US 4,400,154 A · Refuse burning apparatus

Abstract

A process is provided for burning refuse containing polyvinyl chloride without the consequent production of phosgene. The refuse is carbonized in a rotary furnace at temperatures below 1200 degrees F., especially 700 degrees F., in an oxygen deficient atmosphere. A burnable gas containing the carbonized refuse is drawn from the furnace by an air jet wherein same is mixed with oxygen and selectively combusted. Uncarbonized refuse is collected and withdrawn after exiting the furnace. An apparatus is provided for combustion of the refuse in the nonphosgene generating process and includes the rotary furnace. Special seals are provided for the furnace to prevent excess oxygen from entering thereinto. In particular, the seals are utilized between the rotary ends of the furnace and stationary head associated with each end respectively. Each seal includes an upper and lower flap of fire resistant material secured to an end of the furnace and a companion flap of like material is secured to an associated end of the stationary head such that the intermediate flap sealably slides between the upper and lower flaps during rotation of the furnace thereby substantially sealing between the furnace and the stationary head.

Claims10

Dependent claims

In a rotary furnace having a middle section rotating with respect to a head with space sufficient to allow flow of gas therebetween, the improvement comprising a sealing mechanism for the space between said middle section and said head including:

(a) a flexible upper fire resistant and generally flat strap and a lower fire resistant and generally flat strap encircling a first of said middle section or said head;
said upper and lower strap each being in overlapping relationship to one another and each being securely attached to said first of said middle section or said head;
and
(b) an intermediate flexible fire resistant and generally flat strap secured to and circumferentially encircling a second and opposite one of said middle section or said head;
said intermediate strap extending between said upper and said lower straps so as to normally engage therewith in a sealing relationship;
said intermediate strap being secured to said second one of said middle section or said head near a first circumferential edge thereof and having a second and opposite edge generally supported by the first of said middle section or said head, such that said intermediate strap seals over the space between said middle section and head during normal operation of said furnace but is free to rotate outwardly about said first edge to allow gas to escape from said furnace when a state of overpressure occurs therein;
(c) whereby oxygen is substantially restricted from passing between said middle section and said head and overpressure is relieved from said furnace.

4 more elements

A sealing mechanism for use in a rotary furnace having a first section and a second section rotatable relative to said first section and having a gap therebetween;

said sealing mechanism for restricting the flow of oxygen into said furnace between said first and second sections and for alternatively relieving excess pressure from within said furnace;
said sealing mechanism comprising:
(a) a plurality of straps including;
(1) first and second circumferential straps each attached along a first circumferential side portion thereof to an external cylindrical end of said first section and having a second circumferential side portion thereof being flexible relative to said first section and being supported on an exterior surface of said second section;
said first and second straps having intermediate portions in normal covering relation to said gap when said furnace is in a normal operating mode;
(2) a third circumferential strap attached along a first circumferential side portion thereof to a cylindrical end of said second section and having a second circumferential side portion being flexible relative to said second section and being supported on an exterior surface of said first section;
said second portion of each of said straps overlapping in a slidable manner relative to one another with said third strap interposed between said first and second straps;
said first and second straps sealably engaging said third strap;
and
(b) attachment means for attaching said first and second straps to said first section and said third strap to said second section;
(c) whereby oxygen for combustion within said furnace is substantially restricted from passing between said first and second section when said furnace has a vacuum state therein thereby allowing control of said furnace temperature and said straps are flexible outward by rotation about said first side portion thereof to relieve excess gas from said furnace during a state wherein the pressure within said furnace is substantially greater than atmospheric pressure.

8 more elements

Dependencies are inferred from the claim text.

Refuse burning apparatus

Life of this patent

Refuse burning apparatus

Life of this patent

Abstract

Claims10