Modular plasma ARC waste vitrification system

Abstract

An improved plasma arc waste processing system has a crucible formed in a horizontally elongated shape with a low-ceiling-height plenum space above a melt pool and a waste input feed arranged sideways into the crucible. The plenum space conducts the off-gases through a channel into a horizontally adjacent, thermal resonant chamber. The combined volume of the plenum space and thermal resonant chamber provides a high ratio of plenum volume to surface area of melt pool for efficient pyrolization of waste at high throughput rates. The crucible and other system components can be arranged in standard sized cargo containers, to be modularly transported and assembled in populated areas or transported to and from remote areas, such as in medical crisis zones, military deployments, and war zones. As a further improvement, a water injector is used to inject water into the plasma field to remove excess carbon and form useful gas byrpoducts.

1 . An improved plasma arc waste processing system comprising: 
 (a) a crucible formed as a horizontally flat, enclosed container with a bottom wall and side walls for containing a melt pool in the crucible, and a ceiling wall connected to the side walls and defining a plenum space above the top level of the melt pool for containing a plasma of pyrolized gases generated from waste material fed onto the melt pool,    (b) a waste input feed communicating into the crucible through the side walls at one side position of the crucible with a feed opening positioned above a top level of the melt pool, and    (c) one or more plasma arc electrodes mounted through the ceiling wall with ends thereof positioned above the top level of the melt pool for generating a high-temperature ionization plasma from pyrolized waste material fed onto the melt pool,    (d) wherein the ceiling wall is dimensioned to form said plenum space with a relatively low ceiling height above the top level of the melt pool, and said plenum space communicates via a channel formed through the side walls into a thermal resonant chamber arranged at another side position of the crucible,    (e) said thermal resonant chamber providing an additional plenum volume along with said low-ceiling-height plenum space for allowing complete pyrolization of the waste material into elemental constituents.    
   
   
       2 . An improved plasma arc waste processing system according to  claim 1 , wherein the waste input feed is fed from a bulk extruder through the side walls of the crucible.  
   
   
       3 . An improved plasma arc waste processing system according to  claim 1 , wherein the joule-heating electrodes are mounted through the side walls at spaced intervals around the circumference thereof and project into the molten pool for maintaining melt temperatures in the pool.  
   
   
       4 . An improved plasma arc waste processing system according to  claim 1 , wherein off-gases generated in the plenum space are led through a channel in the side wall into the horizontally adjacent thermal resonant chamber.  
   
   
       5 . An improved plasma arc waste processing system according to  claim 1 , further comprising an injector for injecting water or fluid containing water into the plasma field to remove excess carbon by chemically combining to form hydrogen gas and carbon monoxide, thereby reducing carbon incandescence of the plasma arc electrodes.  
   
   
       6 . A transportable plasma arc waste processing system comprising: 
 (a) a crucible formed as a horizontally flat, enclosed container with a bottom wall and side walls for containing a melt pool in the crucible, and a ceiling wall connected to the side walls and defining a plenum space above the top level of the melt pool for containing a plasma of pyrolized gases generated from waste material fed onto the melt pool,    (b) a waste input feed communicating into the crucible through the side walls at one side position of the crucible with a feed opening positioned above a top level of the melt pool,    (c) wherein the crucible is dimensioned to form said plenum space with a relatively low ceiling height above the top level of the melt pool, and said plenum space communicates via a channel formed through the side walls into a thermal resonant chamber arranged horizontally adjacent the crucible,    (d) wherein said crucible and thermal resonant chamber are dimensioned to fit in a container of a standard cargo container size, and    (e) wherein other system components for the system are arranged to fit in containers of the same standard cargo container size as the crucible container, so that the crucible and its other system components can be readily transported in modular fashion in the containers of standard cargo container size.    
   
   
       7 . A transportable plasma arc waste processing system according to  claim 6 , wherein the crucible and other system components are arranged to be contained in standard 20-foot or 40-foot length cargo containers.  
   
   
       8 . A transportable plasma arc waste processing system according to  claim 6 , wherein the crucible and thermal resonant chamber are arranged in horizontally adjacent halves of the container.  
   
   
       9 . A transportable plasma arc waste processing system according to  claim 8 , wherein the container halves for the crucible and thermal resonant chamber are formed as separate half compartments that are assembled by sliding them together or apart on rails.  
   
   
       10 . A transportable plasma arc waste processing system according to  claim 6 , wherein a gas scrubber unit is arranged in another container of the standard cargo container size.  
   
   
       11 . A transportable plasma arc waste processing system according to  claim 10 , wherein the thermal resonant chamber has ducts for oxygen purging with ambient air and a quench conduit for ducting the off-gases to the scrubber unit in the first-mentioned container.  
   
   
       12 . A transportable plasma arc waste processing system according to  claim 10 , wherein the gas scrubber unit is arranged with a gas-fired auxiliary power generator in its container.  
   
   
       13 . A transportable plasma arc waste processing system according to  claim 6 , wherein a control room and an electrical equipment room are arranged together in another container of the standard cargo container size.  
   
   
       14 . A transportable plasma arc waste processing system according to  claim 6 , wherein a bulk extruder is arranged to feed waste material into the crucible through a port from outside a free end of the container for the crucible.  
   
   
       15 . A transportable plasma arc waste processing system according to  claim 6 , wherein a drain from the crucible is arranged to drain molten waste material from the crucible to a vitrification pen outside the container for the crucible.  
   
   
       16 . A transportable plasma arc waste processing system according to  claim 6 , wherein the crucible and thermal resonant chamber are arranged in horizontally adjacent halves of a standard sized 20-ft×8-ft×8-ft container.  
   
   
       17 . A transportable plasma arc waste processing system according to  claim 16 , wherein the crucible plenum space plus the thermal resonant chamber as additional plenum space take up about 75% and the crucible takes up about 25% of the inner volume of the container.  
   
   
       18 . A transportable plasma arc waste processing system according to  claim 16 , wherein the ratio of total plenum volume to surface area of the melt pool is in the range of about 20:1.  
   
   
       19 . An improved plasma arc waste processing system comprising: 
 (a) a crucible formed with a bottom wall and side walls for containing a melt pool in the crucible, and a ceiling wall connected to the side walls and defining a plenum space above the top level of the melt pool for containing a plasma of pyrolized gases generated from waste material fed onto the melt pool,    (b) one or more plasma arc electrodes mounted through the ceiling wall with ends thereof positioned above the top level of the melt pool for generating a high-temperature ionization plasma field from pyrolized waste material fed onto the melt pool, and    (c) an injector for injecting water or fluid containing water into the plasma field to remove excess carbon by chemically combining to form hydrogen gas and carbon monoxide, thereby reducing carbon incandescence of the plasma arc electrodes.    
   
   
       20 . An improved plasma arc waste processing system according to  claim 19 , wherein the injector injects water in controlled amounts and at sufficiently high pressures to traverse (before evaporation) into the plasma field so that it can combine therein with the carbon.