Gasification of carbonaceous solids

Abstract

A continuous process for converting particulate carbonaceous solids to gaseous hydrocarbons (from 1 to 7 carbon atoms per molecule of gas) by the rapid pyrolysis and in situ conversion of a portion of the pyrolysis product comprising heating a turbulent high velocity gaseous stream composed of carrier gas, carbonaceous solids and at least 2.0 weight percent water based upon the weight of carbonaceous solids and heating said stream in a pyrolysis zone at a temperature ranging from between about 1200° F. to about 2400° F. until at least a portion of said solids are converted to the desired gaseous hydrocarbons.

What is claimed is: 
     
       1. A process for producing gaseous hydrocarbons having from 1 to 7 carbon atoms from solid carbonaceous material comprising: a. Forming a turbulent gaseous stream composed of carrier gas, water, char, and particulate carbonaceous solids, said solids having an individual maximum particle dimension of less than 1.0 inch, such that the solids and water are intimately admixed and entrained within the gaseous portion of the stream; said water being present in said stream in an amount which is at least 2.0 weight percent based upon the amount of carbonaceous solids in said stream; said carrier gas containing less than 1% by volume of oxygen;   b. Heating the components of said stream to a temperature ranging from between about 1200° F. and about 2500° F. in a pyrolysis zone for a predetermined residence time so that at least a portion of said carbonaceous solids are converted to gaseous hydrocarbons, containing from 1 to 7 carbon atoms, ethylene comprising at least 20% by volume of said gaseous hydrocarbons;   c. Removing the product stream from the pyrolysis zone;   d. Recovering the gaseous hydrocarbon products.   
     
     
       2. The process of claim 1 wherein the said gaseous stream contains from about 7 to about 18 weight percent water, based upon the weight of carbonaceous solids in the stream. 
     
     
       3. The process of claim 2 wherein said gaseous stream is heated to a temperature ranging from between 1400° F. to about 1600° F. in said pyrolysis zone. 
     
     
       4. The process of claim 1 wherein said stream is heated to a temperature of about 1500° F. in said pyrolysis zone. 
     
     
       5. The process of claim 1 wherein the residence time of the carbonaceous solids in said pyrolysis zone is less than 5 seconds. 
     
     
       6. The process of claim 1 wherein the carbonaceous solids are municipal waste material, sewage sludge, rubber tire scrap, agricultural wastes, manure, crop residue, food processing wastes, industrial wastes, lignocellulose products, and mixtures thereof. 
     
     
       7. The process of claim 2 in which the carbonaceous solids are municipal waste materials. 
     
     
       8. The process of claim 2 wherein said carbonaceous solids are muniuipal waste material, manure, sewage sludge, rubber tire scrap, food processing wastes, agricultural wastes, industrial wastes, lignocellulose products, and mixtures thereof. 
     
     
       9. The process of claim 2 wherein the gaseous hydrocarbons are separated into their component parts. 
     
     
       10. The process of claim 1 wherein the gaseous hydrocarbons produced consist substantially of ethylene. 
     
     
       11. The process of claim 1 wherein a substantial portion of the heat required for pyrolysis of the carbonaceous solids is supplied by utilizing heated char in the gaseous stream. 
     
     
       12. The process of claim 1 wherein a portion of the heat required in the pyrolysis zone is supplied by indirect heating means to heat the carbonaceous solids. 
     
     
       13. The process of claim 2 wherein said carbonaceous solids are rubber scrap. 
     
     
       14. The process of claim 2 wherein a portion of the solids recovered from the product stream is separately heated to a temperature ranging from between about 1500° F. to about 2400° F. and thereafter is recycled through the pyrolysis zone as hot char in the gaseous stream to supply a substantial portion of the heat required in the pyrolysis zone to heat the carbonaceous solids. 
     
     
       15. The process of claim 14 wherein sufficient amounts of heated char are utilized to provide substantially all of the heat required to heat the carbonaceous solids in the pyrolysis zone. 
     
     
       16. The process of claim 14 wherein the carrier gas is a hydrogen enriched gas stream. .Iadd. 17. A process for producing gaseous hydrocarbons having from 1 to 7 carbon atoms from solid carbonaceous material comprising: a. Forming a turbulent gaseous stream composed of carrier gas, water, char, and particulate carbonaceous solids, said solids having an individual maximum particle dimension of less than 1.0 inch, such that the solids and water are intimately admixed and entrained within the gaseous portion of the stream; said water being present in said stream in an amount which is at least 2.0 weight percent based upon the amount of carbonaceous solids in said stream; said carrier gas containing less than 1% by volume of oxygen;   b. Heating the components of said stream to a temperature ranging from between about 1200° F. and about 2500° F. in a pyrolysis zone for a predetermined residence time so that at least a portion of said carbonaceous solids are converted to gaseous hydrocarbons, containing from 1 to 7 carbon atoms;   c. Removing the product stream from the pyrolysis zone;   d. Recovering the gaseous hydrocarbon products. .Iaddend..Iadd. 18. The process of claim 17 wherein the said gaseous stream contains from about 7 to about 18 weight percent water, based upon the weight of carbonaceous solids in the stream. .Iaddend. .Iadd. 19. The process of claim 18 wherein said gaseous stream is heated to a temperature ranging from between 1400° F. to about 1600° F. in said pyrolysis zone. .Iaddend..Iadd. 20. The process of claim 17 wherein said stream is heated to a temperature of about 1500° F. in said pyrolysis zone. .Iaddend..Iadd. 21. The process of claim 17 wherein the residence time of the carbonaceous solids in said pyrolysis zone is less than 5 seconds. .Iaddend..Iadd. 22. The process of claim 17 wherein the carbonaceous solids are municipal waste material, sewage sludge, rubber tire scrap, agricultural wastes, manure, crop residue, food processing wastes, industrial wastes, lignocellulose products, and mixtures thereof. .Iaddend..Iadd. 23. The process of claim 18 in which the carbonaceous solids are municipal waste materials. .Iaddend..Iadd. 24. The process of claim 18 wherein said carbonaceous solids are municipal waste material, manure, sewage sludge, rubber tire scrap, food processing wastes, agricultural wastes, industrial wastes, lignocellulose products, and mixtures thereof. .Iaddend. .Iadd. 25. The process of claim 18 wherein the gaseous hydrocarbons are separated into their component parts. .Iaddend..Iadd. 26. The process of claim 17 wherein the gaseous hydrocarbons produced consist substantially of ethylene. .Iaddend..Iadd. 27. The process of claim 17 wherein a substantial portion of the heat required for pyrolysis of the carbonaceous solids is supplied by utilizing heated char in the gaseous stream. .Iaddend..Iadd. 28. The process of claim 17 wherein a portion of the heat required in the pyrolysis zone is supplied by indirect heating means to heat the carbonaceous solids. .Iaddend..Iadd. 29. The process of claim 18 wherein said carbonaceous solids are rubber scrap. .Iaddend..Iadd. 30. The process of claim 18 wherein a portion of the solids recovered from the product stream is separately heated to a temperature ranging from between about 1500° F. to about 2400° F. and thereafter is recycled through the pyrolysis zone as hot char in the gaseous stream to supply a substantial portion of the heat required in the pyrolysis zone to heat the carbonaceous solids. .Iaddend. .Iadd. 31. The process of claim 30 wherein sufficient amounts of heated char are utilized to provide substantially all of the heat required to heat the carbonaceous solids in the pyrolysis zone. .Iaddend..Iadd. 32. The process of claim 30 wherein the carrier gas is a hydrogen enriched gas stream. .Iaddend.