted within the multiple-hearth
incinerator, a volume reduction of 75% is achieved, with sterile
ash being the ultimate product. The ash exits the incinerator,
passes through a crusher, and is mixed into a slurry. The ash
slurry is transported to two lagoons which are dredged out four
times a year, with the ash going to a landfill.