Integrated process of pyrolysis and gasification of waste and the derivatives thereof and apparatus for the implementation thereof

Abstract

Process and apparatus that integrate continuously the processes of pyrolysis in a rotary drum at average temperatures of 300 to 500° C. and gasification in a moving-grate gasifier at average temperatures of 500 to 800° C. to produce a mixture of gases originating from the processes of pyrolysis and gasification of waste and the derivatives thereof. The mixture of gases called “waste-derived combustible gases” is continuously passed through a Venturi system or an exhaust system and can be directed to a system for combustion or treatment and separation of the combustible fractions for subsequent energy recovery. Waste in the form of powder, fines, slurries, pastes or liquids can be thermally treated individually or in blends with other waste such as municipal solid waste, commercial waste or industrial waste, with additional energy recovery.

1 . Integrated pyrolysis and gasification process of waste and its derivatives comprising:
 step 1: feed the dosing feeder process ( 1 . 1 ) with waste and/or its derivatives;   step 2: dose the waste and its derivatives to be inserted into the rotary kiln set ( 1 . 2 );   step 3: by action of gases from the exothermic reactions of the gasifier set ( 1 . 3 ) at a temperature of around 650° C. carry out the endothermic processes of pyrolysis of waste and its derivatives in the rotary kiln set ( 1 . 2 );   step 4: direct materials that were not pyrolyzed under the conditions imposed in the rotary kiln ( 1 . 2 ) to the gasifier ( 1 . 3 ) by rotating the kiln ( 1 . 2 . 1 );   step 5: move the material in process in the gasifier ( 1 . 3 ) by the advancing and retreating action of the moving grate sets ( 1 . 3 . 1 . 2 ), so that they are subjected to the partial oxidation reaction with atmospheric air, used as a gasifying agent, blown by the air blower ( 1 . 3 . 9 ) in an upward flow that passes through the holes ( 1 . 3 . 1 . 1 . 2 ) of the grates ( 1 . 3 . 1 . 1 ) and ( 1 . 3 . 1 . 2 ) to carry out the sub stoichiometric gasification combustion reactions, undergoing control of the predominantly sub stoichiometric reactions, pressure ( 1 . 5 . 1 ), temperature ( 1 . 5 . 2 ), and oxygen content ( 1 . 5 . 3 ) sensors are used;   step 6: concomitant with step 5, the non-gasified materials in the gasification chamber ( 1 . 3 ) will be pushed through the moving grates ( 1 . 3 . 1 . 2 ) of the grate sections ( 1 . 3 . 1 ) to the ash extractor ( 1 . 3 . 8 ), as well as the fine materials that pass through the holes ( 1 . 3 . 1 . 1 . 2 ) in the grates go through the valves ( 1 . 3 . 5 ), through the screw conveyor ( 1 . 3 . 6 ), joining the rest of the ash in the conveyor ( 1 . 3 . 8 ), passing through the water or mechanical seal ( 1 . 3 . 7 ) to the outside of the gasifier ( 1 . 3 ) avoiding false air entering the gasifier ( 1 . 3 );   step 7: the gases produced in the gasifier ( 1 . 3 ) by the gasification reactions from the sub stoichiometric oxidation reaction of waste and its derivatives, will be drawn through the gas removal duct ( 1 . 1 . 5 . 4 ), passing through the interior of the rotary kiln ( 1 . 2 . 1 ), collaborating with the reaction in step 3 above;   step 8: the gases produced in the rotary kiln set ( 1 . 2 ) by pyrolytic reactions from the decomposition of waste and their derivatives, together with the gases derived from the gasification processes carried out in the gasifier ( 1 . 3 ) are sucked into the waste removal duct gases ( 1 . 1 . 5 . 4 );   step 9: flow of the gas removal duct ( 1 . 1 . 5 . 4 ), which is caused by the system composed of the air blower ( 1 . 4 . 1 ) and Venturi ( 1 . 4 . 3 ), generating a Venturi effect pulling the gases;   step 10: direct the gases drawn by the Venturi effect ( 1 . 4 . 3 ) to the entrance of the combustion chamber ( 1 . 4 . 8 . 1 ) tangentially to the chamber ( 1 . 4 . 8 );   step 11: concomitantly with step 10, inflate air flow, through a blower ( 1 . 4 . 6 ) and valve control ( 1 . 4 . 7 ), in the same rotational direction of the combustible gases derived from waste that enter tangentially into the combustion chamber ( 1 . 4 . 8 ) offering a minimum retention time of 1.5 seconds for gases inside the chamber at temperatures between 1,000° C. and 1,400° C.;   step 12: use the thermal energy generated at the output ( 1 . 4 . 9 ).   
     
     
         2 . Equipment integrated for pyrolysis and gasification of waste and its derivatives comprising:
 a set for feeding and dosing material and removing gases ( 1 . 1 )   a rotary pyrolysis set ( 1 . 2 )   a gasification set ( 1 . 3 ) and   a combustion set of the gases generated ( 1 . 4 ).   
     
     
         3 . Material feeder and doser and gas removal set ( 1 . 1 ), comprising:
 a) feeder ( 1 . 1 . 1 );   b) upper hopper ( 1 . 1 . 2 );   c) valve ( 1 . 1 . 3 ) to control the material input volume;   d) lower hopper ( 1 . 1 . 4 );   e) pyrolysis rotary kiln feeder ( 1 . 1 . 5 ) comprising:
 body ( 1 . 1 . 5 . 1 ), with hopper ( 1 . 1 . 5 . 1 . 1 ) 
 emergency valve ( 1 . 1 . 5 . 2 ); 
 safety chimney ( 1 . 1 . 5 . 3 ); 
 combustible gas outlet duct ( 1 . 1 . 5 . 4 ); 
 emergency valve ( 1 . 1 . 5 . 5 ); and 
 feeder/kiln seal ( 1 . 1 . 5 . 6 ). 
   
     
     
         4 . Rotary pyrolysis kiln set ( 1 . 2 ), according to  claim 2 , characterized by comprising:
 a) rotary kiln ( 1 . 2 . 1 ) containing:
 a body ( 1 . 2 . 1 . 1 ); 
 tracks ( 1 . 2 . 1 . 2 ); 
   b) gear motor ( 1 . 2 . 2 ) to drive the kiln rotation;   c) set of sensors ( 1 . 5 ) comprising:
 pressure transmitter ( 1 . 5 . 1 ); 
 temperature transmitter ( 1 . 5 . 2 ); and 
 O 2  analyzer and transmitter ( 1 . 5 . 3 ). 
   
     
     
         5 . Gasification set ( 1 . 3 ) according to  claim 2 , further comprising:
 a) sections containing:
 fixed grates ( 1 . 3 . 1 . 1 ) with:
 i) ramp ( 1 . 3 . 1 . 1 . 1 ); 
 ii) horizontal holes ( 1 . 3 . 1 . 1 . 2 ), and; 
 iii) sliding-fitting lower flap ( 1 . 3 . 1 . 1 . 3 ), and; 
 iv) sliding-fitting top flap ( 1 . 3 . 1 . 1 . 4 ); 
 
 moving grates ( 1 . 3 . 1 . 2 ) with:
 i) ramp; 
 ii) horizontal holes, and; 
 iii) sliding-fitting lower flap, and; 
 iv) sliding-fitting top flap; 
 
   b) hydraulic activation of the moving grates of the moving grates ( 1 . 3 . 1 . 2 ) of each section ( 1 . 3 . 1 );   c) hydraulic power plant with pump and reservoir ( 1 . 3 . 3 );   d) ash collectors ( 1 . 3 . 4 );   e) valves for ash collection ( 1 . 3 . 5 );   f) ash screw conveyor ( 1 . 3 . 6 );   g) water seal ( 1 . 3 . 7 );   h) Redler type conveyor ( 1 . 3 . 8 );   i) blower ( 1 . 3 . 9 );   j) blown air damper valves ( 1 . 3 . 10 );   k) gasifier/rotary kiln seal ( 1 . 3 . 11 )   l) level sensor/switch ( 1 . 3 . 12 );   m) sensor sets ( 1 . 5 ) on each section ( 1 . 3 . 1 ) comprising:   n) pressure transmitters ( 1 . 5 . 1 );   o) temperature transmitters ( 1 . 5 . 2 );   p) O 2  analyzers and transmitters ( 1 . 5 . 3 );   q) pressure transmitters ( 1 . 5 . 1 ) under each set of grates ( 1 . 3 . 1 ).   
     
     
         6 . Generated gas combustion set ( 1 . 4 ), according to  claim 2 , characterized by comprising:
 a) extraction fan ( 1 . 4 . 1 );   b) Venturi ( 1 . 4 . 3 );   c) recovery gas supply line ( 1 . 4 . 4 );   d) pilot burner for startup ( 1 . 4 . 5 );   e) burner fan ( 1 . 4 . 6 );   f) damper valve ( 1 . 4 . 7 );   g) combustion chamber ( 1 . 4 . 8 ) comprising tangential inlet of produced gases ( 1 . 4 . 8 . 1 );   h) hot gas outlet ( 1 . 4 . 9 );   i) natural gas or LPG input line for startup ( 1 . 4 . 10 );   j) set of sensors ( 1 . 5 ) comprising:
 pressure transmitter ( 1 . 5 . 1 ); 
 temperature transmitter ( 1 . 5 . 2 ); 
 O 2  analyzer and transmitter ( 1 . 5 . 3 ). 
   
     
     
         7 . Integrated process for pyrolysis and gasification of waste and its derivatives, according to  claim 1 , characterized by presenting the first variant of the process comprising the following steps:
 step 1: feed the dosing feeder process ( 1 . 1 ) with waste and/or its derivatives;   step 2: dose the waste and its derivatives to be inserted into the rotary kiln set ( 1 . 2 );   step 3: by action of gases from the exothermic reactions of the gasifier set ( 1 . 3 ) at a temperature of around 650° C. carry out the endothermic processes of pyrolysis of waste and its derivatives in the rotary kiln set ( 1 . 2 );   step 4: direct materials that were not pyrolyzed under the conditions imposed in the rotary kiln ( 1 . 2 ) to the gasifier ( 1 . 3 ) by rotating the kiln ( 1 . 2 . 1 );   step 5: move the material in process in the gasifier ( 1 . 3 ) by the advancing and retreating action of the moving grate sets ( 1 . 3 . 1 . 2 ), so that they are subjected to the partial oxidation reaction with atmospheric air, used as a gasifying agent, blown by the air blower ( 1 . 3 . 9 ) in an upward flow that passes through the holes in the grates ( 1 . 3 . 1 . 1 ) and ( 1 . 3 . 1 . 2 ) to carry out the sub stoichiometric combustion reactions of gasification, undergoing control of the predominantly sub stoichiometric reactions, pressure sensors are used ( 1 . 5 . 1 ), temperature ( 1 . 5 . 2 ), and oxygen content ( 1 . 5 . 3 );   step 6: concomitant with step 5, the non-gasified materials in the gasification chamber ( 1 . 3 ) will be pushed through the moving grates ( 1 . 3 . 1 . 2 ) of the grate sections ( 1 . 3 . 1 ) to the ash extractor ( 1 . 3 . 8 ), as well as the fine materials passing through the holes in the grates go through the valves ( 1 . 3 . 5 ), through the screw conveyor ( 1 . 3 . 6 ), joining the rest of the ash in the conveyor ( 1 . 3 . 8 ), passing through the water or mechanical seal ( 1 . 3 . 7 ) go outside the gasifier ( 1 . 3 ) avoiding false air entering the gasifier ( 1 . 3 );   step 7: the gases produced in the gasifier ( 1 . 3 ) by the gasification reactions from the sub stoichiometric oxidation reaction of waste and its derivatives, will be drawn through the gas removal duct ( 1 . 1 . 5 . 4 ), passing through the interior of the rotary kiln ( 1 . 2 . 1 ), collaborating with the reaction in step 3 above;   step 8: the gases produced in the rotary kiln set ( 1 . 2 ) by pyrolytic reactions from the decomposition of waste and their derivatives, together with the gases derived from the gasification processes carried out in the gasifier ( 1 . 3 ) are sucked into the waste removal duct gases ( 1 . 1 . 5 . 4 );   step 9: flow of the gas removal duct ( 1 . 1 . 5 . 4 ) which is caused by the exhaust fan ( 1 . 4 . 11 ) pulling the gases;   step 10: direct the gases drawn by the exhaust fan ( 1 . 4 . 11 ) to the combustion chamber entrance ( 1 . 4 . 8 . 1 ) tangentially to the chamber ( 1 . 4 . 8 );   step 11: concomitantly with step 10, blow the only air flow into the combustion chamber ( 1 . 4 ) through a blower ( 1 . 4 . 6 ) and valve control ( 1 . 4 . 7 ), in the same direction as the rotation of the combustible gases derived from waste that enter tangentially into the combustion chamber ( 1 . 4 . 8 );   step 12: make use of the thermal energy generated.   
     
     
         8 . Equipment integrated for pyrolysis and gasification of waste and its derivatives, according to  claim 2 , characterized by the fact that it is presented as the first variant of the equipment comprising replacing the system with Venturi ( 1 . 4 . 3 ) and blower ( 1 . 4 . 1 ) by an exhaust fan ( 1 . 4 . 11 ) of hot gases with speed and flow control by frequency inverters, with combustion air being injected exclusively at the inlet of the combustion chamber, through the blower ( 1 . 4 . 6 ). 
     
     
         9 . Integrated process for pyrolysis and gasification of waste and its derivatives, according to  claim 1 , characterized by presenting the second variant of the process comprising:
 step 1: feed the dosing feeder process ( 1 . 1 ) with waste and/or its derivatives;   step 2: dose the waste and its derivatives to be inserted into the rotary kiln set ( 1 . 2 );   step 3: by action of gases from the exothermic reactions of the gasifier set ( 1 . 3 ) at a temperature of around 650° C. carry out the endothermic processes of pyrolysis of waste and its derivatives in the rotary kiln set ( 1 . 2 );   step 4: direct materials that were not pyrolyzed under the conditions imposed in the rotary kiln ( 1 . 2 ) to the gasifier ( 1 . 3 ) by rotating the kiln ( 1 . 2 . 1 );   step 5: move the material in process in the gasifier ( 1 . 3 ) by the advancing and retreating action of the moving grate sets ( 1 . 3 . 1 . 2 ), so that they are subjected to the partial oxidation reaction with atmospheric air, used as a gasifying agent, blown by the air blower ( 1 . 3 . 9 ) in an upward flow that passes through the holes in the grates ( 1 . 3 . 1 . 1 ) and ( 1 . 3 . 1 . 2 ) to carry out the sub stoichiometric combustion reactions of gasification, undergoing control of the predominantly sub stoichiometric reactions, pressure sensors are used ( 1 . 5 . 1 ), temperature ( 1 . 5 . 2 ), and oxygen content ( 1 . 5 . 3 );   step 6: concomitant with step 5, the non-gasified materials in the gasification chamber ( 1 . 3 ) will be pushed through the moving grates ( 1 . 3 . 1 . 2 ) of the grate sections ( 1 . 3 . 1 ) to the ash extractor ( 1 . 3 . 8 ), as well as the fine materials passing through the holes in the grates go through the valves ( 1 . 3 . 5 ), through the screw conveyor ( 1 . 3 . 6 ), joining the rest of the ash in the conveyor ( 1 . 3 . 8 ), passing through the water or mechanical seal ( 1 . 3 . 7 ) go outside the gasifier ( 1 . 3 ) avoiding false air entering the gasifier ( 1 . 3 );   step 7: the gases produced in the gasifier ( 1 . 3 ) by the gasification reactions from the sub stoichiometric oxidation reaction of waste and its derivatives, will be drawn through the gas removal duct ( 1 . 1 . 5 . 4 ), passing through the interior of the rotary kiln ( 1 . 2 . 1 ), collaborating with the reaction in step 3 above;   step 8: the gases produced in the rotary kiln set ( 1 . 2 ) by pyrolytic reactions from the decomposition of waste and their derivatives, together with the gases derived from the gasification processes carried out in the gasifier ( 1 . 3 ) are sucked into the waste removal duct gases ( 1 . 1 . 5 . 4 );   step 9: flow of the gas removal duct ( 1 . 1 . 5 . 4 ) which is caused by the exhaust fan ( 1 . 4 . 11 ) pulling the gases;   step 10: direct the gases drawn by the exhaust fan ( 1 . 4 . 11 ) to the treatment and separation system for combustible fractions sent to various energy use processes.   
     
     
         10 . Equipment integrated for pyrolysis and gasification of waste and its derivatives, according to  claim 2 , characterized by the fact that it is presented as a second variant of the equipment comprising exhaust fan ( 1 . 4 . 1 ) and absence of a combustion chamber ( 1 . 4 ) and direction of the gases drawn by the exhaust fan ( 1 . 4 . 11 ) to the treatment and separation system for combustible fractions, and sent to various energy use processes.