THIS STUDY ASSESSES WHETHER THE USE OF TESSARIA ABSINTHIOIDES (TA) PELLETS AS A BIOENERGY RESOURCE IS FEASIBLE OR NOT. ITS FUEL PROPERTIES WERE CHARACTERIZED AND ITS COMBUSTION BEHAVIOR ASSESSED VIA A TRADITIONAL LOG WOOD STOVE WITH A BASKET OF WOOD PELLETS. COMBUSTION OF PINEWOOD (PINUS RADIATA) COMMERCIAL PELLETS (CP) WAS USED AS A REFERENCE IN ORDER TO ANALYZE EXPERIMENTAL RESULTS. TA HAS A HIGH ASH CONTENT OF 8.1% AND AN HHV OF 17.47 MJ KG?1. ALKALINE INDEX ON THE TA PELLETS WAS OF 1.46 KG ALKALI GJ?1, A RELATIVELY HIGH VALUE, WHICH RESULTED FROM HIGH SODIUM CONTENT IN ASH. OVEN AND EXHAUST TEMPERATURES DURING THE COMBUSTION OF TA AND CP PRESENT SIMILAR BEHAVIOR. THE COMBUSTION CHAMBER?S HIGHEST TEMPERATURE FOR CP WAS 841.15 °C, WHILE FOR TA, THE HIGHEST TEMPERATURE WAS 685.65 °C. FURTHERMORE, CO AND PM EMISSION WAS SUPERIOR FOR TA PELLETS, AVERAGING ABOUT 4943.6 ± 235.2 MG NM?3 AND 32.45 ± 6.49 MG MJ?1, RESPECTIVELY AT 13% O2. RESULTS OBTAINED HAVE SHOWN THAT THERE WERE NO APPARENT HINDRANCES FOR AN EXTENSIVE USE OF TA AS A BIOENERGY RESOURCE AND USE OF PELLET BASKETS TO COMBUST PELLETS IN TRADITIONAL WOOD LOG STOVES.

THIS PAPER PRESENTS A NOVEL APPROACH TO TACKLE THE DUAL CHALLENGES OF ENERGY SCARCITY AND MUNICIPAL SOLID WASTE MANAGEMENT BY EXPLOITING THE POTENTIAL OF MUNICIPAL SOLID WASTE GASIFICATION. THE PERFORMANCE OF THE MODIFIED UPDRAFT GASIFIER IS EVALUATED USING COMPUTATIONAL MODELING WITH ASPEN PLUS V14 SOFTWARE. THE RELIABILITY OF THE GASIFICATION MODEL IS CONFIRMED BY COMPARING IT WITH EXPERIMENTAL DATA, HIGHLIGHTING ITS ACCURACY IN ESTIMATING KEY GAS COMPOSITION PARAMETERS. A DETAILED ANALYSIS OF THE PERCENTAGE ERROR BETWEEN THE GAS'S EXPERIMENTALLY MEASURED LOWER HEATING VALUE AND THE MODEL-ESTIMATED VALUE IS PERFORMED. RESULTS SHOW A 12.2 % ERROR FOR MUNICIPAL SOLID WASTE GASIFICATION, MEANING THE EXPERIMENTAL LOWER HEATING VALUE IS HIGHER THAN THE MODEL'S ESTIMATION. ON THE OTHER HAND, A 27,2 % ERROR IS OBSERVED FOR PELLET GASIFICATION, IMPLYING A LOWER EXPERIMENTAL LOWER HEATING VALUE THAN THE MODEL'S ESTIMATION. THESE FINDINGS PROVIDE USEFUL INFORMATION FOR FUTURE OPTIMIZATION AND IMPROVEMENT OF THE GASIFICATION PROCESS, FURTHER ADVANCING THE FIELD OF WASTE-TO-ENERGY CONVERSION AND PROMOTING SUSTAINABLE ENERGY GENERATION.

THIS WORK ASSESSES THE EFFECTS OF VARIOUS PROCESS TEMPERATURES (700, 750, AND 800 °C) AND EQUIVALENCE RATIO (0.25; 0.30 AND 0.35) ON GASIFICATION OF GRAPEFRUIT (CITRUS X PARADISI) SOLID WASTE (GSW) IN A FLUIDIZED BED REACTOR. THE EXPERIMENTAL RESULTS PERMIT THE CONSTRUCTION AND FIT TRIDIMENSIONAL CHART TO ASSESS THE STUDIED MAIN OUTPUT VARIABLES' BEHAVIOR FOR THE SIMULTANEOUS VARIATION OF EQUIVALENCE RATIO AND PROCESS TEMPERATURE. THE BETTER PRODUCER GAS COMPOSITION FOR THE GRAPEFRUIT SOLID WASTE GASIFICATION WAS OBTAINED FOR A PROCESS TEMPERATURE OF 800 °C AND 0.25 EQUIVALENCE RATIO; THE GAS YIELDS AROUND 67%, WITH LHV OF 4389 KJ/NM3, WITHIN THE SPECTRUM OF VALUES REPORTED FOR OTHER LIGNOCELLULOSIC RESIDUES. ACCORDING TO THE OBTAINED STUDY RESULTS, GSW PRESENTS A VALUABLE RENEWABLE ENERGY RESOURCE FOR AGROINDUSTRY. FOR OPERATION PARAMETERS ASSESSED, COULD BE POTENTIALLY PRODUCED 3.49 GJ OF THERMAL ENERGY PER TON OF GSW GASIFIED.

THIS STUDY PRESENTS AN ECONOMICAL AND ENVIRONMENTAL APPRAISAL OF THE BIOMASS INTEGRATED GASIFICATION/GAS TURBINE COMBINED CYCLE (BIG-GTCC) INTRODUCTION IN A BRAZILIAN SUGARCANE MILL TO INCREASE THE MILL POWER GENERATION POTENTIAL. THE ANALYSIS CONSIDERS THE INTRODUCTION OF TORREFACTION TECHNOLOGY AS A PRETREATMENT PROCEDURE FOR WET BAGASSE TO SETTLE THE FEEDING PROBLEMS EXPERIENCED DURING THE GASIFIER CONTINUOUS OPERATION USING THIS POWDERED FEEDSTOCK. THE ENVIRONMENTAL IMPACTS AFTER INTEGRATING THE BIG-GTCC TECHNOLOGY WERE DETERMINED USING THE LIFE CYCLE ASSESSMENT. WHEN ANALYZED FOR THE BEHAVIOR OF EXPECTED ANNUAL REVENUE IN BOTH CONFIGURATIONS, THE IMPLEMENTATION OF GASIFICATION OF THE SURPLUS VOLUME OF THE PLANT BAGASSE APPEARS AS THE BEST OPTION FROM AN ECONOMIC AND ENVIRONMENTAL VIEWPOINT.

PRODUCER GAS FROM BIOMASS GASIFICATION OFFERS A RENEWABLE ALTERNATIVE TO FOSSIL FUELS. HOWEVER, ITS LOW ENERGY DENSITY RESULTS IN LOW CONVERSION EFFICIENCY IN ENGINES. BLENDING PRODUCER GAS WITH HIGHER-RANKED FUELS SUCH AS HYDROGEN HAS BEEN PROPOSED TO OVERCOME THIS ISSUE. THIS STUDY INVESTIGATES THE COMBUSTION OF ARTIFICIALLY MADE PRODUCER GAS AND HYDROGEN MIXTURES IN AN OPTICAL SI ENGINE. THE MOLAR FRACTION OF HYDROGEN IN PRODUCER GAS RANGED FROM 14 TO 62%, WHICH SIMULATED ADDITIONS OF HYDROGEN TO A LOW CALORIFIC PRODUCER GAS. THE EXPERIMENTS ARE CONDUCTED AT A CONSTANT SPEED AND STOICHIOMETRIC RATIO. THE SPARK TIMING IS VARIED TO ACHIEVE THE HIGHEST POWER FOR EACH MIXTURE. RESULTS INCLUDE DATA ON EMISSIONS, THERMODYNAMICS, AND FLAME MORPHOLOGY. THE MOLAR FRACTION OF 33% HYDROGEN ON PRODUCER GAS IMPROVES THE FLAME MORPHOLOGY OF THE MIXTURE TO RESEMBLE THAT OF PURE NATURAL GAS, WHILE 24?36% WAS FOUND TO BE THE OPTIMAL RANGE FOR ENGINES INITIALLY DESIGNED TO RUN ON NATURAL GAS WITH LOWER NOX AND UHC EMISSIONS.

THERMAL PROCESSES AND POWER GENERATION SYSTEMS MAY EMPLOY PRODUCER GAS GENERATED THROUGH GASIFICATION AS AN ALTERNATIVE TO REPLACE NATURAL GAS WITH LOWER CARBON FOOTPRINT. HOWEVER, PURE PRODUCER GAS IN ENGINES IS ASSOCIATED WITH A SIGNIFICANT POWER DERATING THAT CAN BE MITIGATED BY BLENDING IT WITH OTHER BIOFUELS. THIS WORK EVALUATED THE EFFECTS OF METHANE AND PRODUCER GAS BLENDS ON THE PERFORMANCE OF A SI ENGINE. THE ADDITIONS OF METHANE WERE 10%, 25% AND 50% ON A MOLAR BASIS. THE RESULTS DEMONSTRATED THAT ADDING 25% METHANE TO PRODUCER GAS IS ENOUGH TO SUSTAIN THE COMBUSTION REACTION WITH GOOD STABILITY AND A POWER DERATING OF 10.8%. THE ADDITION OF 50% METHANE TO PRODUCER GAS ATTAINS EFFICIENCY AND COMBUSTION CHARACTERISTICS REMARKABLY SIMILAR TO PURE NATURAL GAS WITH A POWER DE-RATING OF 5.4%. EMISSIONS INDICATED THAT CARBON MONOXIDE (CO) HAS DECREASED WITH THE ADDITION OF METHANE TO PRODUCER GAS FROM 85 TO 3.43 G/KWH, WHILE NITROGEN OXIDES (NOX) EMISSIONS HAVE INCREASED FROM 0 TO 8.85 G/KWH. IN THE CASE OF UNBURNED HYDROCARBONS (UHC), EMISSIONS DID NOT CONSIDERABLY CHANGE BEFORE ADDING 25% METHANE TO PRODUCER GAS AND STAYED CONSTANT AT APPROXIMATELY 10 G/KWH. ENGINES DESIGNED TO RUN ON NATURAL-GAS COULD USE THIS MIXTURE WITHOUT SIGNIFICANT MODIFICATIONS TO THE COMBUSTION CHAMBER WHILE DECREASING NOX EMISSIONS.

LA INDUSTRIA PROCESADORA DE LA NARANJA GENERA ELEVADOS VOLÚMENES DE RESIDUOS SÓLIDOS. ESTE RESIDUO SE HA UTILIZADO COMO COMPLEMENTO EN LA ALIMENTACIÓN ANIMAL, EN PROCESOS BIOQUÍMICOS; PERO EXISTEN POCOS ESTUDIOS QUE VALOREN SU APROVECHAMIENTO ENERGÉTICO POR MEDIO DEL PROCESO DE GASIFICACIÓN Y ADEMÁS DE LA INFLUENCIA DEL USO DE CATALIZADORES EN EL PROCESO DE LIMPIEZA DE GASES. SE REALIZARON ESTUDIOS DE GASIFICACIÓN CON AIRE EN LECHO FLUIDIZADO CATALÍTICOS (UTILIZANDO DOLOMITA Y OLIVINO COMO CATALIZADORES EN UN REACTOR SECUNDARIO, VARIANDO ADEMÁS LA TEMPERATURA DEL REACTOR SECUNDARIO Y LA MASA DE CATALIZADOR), DE LOS RESIDUOS SÓLIDOS DE NARANJA (RSN) Y SE COMPARAN LOS RESULTADOS CON LOS OBTENIDOS EN LA GASIFICACIÓN CON AIRE NO CATALÍTICA. PARA ESTABLECER LAS CONDICIONES EN QUE SE REALIZARON LOS ESTUDIOS Y VALORAR LOS RESULTADOS EN LOS PROCESOS SE UTILIZÓ UN DISEÑO DE EXPERIMENTO FACTORIAL COMPLETO DE 2K, VALORANDO LA INFLUENCIA DE LAS VARIABLES INDEPENDIENTES Y SUS INTERACCIONES EN LAS RESPUESTAS, UTILIZANDO EL SOFTWARE DESIGN-EXPERT® Y UN GRADO DE SIGNIFICACIÓN DEL 95 %. LOS RESULTADOS DEMUESTRAN LAS CUALIDADES DE LOS RSN EN EL APROVECHAMIENTO ENERGÉTICO POR MEDIO DEL PROCESO DE GASIFICACIÓN PARA EL TRATAMIENTO DE ESTOS RESIDUOS, OBTENIENDO UN GAS DE BAJO PODER CALORÍFICO. ADEMÁS, EL USO DE CATALIZADORES DISMINUYE EL RENDIMIENTO DE ALQUITRANES OBTENIDOS EN EL PROCESO DE GASIFICACIÓN, SIENDO MÁS ACTIVA LA DOLOMITA QUE EL OLIVINO CON ESTE FIN. LOS MEJORES RESULTADOS DE LA GASIFICACIÓN CATALÍTICA EN LECHO FLUIDIZADO DE LOS RSN, EN LO REFERENTE A PODER CALORÍFICO DEL GAS, RENDIMIENTO EN EL GAS Y BAJO RENDIMIENTO DE ALQUITRÁN, SE OBTIENE CUANDO EL REACTOR SECUNDARIO OPERA A UNA TEMPERATURA DE 800 ºC Y EMPLEANDO 60 G DE DOLOMITA COMO CATALIZADOR

SUGARCANE BAGASSE IS USED AS ENERGY SOURCE IN THE SUGAR CANE INDUSTRY. AN APPROPRIATE CHARACTERIZATION OF THEIR PHYSICAL AND MORPHOLOGICAL PROPERTIES IS VITALLY IMPORTANT FOR THEIR USE IN THE GASIFICATION AND COMBUSTION PROCESSES. THIS WORK MAKES A STUDY OF THE SIZE AND SHAPE DISTRIBUTION OF THE BAGASSE GENERATED IN A SUGARCANE MILL BASED UPON TWO IMPORTANT FACTORS THAT INFLUENCE THEIR PHYSICAL PROPERTIES, SUCH AS ASPECT RATIO (AR) AND SPHERICITY. THE DISTRIBUTION OF THE GRAIN SIZES HAS BEEN DETERMINED FOR THE ANALYZED SAMPLES; THE SHAPES OF THE PARTICLES HAS BEEN DETERMINED BY A MANUAL METHOD AND THROUGH AN IMAGE-ANALYSIS METHOD, USING THE IMAGEJ SOFTWARE. IT HAS BEEN OBSERVED THAT SUGARCANE BAGASSE HAS A LARGER LENGTH THAN THE OTHER ANALYZED BIOMASSES, WITH AN ALMOST SIMILAR WIDTH. THE ASPECT RATIO WAS BETWEEN 2.14 AND 5.5 FOR ALL THE STUDIED SIZE RANGES (9.5?0.15?MM). FOR PARTICLES WITH DIAMETERS SMALLER THAN 0.3?MM, THE ASPECT RATIO HAS A SIMILAR BEHAVIOR TO THE OTHER BIOMASSES, WITH A REPORTED VALUE OF 2.5. THE DETERMINED SPHERICITY WAS BETWEEN 0.27 AND 0.558, WITH A MEAN VALUE OF 0.397.

TORREFACTION HAS EMERGED AS A PROMISING TECHNOLOGY FOR OPTIMIZING THE EFFICIENCY OF THERMOCHEMICAL PROCESSES. HOWEVER, MANY CHALLENGES STILL NEED TO BE ADDRESSED REGARDING ITS INTEGRATION WITH OTHER PROCESSES, SUCH AS GASIFICATION. THIS WORK INVESTIGATES THE POTENTIAL OF TORREFACTION TO TRANSFORM THE PROPERTIES OF BIOMASS MIXTURES, IMPROVING OPERATIONS IN FLUIDIZED BED REACTORS. EXPERIMENTALLY, HAZELNUT SHELLS AND OLIVE PIT MIXTURES WERE TORREFIED AT 280 ?C FOR 45 MIN TO ANALYZE HOW TORREFACTION AFFECTED THE MINIMUM FLUIDIZATION VELOCITY AS A BULK DENSITY FUNCTION. THE RESULTS WERE COMPARED TO OTHER BIOMASSES FROM THE LITERATURE. OUR FINDINGS SHOW THAT TORREFACTION CAN STABILIZE MINIMUM FLUIDIZATION VELOCITY AT 0,45 M/S FOR MIXTURES OF BIOMASSES WITH BULK DENSITIES BELOW 700 KG/M3 AND PARTICLE SIZE RANGE (T) OF 1,7 < T < 2,36 × 10? 3 M. THESE FINDINGS COLLECTIVELY EMPHASIZE THE POTENTIAL OF TORREFACTION AS AN EFFECTIVE TECHNOLOGY FOR UTILIZING AGRO-INDUSTRIAL RESIDUES IN ENERGY GENERATION PROCESSES NOT ONLY FOR THE IMPROVEMENT OF CONVERSION EFFICIENCY BUT ALSO FOR OPERATION STABILITY.

THE INDUSTRY PROCESSING OF THE ORANGE GENERATES HIGH VOLUMES OF SOLID WASTE. THIS WASTE HAS BEEN USED TO COMPLEMENT ANIMAL FEEDING AND BIOCHEMICAL PROCESSES, BUT THE GASIFICATION PROCESS HAS NOT VALUED ITS ENERGY USE. GASIFICATION STUDIES WERE CARRIED OUT WITH AIR IN A CATALYTIC FLUIDIZED BED (USING DOLOMITE AND OLIVINE AS CATALYSTS IN A SECONDARY REACTOR, ALSO VARYING THE TEMPERATURE OF THE SECONDARY REACTOR AND THE CATALYST MASS) OF THE SOLID WASTE OF ORANGE, AND THE RESULTS ARE COMPARED WITH THOSE OBTAINED IN THE GASIFICATION WITH NON-CATALYTIC AIR. IN THE PROCESSES, WE USE A DESIGN OF A COMPLETE FACTORIAL EXPERIMENT OF 2K, VALUING THE INFLUENCE OF THE INDEPENDENT VARIABLES AND THEIR INTERACTIONS IN THE ANSWERS, USING THE SOFTWARE DESIGN-EXPERT® AND A GRADE OF THE SIGNIFICANCE OF 95 %. THE RESULTS DEMONSTRATE THE QUALITIES OF THE SOLID WASTE OF ORANGE IN THE ENERGY USE THROUGH THE GASIFICATION PROCESS FOR THE TREATMENT OF THESE RESIDUALS, OBTAINING A GAS OF LOW HEATING VALUE. THE USE OF CATALYSTS ALSO DIMINISHES THE YIELD OF TARS OBTAINED IN THE GASIFICATION PROCESS, MAKING DOLOMITE MORE ACTIVE THAN OLIVINE. THE BETTER RESULTS OF FLUIDIZED BED CATALYTIC GASIFICATION OF RSNS, IN TERMS OF GAS HEATING VALUE, GAS YIELD, AND LOW TAR YIELD, ARE OBTAINED WHEN THE SECONDARY REACTOR OPERATES AT A TEMPERATURE OF 800 ºC AND USING 60 G OF DOLOMITE AS A CATALYST.

THE HIGH ENVIRONMENTAL IMPACT OF FOSSIL FUELS COMBINED WITH THE RISE OF CARBON DIOXIDE IN THE ATMOSPHERE HAS MADE THE SEARCH FOR RENEWABLE FUELS IMPERATIVE. THE STUDY ASSESSES THE TECHNICAL AND ECONOMIC VIABILITY OF REPLACING HEAVY FUEL OIL (HFO) WITH GREEN HYDROGEN (H2) IN INDUSTRIAL PLANTS FOR HIGH TEMPERATURE GENERATION (>1100 K). THE STUDY ALSO ESTIMATES THE EMISSIONS GENERATED BY THE PLANTS AFTER THE FUEL SWITCH IN TERMS OF PARTICULATE MATTER (PM), SO2, NOX AND CO2 EMISSIONS. TO ILLUSTRATE THE FEASIBILITY OF THIS REPLACEMENT, AN ASSESSMENT OF A CALCINATION FURNACE AT A PULP PLANT IN CHILE IN 2022 WAS CARRIED OUT, TAKING INTO ACCOUNT TWO ELECTRICITY GENERATION SCENARIOS FOR H2 PRODUCTION BY WATER ELECTROLYSIS. REPLACING HFO WITH A MIXTURE OF H2 + HFO WAS BENEFICIAL IN TERMS OF EMISSIONS. THE FINANCIAL ASSESSMENT SHOWED THAT BLENDING H2 WITH HFO OF UP TO 20 % IS THE BEST SOLUTION, CONSIDERING CURRENT FUEL PRICES, AND THAT FULL SUBSTITUTION OF HFO WITH H2 AFTER 2030 IS ECONOMICALLY VIABLE.

THE UTILIZATION OF HYDROGEN AS AN ENERGY CARRIER FACES A CHALLENGE DUE TO ITS LIMITED PRESENCE IN ITS PURE FORM IN THE EARTH

ADVANCES IN WASTE-TO-ENERGY TECHNOLOGY AND SUSTAINABLE FUEL PRODUCTION DRIVE SIGNIFICANT CHANGES IN THE ENERGY INDUSTRY. THESE INNOVATIVE SOLUTIONS NOT ONLY ADDRESS WASTE MANAGEMENT CHALLENGES BUT ALSO CONTRIBUTE TO BROADENING THE ENERGY SOURCE MATRIX AND REDUCING DEPENDENCE ON TRADITIONAL FOSSIL FUELS. THIS STUDY EVALUATES THE INCORPORATION OF POLYETHYLENE AND POLYPROPYLENE URBAN PLASTIC WASTE IN VARIOUS AGRO-INDUSTRIAL BY-PRODUCT BLENDS, WHICH COMBINE BEET PULP, RADIATA PINE, AND EUCALYPTUS BARK WASTES. THE GENERATION OF THE HYBRID BIOFUEL FROM AGRO-INDUSTRIAL WASTE AND DOMESTIC SOLID WASTE IN PELLET FORM IS INVESTIGATED TO DETERMINE THE OPTIMAL BLENDS IN TERMS OF DURABILITY, ASH GENERATION AND CALORIFIC VALUE. BOTH URBAN PLASTICS INCORPORATED IN THE MIXTURES NOT ONLY SIGNIFICANTLY INCREASE THE CALORIFIC ENERGY VALUE BUT ALSO PROMOTE THE BINDING OF THE SOLID BIOFUEL COMPONENTS. THE POLYPROPYLENE-BASED URBAN PLASTIC PELLET EXHIBITED SUPERIOR BINDING CAPACITY AND LOWER ASH GENERATION, EVEN IN COMPLEX HYDROXYL FUNCTIONAL GROUPS. IT ALSO DISPLAYED SUITABLE PROPERTIES FOR SOLID BIOFUELS, SUCH AS LOW FINE CONTENT, HIGH DURABILITY, AND DIMENSIONAL STABILITY. THE HIGHEST RESULTING CALORIFIC VALUE OF 22.6 MJ/KG WAS DETERMINED FOR THE MASS RATIO OF THE BLEND WITH 99% DURABILITY, 0.23% FINES CONTENT, AND 5.1% COMBUSTION ASH GENERATION. THIS NEW HYBRID BIOFUEL IS PRESENTED AS A SUSTAINABLE OPTION AND A SIGNIFICANT CONTRIBUTION IN THE FIELD OF WASTE-TO-ENERGY TECHNOLOGY AND RENEWABLE ENERGY PRODUCTION. THE PRODUCTION COST OF THE HYBRID BIOFUEL IS COMPETITIVE WITH WOOD-BASED BIOFUELS, WITH ONLY A 6.25% INCREASE OBSERVED FOR PELLETS MADE FROM 50% WOOD AND 20% BEET PULP COMPARED TO TRADITIONAL 100% WOOD PELLETS. HOWEVER, SIGNIFICANT COST REDUCTIONS WERE ACHIEVED THROUGH SPECIFIC CONFIGURATIONS, RESULTING IN SAVINGS OF 14.8%. THE NOVEL HYBRID BIOFUEL REQUIRES ONLY 9.2 MJ/KG TO PRODUCE 22.6 MJ/KG, DEMONSTRATING SIGNIFICANT ENERGY IMPACT AND VIABILITY AS A SUSTAINABLE ENERGY SOURCE

SUGARCANE BAGASSE HAS A GREAT POTENTIAL TO BE USED AS BIOFUEL; HOWEVER, ITS USE AS FEEDSTOCK IN FLUIDIZED BED REACTORS IS HAMPERED DUE TO ITS FIBROUS NATURE, LOW APPARENT DENSITY, HIGH MOISTURE CONTENT, AND DIFFICULTIES WITH ITS FLUIDIZATION. THE PRESENT STUDY EVALUATED THE TORREFACTION OF SUGARCANE BAGASSE TO PROPOSE SUITABLE PROCESS CONDITIONS THAT BALANCE THE PROPERTIES OF THE FUEL OBTAINED IN THE TORREFACTION AND THE PROCESS?S ENERGY REQUIREMENTS. BASED ON THE THERMOGRAVIMETRIC ANALYSIS AND PREVIOUS REPORTS, TWO FINAL PROCESS TEMPERATURES (230 °C AND 280 °C) AND RESIDENCE TIMES (35 AND 45 MIN) FOR THE SAME HEATING RATE (5 °C/MIN) AND NITROGEN FLOW (1 L/MIN) WERE EVALUATED. WITHIN THE EXPERIMENTAL CONDITIONS EVALUATED, IT CAN BE CONCLUDED THAT FOR 30 MIN OF RESIDENCE TIME, THE AVERAGE TARGET TEMPERATURE OF 230 °C SHOULD BE HIGH ENOUGH TO PRODUCE A STABLE TORREFACTED BAGASSE WITH A 3.41% REDUCTION IN THE VOLATILE CONTENT AND OBTAIN 98.85% OF ENERGY YIELD. HIGHER TEMPERATURES INCREASE THE FEEDSTOCK?S CARBON CONTENT AND ENERGY DENSITY, BUT THE REDUCTION IN ENERGY YIELD AND THE FRACTION OF VOLATILES DO NOT JUSTIFY HIGHER TEMPERATURES OR LONGER RESIDENCE TIMES FOR PRETREATING THE SUGARCANE BAGASSE.

IN 2019, CHILE GENERATED 20 MILLION TONS OF WASTE, 79% OF WHICH WAS NOT PROPERLY DISPOSED OF, THEREBY PROVIDING AN ATTRACTIVE OPPORTUNITY FOR ENERGY GENERATION IN ADVANCED THERMOCHEMICAL CONVERSION PROCESSES. THIS STUDY PRESENTS A TECHNO-ECONOMIC AND ENVIRONMENTAL ASSESSMENT OF THE IMPLEMENTATION OF WASTE-INTEGRATED GASIFIER-GAS TURBINE COMBINED CYCLE (WIG-GTCC) TECHNOLOGY AS AN ALTERNATIVE FOR MUNICIPAL SOLID WASTE (MSW) TREATMENT. THE STUDIED CASE ASSESSES THE CONVERSION OF 14.61 T·H?1 OF MSW, WHICH PRODUCES A COMBUSTIBLE GAS WITH A FLOW RATE OF 34.2 T·H?1 AND LHV OF 5900 KJ·KG?1, WHICH, IN TURN, IS USED IN A COMBINED CYCLE TO GENERATE 19.58 MW OF ELECTRICAL POWER. THE PROPOSED ECONOMIC ASSESSMENT OF THE TECHNOLOGY USES THE ENERGY GENERATION PROCESSES AS A REFERENCE, FOLLOWED BY A MODEL FOR AN OVERALL ECONOMIC EVALUATION. THE RESULTS HAVE SHOWN THAT THE PROFIT COULD BE UP TO USD 24.1 MILLION, AND THE RECOVERY OF INVESTMENT BETWEEN 12 AND 17 YEARS WOULD IMPROVE THE ENVIRONMENTAL IMPACTS OF THE CURRENT DISPOSAL TECHNOLOGY. THE WIG-GTCC HAS THE MOST EFFICIENT CONVERSION ROUTE, EMITTING 0.285 KG CO2 EQ/KWH, WHICH REPRESENTS 48.21% OF THE POTENTIAL YIELD OF GLOBAL WARMING OVER 100 YEARS (GWP100) OF INCINERATION AND 58.51% OF THE GWP100 OF THE STANDARD GASIFICATION METHOD. THE WIG-GTCC WOULD ENABLE THE ENERGETIC VALORIZATION OF MSW IN CHILE, ELIMINATE PROBLEMS ASSOCIATED WITH LANDFILL DISPOSAL, AND INCREASE OPPORTUNITIES FOR DECENTRALIZED ELECTRICITY GENERATION.

AN EVALUATION OF THE ENERGY POTENTIAL OF ORGANIC WASTE CALLED SLUMGUM, GENERATED IN THE BEE-WAX INDUSTRY, IS DEVELOPED. THE MAIN OBJECTIVE IS TO DETERMINE WHETHER THIS WASTE CAN BE USED AS FUEL TO GENERATE THE STEAM REQUIRED IN THE PLANT, CONSIDERING ITS COMBUSTION IN A FLUIDIZED BED BOILER. CURRENTLY, THERE ARE NO STUDIES IN THE LITERATURE ASSOCIATED WITH THE USE OF SLUMGUM FOR ENERGY PURPOSES; ONLY ITS USE FOR AGRICULTURAL PURPOSES IS STUDIED, THUS HIGHLIGHTING THE NOVELTY OF THE PRESENT RESEARCH. THE SLUMGUM S MAIN PHYSICAL?CHEMICAL AND ENERGY PROPERTIES ARE DETERMINED, COMPLEMENTING THE INFORMATION AVAILABLE IN THE LITERATURE AND MATHEMATICAL CORRELATIONS, OBTAINING A HIGHER HEATING VALUE OF 17,076 MJ/KG IN THE DRY BASE. AN ENERGY BALANCE WAS MADE IN THE BOILER, CONSIDERING A BUBBLING FLUIDIZED BED SYSTEM S OPERATING CONDITIONS. RESULTS SHOW THAT FOR TYPICAL TEMPERATURE VALUES IN THE HEARTH OF 850 °C AND EXCESS AIR OF 20%, ONLY 25% OF THE HEAT RELEASED IN COMBUSTION IS USED TO GENERATE STEAM; THE REST IS LOST AS SENSIBLE HEAT IN THE EXHAUST GASES. THE PLANT S STEAM DEMAND COULD BE FULLY SATISFIED USING THE SENSIBLE GASES HEAT, FEEDING 1.778 KG OF SLUMGUM OF 8.000 KG PRODUCED DURING THE ALL SEASON, INDICATING THAT 77% OF THE FEEDSTOCK REMAIN AS ENERGY RESERVE. THE PROPOSED PROCESSS ENERGY-ECOLOGIC-EFFICIENCY IS 0,8; THE ECONOMIC SAVINGS OBTAINED BY FUEL REPLACEMENT, TAKING NATURAL GAS AS A REFERENCE, CORRESPONDS TO 716 USD PER SEASON.

IN THIS WORK, THREE MATHEMATICAL MODELS WERE DEVELOPED TO STUDY THE LAMINAR JET DIFFUSION FLAME IN MIXTURES OF NATURAL GAS, HYDROGEN, AND CO2 BY EXTENDING AND APPLYING ROPER