pyrolysis and gasification of solid wastes in … fluidization south africa fluidization into the...

Industrial Fluidization South AfricaIndustrial Fluidization South AfricaFluidization into the Future

Pyrolysis and Pyrolysis and GasificationGasificationof of SolidSolid WastesWastes

in in FluidizedFluidized BedBed ReactorsReactors

Umberto ARENAUmberto ARENA and Maria Laura and Maria Laura MASTELLONEMASTELLONE

Dep. of Dep. of EnvirEnvir. Sciences . Sciences –– University of Naples IIUniversity of Naples II

AMRA AMRA s.c.as.c.a r.lr.l. .

Necessity of Alternatives to Necessity of Alternatives to Landfill and IncinerationLandfill and Incineration

LANDFILLLANDFILL with its many drawbacks is yet the preferred option in many, even industrialised, countries, even though there are several Statesthere are several States in Europe and Asia that are in heavy difficulties to find landfill sitesthat are in heavy difficulties to find landfill sites, due to the nature or the limited extension of their territory.

INCINERATIONINCINERATION is a possible, proven alternative but its dominating technology (the mass-burn grate combustion) has yet some drawbackshas yet some drawbacks, like low energy efficiencies, hazardous emissions and harmful final process residues.

Necessity of Alternatives to Necessity of Alternatives to Landfill and IncinerationLandfill and Incineration

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Italy

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Recycled Landfilled

Incinerated

NecessityNecessity of of More Sustainable Waste More Sustainable Waste Management TechniquesManagement Techniques

ECONOMICALLY AFFORDABLEECONOMICALLY AFFORDABLE

SOCIALLY ACCEPTABLESOCIALLY ACCEPTABLE

ENVIRONMENTALLY EFFECTIVEENVIRONMENTALLY EFFECTIVE

Economic SustainabilityEconomic Sustainability

GREATER GREATER VALUE RECOVERY FROM WASTEVALUE RECOVERY FROM WASTEgreater energy efficiencypotential polygeneration (energy and feedstock)valuable by-products

WIDER RANGE OF INVESTMENT ALTERNATIVESWIDER RANGE OF INVESTMENT ALTERNATIVESeconomical at smaller scaleat smaller scalepossibility to be optimised to specific waste streamspossibility to be optimised to specific waste streamspossible integration with Mechanical Biological Treatmentpossible integration with Mechanical Biological Treatment

FEEDSTOCK RECYCLINGFEEDSTOCK RECYCLINGvalue added products that can meet (even future) market

requirements

Social SustainabilitySocial Sustainability

NOT INCINERATION NOT INCINERATION (looking forward to reducingthe NIMBY effect)

LESS VISUAL IMPACT LESS VISUAL IMPACT (smaller chimney)

EASIER PLANT ACCEPTANCE BY THE EASIER PLANT ACCEPTANCE BY THE INTERESTED PEOPLEINTERESTED PEOPLE

Environmental SustainabilityEnvironmental SustainabilitySOLID SOLID WASTE AS A VALUABLE INDIGENEOUS WASTE AS A VALUABLE INDIGENEOUS

SOURCE OF FUELSOURCE OF FUELMSW and industrial wastes as a source of energy and

feedstockability to supplement fossil fuels in power generation and

other industrial processes

LESS SECONDARY WASTESLESS SECONDARY WASTESmore recyclable productsapproaching zero emissionzero emission process

GREATER GREATER SUSTAINABILITY ON THE WHOLE LIFE SUSTAINABILITY ON THE WHOLE LIFE CYCLECYCLE

improvement of LCA index for the main impact categories

Can Gasification and Pyrolysis Can Gasification and Pyrolysis Meet these Requirements?Meet these Requirements?Su

stain

ab

ility

Reduction

Incre

asi

ng

NIM

BY a

ttitu

des

Cost

Re-Use

Recycle

Disposal

Gasification/Pyrolysis

Material recycling

Energy recovery

Incineration

Gasification/Pyrolysisfor electricity

Gasification and Pyrolysis: Gasification and Pyrolysis: a Clear Distinctiona Clear Distinction

PYROLYSISPYROLYSIS is the the thermal process that implies the thermal process that implies the degradation of the organic materials at temperatures degradation of the organic materials at temperatures in the range 400in the range 400--800800°°C and in the absence of oxygen or C and in the absence of oxygen or other agents for chemical reactionother agents for chemical reaction .

GASIFICATIONGASIFICATION is the thermal process that involves the thermal process that involves the reaction of carbonaceous the reaction of carbonaceous feedstocksfeedstocks with oxygenwith oxygen--containing reagents, usually air, oxygen, steam or containing reagents, usually air, oxygen, steam or carbon dioxide, generally at temperatures in excess of carbon dioxide, generally at temperatures in excess of 800800°°CC .

Gasification and Pyrolysis: Gasification and Pyrolysis: a Clear Distinctiona Clear Distinction

PyrolysisPyrolysis

PYROLYSIS

HEATING VALUE OF GAS

30-40MJ/m3

LIQUID FEEDSTOCK

TO SYNTHESIS

GAS TURBINE

ENGINE

BOILER

SYNTHESIS

SOLIDS FILLER

ELECTRIC ENERGY

STEAM

PRODUCTS FOR

PETROCHEMICAL

INDUSTRY

Gasification Gasification

GASIFICATION

LHV GAS

4-6MJ/m3

MHV GAS

10-18MJ/m3 GAS TURBINE

SYNTHESIS

ENGINE

BOILER

SYNTHESIS

METHANOL

HYDROGEN

FUEL ALCOHOL

ELECTRICITY

PROCESS STEAM

AMMONIA

COMBUSTION FLUE GAS BOILER

CONVERSIONTECHNOLOGY

PROCESSING TECHNOLOGY

PRIMARY PRODUCTS

FINALPRODUCTS

STEAM &ELECTRICITY

Why gasification?Why gasification?


gasification offers both upstreamand downstream advantages.

All carbon-based materials, (e.g. biomass, wastes, pulper

sludge, natural gas) can be readily gasified after proper

preparation to produce synthesis gas for

subsequent production of energy and chemicals.

Gasification Gasification upup-- and downand down--stream flexibilitystream flexibility

gasification-based processes are the only advanced power generation technologies capable of producing the ultra-clean synthesis gas required for making multiple products.

The production of more than one product offers the unique opportunity to adjust to swings in market demand for products, while simultaneously maximizing the utilization of capital investment.


gasification produces an energy

carrier

Feedstock energy of the waste is transferred to

the syngas, rather than all converted into

thermal energy of flue gas. In this way it can be

stored and used when and where it is more

useful.


C + ½ O2 → CO -111 MJ/kmol CO + ½ O2 → CO2 -283 MJ/kmol

C + O2 → CO2 -394 MJ/kmol

By “investing” 28% of the heating value of carbon in the CO production, 72% of the carbon heating value is conserved in the gas. Since the fuel contains also some hydrogen, the percentage of the heat in the original fuel, which becomes available in the gas is, in modern processes, generally between 75 and 88%.

Were this value only 50% or lower, gasification would Were this value only 50% or lower, gasification would probably never have become such a commercially successful probably never have become such a commercially successful process. process.


gasification can reach high thermal efficiencies with competitive capital costs

On-going projects for power generation indicate that efficiencies between 45 and 50% will be reached within 2010 (with capital costs of about 800€/kWe) and between 50 and 60% within 2020 (with capital costs of about 700€/kWe).


gasification can be readily adapted with advanced technologies for the concentration of CO2 with limited impact on cost and thermal efficiency

The ability of a technology to achieve higher efficiencies and concentrate CO2 with minimal impact on the cost of final products will be major factors in technologies selection for future energy plants.


gasification provides a feasible and economical route to produce an H2-rich gas

that can then used as syngas for production of chemicals or hydrogen.


gasification is economically competitive with combustion for municipal and industrial waste management

having capital costs that, for the various proposed technologies, can range from 60 to 250€ per t/yinstalled (to be compared with a range 130-230 for incinerators) e gate fee that range between 30 and 100€ per t/y installed (to be compared with a range 40-60 for incinerators with capacity larger than 200.000t/y).


Waste type suitable for gasificationWaste type suitable for gasification

gasification helps conserve valuable water resources

since, for instance, it uses approximately 30-40% less water to produce electric power from coal, compared to other coal-based generation technologies.


gasification produces a fuel gas that is typically about 1/3 that from a conventional combustion plant

This possibility of processing lower volumes of gas translates to lower capital cost for pollution prevention.


gasification generates non hazardous solid residues

that can be readily used for landfill without added disposal costs or can be used in construction materials or further processed to produce value-added products. Together with the easy removal of S and N oxides, volatile Hg and other pollutants, this determines the real possibility to approach “a near-zero” levels of emissions when required.


Example of non hazardous solid residueExample of non hazardous solid residue

In the last decade, a number of novel anda number of novel and, in some cases, innovative technologies utilizing pyrolysis and innovative technologies utilizing pyrolysis and gasification processes have emergedgasification processes have emerged to address environmental issues and to improve the value of energy or materials outputs.

Such pyrolysis or gasificationSuch pyrolysis or gasification--based technologies can based technologies can work:work:

as standas stand--alone applications alone applications

as part of integrated or modular systems combining as part of integrated or modular systems combining pyrolysis, gasification and/or combustion processespyrolysis, gasification and/or combustion processes

Gasification & Pyrolysis: the Novel Gasification & Pyrolysis: the Novel Technologies for Solid Waste DisposalTechnologies for Solid Waste Disposal

PYROLYSIS is sometimes used as a PYROLYSIS is sometimes used as a preliminary separated stage prior to partial preliminary separated stage prior to partial oxidationoxidation or is coupled with a stage for or is coupled with a stage for combustion of the pyrolysis productscombustion of the pyrolysis products or is the or is the only process in a system where the pyrolysis only process in a system where the pyrolysis gas is used in a separate stage for energy and gas is used in a separate stage for energy and material recoverymaterial recovery..

Similar combinations can be found also for Similar combinations can be found also for GASIFICATION, which can follow a GASIFICATION, which can follow a pyrolysis stage, or can be coupled with a pyrolysis stage, or can be coupled with a combustion stage or can be the only process.combustion stage or can be the only process.

PyrolysisPyrolysis as a preliminary separated stage as a preliminary separated stage

prior to partial oxidationprior to partial oxidation

Compact PowerCompact Power

PKAPKA

TakumaTakuma

PyrolysisPyrolysis coupled with a stage for combustion of coupled with a stage for combustion of the the pyrolysispyrolysis productsproducts

VonVon RollRoll

BritishBritish PetroleumPetroleum

Fluidized Bed

Reactor

Mixed PlasticWastes

Nitrogen

Cyclone

Light hydrocarbons

Coke, sand, residual additives

Guard Bed

Lime

SolidResidues

Cyclones

Fines

VenturiLoop

SystemGas

FilterWax

Condenser

PyrolysisPyrolysis as the only process in a system where as the only process in a system where the the pyrolysispyrolysis gas is used in a separate stage for gas is used in a separate stage for energy and material recoveryenergy and material recovery

BCL/BCL/FercoFerco

Gasification can be coupled with a Gasification can be coupled with a combustion stagecombustion stage

EbaraEbara Twin Twin RecRec

FosterFoster WheelerWheeler

Gasification can be the only processGasification can be the only process

KruppKrupp UhdeUhde

Gasification technology suppliersGasification technology suppliers

Gasification Vs Incineration in JapanGasification Vs Incineration in Japan

Why fluidized beds?Why fluidized beds?


• The rapid and good mixing of solids leads to almost uniform isothermal conditions throughout the reactor, so allowing a reliable process control.

• The large thermal flywheel of well-mixed bed solidsresists to rapid temperature changes and avoids formation of cold or hot spots.

• The heat and mass transfer between gas and particles are high when comparing with those of other gas-solid reactors.

• The good quality of contact between gas and solids reactants increases their fractional conversions.


• The liquidlike flow of particles allows continuous controlled operations with easy handling

• The great operating flexibility makes possible to utilize different fluidizing agents, reactor temperatures and gas residence times, to add reagents along the reactor freeboard or riser and to operate with or without a specific catalyst.

• The absence of moving parts in the hot regions and the lower operating temperatures reduces maintenance times and costs

• The possibility to apply the process on a relatively small scale makes wider the range of investment alternatives

Process type Solid waste in input

Output Temperature range, °C

Commercial process

Low-temperature pyrolysis for feedstock recovery

Plastic wastes (polyolefins)

Gas (generally with a high content of aromatic and aliphatic hydrocarbons), oils, waxes

500-600 BP (BFB)

High-temperature pyrolysis for feedstock recovery

Mixed plastic wastes

High yield of gas (with high content of olefins or BTX-rich oil, depending on input waste and operating conditions)

600-900 Hamburg-ABB (BFB) Akzo (CFB)

Low-temperature gasification for energy production

ASR, WEEE, MSW

Energy 500-800 Ebara TwinRec (IRFB) Ebara ICFG

Pretreated MSW, RDF, MPW, ASR, biomass

Energy, syngas 800-1000 BCL/Ferco (CFB); Krupp Uhde (BFB); Foster Wheeler (CFB)

High-temperature gasification for (energy and) syngas production

Plastic wastes Syngas 1300-1500 EUP (BFB)

Fluidized Bed Gasification todayFluidized Bed Gasification today

Fluidized Bed Gasification todayFluidized Bed Gasification today

Gasification Pyrolisys Combustion

CFB IRBFB BFB

Energy Syngas Metals, glass ...

Grate Boiler

Von Roll

Foster Wheleer

Akzo

BCL Ferco FurnaceICFB

Ebara EUP

Ebara ICFG

Ebara TwinRec

Krupp

BP

BCL/BCL/FercoFerco

EbaraEbara Twin Twin RecRec

EbaraEbara Twin Twin RecRec: : AomoriAomori plantplant

EbaraEbara UbeUbe ProcessProcess

KruppKrupp UhdeUhde

Gasification/Pyrolysis todayGasification/Pyrolysis today

Research NeedsResearch Needs

FLUIDIZED BED FLUIDIZED BED GASIFICATION GASIFICATION ofofRDF and RDF and PACKAGING PACKAGING WASTESWASTES

The AMRA project The AMRA project

GASIFIER PARAMETERSGASIFIER PARAMETERS

geometricalgeometrical parametersparameters:: ID: 381mm; total height: 6m;wall tickness: 12.7mm

capacitycapacity:: 30-60kg/hfeedstocksfeedstocks:: RDF, biomass, mixed plastics, pulper

residuesgasificationgasification agentsagents:: air, steam, oxygen, nitrogen,

carbon dioxideoperatingoperating temperature:temperature: 700-950°Cflue gas treatments:flue gas treatments: cyclone, scrubber, flaresafety systems:safety systems: hydraulic guard, rupture disks, emergency nitrogen stream, safety valves, emergency bed material discharge, high- and low-pressure alarms



PROJECT GOALSPROJECT GOALSinvestigation on type and quality of products as a function of

operating conditionsinvestigation on gasification behavior of post-consumer

packaging wasteseffect of injection of different reactants along the freeboarddesign and operating criteria for in-bed and over-bed

feedingsafety aspects for medium-small plants improvement of knowledge about economics for companies

interested to operate in solid waste disposal

ConclusionsConclusions

Fluidized bed pyrolysis andFluidized bed pyrolysis and gasification may offer a real gasification may offer a real alternative to incinerationalternative to incineration, as it can be deduced by the novel treatment plants that are already operating for waste management. The reason can be found in: • greater flexibility to process specific wastesgreater flexibility to process specific wastes•• less secondary wastes and more recyclable productsless secondary wastes and more recyclable products•• greater energy efficiencygreater energy efficiency•• possibility to apply the process at smaller scalepossibility to apply the process at smaller scale•• possibility of material recycling to chemicalspossibility of material recycling to chemicals

ConclusionsConclusions

On the other hand, there is the disadvantage due to the the disadvantage due to the risk of a less proven technologyrisk of a less proven technology, particularly taking in mind the heterogeneous nature of feeds like MSW. Today the main technical challenges are related to obtain: • higher power production efficiencyhigher power production efficiency•• improved syngas cleaning improved syngas cleaning to meet defined specification•• ability to produce a vitrified slagability to produce a vitrified slagTherefore the economics are far away from clearthe economics are far away from clear, and only in the next future the market will indicate which technology has the most effective approach.

The last news about product flexibility The last news about product flexibility of BFB gasification and pyrolysis of BFB gasification and pyrolysis ……

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pyrolysis and gasification of solid wastes in … fluidization south africa fluidization into the...

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