초록 ▼

An industrial waste management facility (IWMF) for disposing of spent potlining includes a co-current gas-fired rotary kiln for containing a molten pool of spent potlining throughout the entire length of the rotary kiln from the inlet to the outlet, an ash quencher and cooler for receiving molten re

An industrial waste management facility (IWMF) for disposing of spent potlining includes a co-current gas-fired rotary kiln for containing a molten pool of spent potlining throughout the entire length of the rotary kiln from the inlet to the outlet, an ash quencher and cooler for receiving molten residue from the discharge end of the rotary kiln, a secondary combustion chamber, and a down-draft transition chamber for channeling discharge gases from the rotary kiln to the secondary combustion chamber. Pneumatic injection slingers feed and distribute spent potlining into the inlet end of the rotary kiln. A discharge dam provides a predetermined average depth of molten bath material in the rotary kiln over its entire length. A blended ratio of comminuted materials injected through the pneumatic injection slinger feeder is adjusted and controlled in response to signals received from a radiative optical kiln bath temperature measurement system. The IWMF recovers fluorides from discharge gases exiting the secondary combustion chamber, recycles the fluorides to the molten bath or pool of the rotary kiln, and collects and withdraws glass frit residue from the ash quencher and cooler.

대표청구항 ▼

A process for treating spent potlining from the electrolytic smelting of aluminum, comprising: (a) heating spent potlining by admixing into a molten salt bath comprising sodium, aluminum, fluoride, calcium, and silicon salts in a rotary kiln vessel at a salt bath temperature in the range of about 11

A process for treating spent potlining from the electrolytic smelting of aluminum, comprising: (a) heating spent potlining by admixing into a molten salt bath comprising sodium, aluminum, fluoride, calcium, and silicon salts in a rotary kiln vessel at a salt bath temperature in the range of about 1100°C. to 1250°C. while maintaining, a pool of molten salt bath containing said spent potlining over the entire length of said rotary kiln vessel; (b) reducing the carbon content of said bath by admixing a solid oxygenating and gasifying compound into said pool of molten salt bath and spent potlining; (c) adding siliceous material to said bath potlining; and (d) cooling and discharging a portion of said bath to form a glassy residue suitable for land-fill.