Inventor · disambiguated record
Chang Y. Cha
Also filed as: BARTEL WILLIAM J · CHA CHANG Y · CHA CHANG YUL
72 granted patents·8 pending applications·2,900 citations·filing 1974–2022
99Inventor score
Top patents by PatentIndex Score
80 records- 0199US4140181ATwo-stage removal of sulfur dioxide from process gas using treated oil shaleOCCIDENTAL OIL SHALE INC·Filed 1977·Granted Feb 20, 1979·239 cites·31 claims
- 0299US4005752AMethod of igniting in situ oil shale retort with fuel rich flue gasOCCIDENTAL PETROLEUM CORP·Filed 1975·Granted Feb 1, 1977·404 cites·13 claims
- 0397US3941421AApparatus for obtaining uniform gas flow through an in situ oil shale retortOCCIDENTAL PETROLEUM CORP·Filed 1974·Granted Mar 2, 1976·182 cites·4 claims
- 0495US5087269AInclined fluidized bed system for drying fine coalWESTERN RESEARCH INST·Filed 1990·Granted Feb 11, 1992·95 cites·66 claims
- 0595US4437519AReduction of shale oil pour pointOCCIDENTAL OIL SHALE INC·Filed 1981·Granted Mar 20, 1984·229 cites·14 claims
- 0695US4014575ASystem for fuel and products of oil shale retortOCCIDENTAL PETROLEUM CORP·Filed 1974·Granted Mar 29, 1977·150 cites·10 claims
- 0794US5389691AProcess for co-recycling tires and oilsUNIV WYOMING·Filed 1993·Granted Feb 14, 1995·77 cites·16 claims
- 0892US6592723B2Process for efficient microwave hydrogen productionFiled 2001·Granted Jul 15, 2003·45 cites·12 claims
- 0992US4149595AIn situ oil shale retort with variations in surface area corresponding to kerogen content of formation within retort siteOCCIDENTAL OIL SHALE INC·Filed 1977·Granted Apr 17, 1979·43 cites·26 claims
- 1090US5536477APollution arrestorCHANG YUL CHA·Filed 1995·Granted Jul 16, 1996·93 cites·2 claims
- 1190US4983278APyrolysis methods with product oil recyclingWESTERN RESEARCH INST & ILR SE·Filed 1989·Granted Jan 8, 1991·182 cites·19 claims
- 1288US6187988B1Process for microwave decomposition of hazardous matterFiled 1999·Granted Feb 13, 2001·79 cites·18 claims
- 1387US5041209AProcess for removing heavy metal compounds from heavy crude oilWESTERN RESEARCH INST·Filed 1989·Granted Aug 20, 1991·70 cites·8 claims
- 1486US5198084ALow-cost process for hydrogen productionWESTERN RESEARCH INST·Filed 1989·Granted Mar 30, 1993·36 cites·11 claims
- 1585US6783632B2Process for efficient microwave hydrogen productionFiled 2003·Granted Aug 31, 2004·24 cites·17 claims
- 1684US6284202B1Device for microwave removal of NOx from exhaust gasCHA CORP·Filed 2000·Granted Sep 4, 2001·40 cites·5 claims
- 1784US5171406AFluidized bed selective pyrolysis of coalWESTERN RESEARCH INST·Filed 1990·Granted Dec 15, 1992·43 cites·9 claims
- 1882US5767470AProcess and device for removal of combustion pollutants under high oxygen conditionsFiled 1997·Granted Jun 16, 1998·49 cites·9 claims
- 1981US5735948AProcess for co-recycling tires and oilsUNIV WYOMING·Filed 1995·Granted Apr 7, 1998·42 cites·7 claims
- 2081US5470384AProcess for co-recycling tires and oilsUNIV WYOMING·Filed 1994·Granted Nov 28, 1995·33 cites·15 claims
- 2180US8168126B2Apparatus for microwave induced destruction of siloxanes and hydrogen sulfide in biogasCHA CHANG YUL·Filed 2011·Granted May 1, 2012·3 cites·21 claims
- 2280US4192381AIn situ retorting with high temperature oxygen supplying gasOCCIDENTAL OIL SHALE INC·Filed 1978·Granted Mar 11, 1980·20 cites·29 claims
- 2379US6830662B2Process for microwave destruction of harmful agents and wasteFiled 2002·Granted Dec 14, 2004·24 cites·8 claims
- 2479US6419799B1Process for microwave gas purificationFiled 2000·Granted Jul 16, 2002·25 cites·14 claims
- 2579US5164054ALow-cost process for hydrogen productionCHA CHANG Y·Filed 1991·Granted Nov 17, 1992·29 cites·10 claims
- 2678US7641874B2Microwave induced destruction of impurities from biogas and nitrogen oxides from engine exhaustCHA CORP·Filed 2008·Granted Jan 5, 2010·6 cites·10 claims
- 2778US4369842AAnalyzing oil shale retort off-gas for carbon dioxide to determine the combustion zone temperatureOCCIDENTAL OIL SHALE INC·Filed 1981·Granted Jan 25, 1983·49 cites·15 claims
- 2877US4223726ADetermining the locus of a processing zone in an oil shale retort by effluent water compositionOCCIDENTAL OIL SHALE INC·Filed 1979·Granted Sep 23, 1980·39 cites·30 claims
- 2977US3994343AProcess for in situ oil shale retorting with off gas recyclingOCCIDENTAL PETROLEUM CORP·Filed 1974·Granted Nov 30, 1976·29 cites·38 claims
- 3075US4076312AMethod and apparatus for retorting oil shale at subatmospheric pressureOCCIDENTAL OIL SHALE INC·Filed 1976·Granted Feb 28, 1978·16 cites·16 claims
- 3173US8653148B2Microwave process and apparatus for breaking emulsionsCHA CHANG YUL·Filed 2010·Granted Feb 18, 2014·2 cites·6 claims
- 3273US4227574ALocating the top of an in situ oil shale retort for ease of ignitionOCCIDENTAL OIL SHALE INC·Filed 1979·Granted Oct 14, 1980·15 cites·9 claims
- 3373US4192552AMethod for establishing a combustion zone in an in situ oil shale retort having a pocket at the topCHA CHANG Y·Filed 1978·Granted Mar 11, 1980·15 cites·58 claims
- 3472US4163475ADetermining the locus of a processing zone in an in situ oil shale retortOCCIDENTAL OIL SHALE INC·Filed 1978·Granted Aug 7, 1979·34 cites·18 claims
- 3571US4105072AProcess for recovering carbonaceous values from post in situ oil shale retortingOCCIDENTAL OIL SHALE INC·Filed 1977·Granted Aug 8, 1978·14 cites·45 claims
- 3670US7303684B2Process for microwave alternative destruction-adsorptionCHA CHANG YUL·Filed 2004·Granted Dec 4, 2007·12 cites·19 claims
- 3769US8431083B2Microwave induced destruction of siloxanes and hydrogen sulfide in biogasCHA CHANG YUL·Filed 2012·Granted Apr 30, 2013·1 cites·9 claims
- 3869US6027698AProcess and device for removal of combustion pollutants under high oxygen conditionsFiled 1998·Granted Feb 22, 2000·29 cites·6 claims
- 3969US4191251AProcess for recovering carbonaceous values from in situ oil shale retortingOCCIDENTAL OIL SHALE INC·Filed 1978·Granted Mar 4, 1980·13 cites·77 claims
- 4069US4036299AEnriching off gas from oil shale retortOCCIDENTAL OIL SHALE INC·Filed 1975·Granted Jul 19, 1977·29 cites·47 claims
- 4168US7960303B2Microwave induced destruction of siloxanes and hydrogen sulfide in biogasCHA CORP·Filed 2008·Granted Jun 14, 2011·2 cites·8 claims
- 4268US6207023B1Process for microwave air purificationFiled 1999·Granted Mar 27, 2001·32 cites·20 claims
- 4368US5246554AProcess for selected gas oxide removal by radiofrequency catalystsCHA CHANG Y·Filed 1991·Granted Sep 21, 1993·29 cites·2 claims
- 4467US4263970AMethod for assuring uniform combustion in an in situ oil shale retortOCCIDENTAL OIL SHALE INC·Filed 1978·Granted Apr 28, 1981·11 cites·104 claims
- 4566US5451302AProcess for microwave catalysis of chemical reactions using waveguide liquid filmsFiled 1994·Granted Sep 19, 1995·15 cites·6 claims
- 4666US2010143209A1Microwave induced destruction of impurities from biogas and nitrogen oxides from engine exhaustCHA CORP·Filed 2009·Application pending·0 cites
- 4765US8771503B2Process and system for recovering oil from tar sands using microwave energyCHA CHANG YUL·Filed 2009·Granted Jul 8, 2014·4 cites·15 claims
- 4864US2024375952A1Microwave Cracking of HydrocarbonsCHA CORP·Filed 2022·Application pending·0 cites
- 4962US4246965AMethod for operating an in situ oil shale retort having channellingOCCIDENTAL OIL SHALE INC·Filed 1979·Granted Jan 27, 1981·23 cites·64 claims
- 5061US4243100AOperation of in situ oil shale retort with void at the topOCCIDENTAL OIL SHALE INC·Filed 1979·Granted Jan 6, 1981·14 cites·31 claims
Showing the top 50 of 80 patent records by PatentIndex Score.
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