BIOMORPHIC CERAMICS MATERIALS FOR HIGH...
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BIOMORPHIC CERAMICS MATERIALS FOR HIGH TEMPERATURE AND PRESSURE INDUSTRIAL FILTRATION PROCESSES
Transcript of BIOMORPHIC CERAMICS MATERIALS FOR HIGH...
BIOMORPHIC CERAMICS MATERIALS FOR HIGH TEMPERATURE AND PRESSURE INDUSTRIAL
FILTRATION PROCESSES
Biofil gasification test project.
Biofil is a project leader by the Biomorphic and Multifunctional Materials group associated to the Condense Mater Physics Department from the University of Seville, joint to AICIA, INERCO, CIDEMCO and Biomorphic EBT. With financial support from the European Commission and theSpanish Ministry of the Environment.
The aim of this project is to develop and test a new generation of bio-inspired ceramic materials to industrial filtration processes at high temperatures and pressure.
A candle prototype made with porous bioSiC® and suitable for an experimental biomass gasification facility has been designed, produced and characterized by Biomorphic EBT in collaboration with the Condensed Mater Physics Department of the University of Seville.
ETSI-University of Seville gasification pilot plant
The porous bioSiC® candles will be tested in a large high temperature filtration facility at the ETSI-University of Seville. This pilot plant allows testing different filters and pulses cleaning strategies under an extensive range of operating conditions such as temperature and pressure.
Two experimental campaigns have been already carried out using real coal ash at high temperature and pressure. (up to 600 ºC and 7.5 bar respectively).
The first experimental campaign commenced in 2005; four types of commercial filters were tested at maximum temperature and pressure of 235 ºC and 7.5 bar respectively.
In a second stage, the experimental campaign was conducted with operating temperatures increased up to 370 ºC-600 ºC, three types of elements (one type of bag filter and two types of ceramic candles) were tested.
GAS CLEANING
SILICON CARBIDE CANDLE
DIRTY GAS
GAS CLEANING
CLEAN GAS
DIRTY GAS
CLEAN GAS
GAS CLEANING
SILICON CARBIDE CANDLE
DIRTY GAS
GAS CLEANING
CLEAN GAS
DIRTY GAS
CLEAN GAS
BioSiC®
Mechanical Properties at room Temperature
Density 1.1 a 2.6 g·cm-3
Young Modulus 25 a 250 GPa
Compressive strength 1500 Mpa
Bending strength 430 Mpa
Toughness 3 Mpa·m1/2
Dilatation coefficient 3.5·10-6
K-1
Thermal Properties
Anisotropic Thermal Conductivity (variation up to 30%).
Tailorable values in a wide range (50-120 W/mK).
Electrical Properties
Anisotropic Electrical Resistivity (ratio over 10). .
Tailorable values in a wide range (0.02-20 Ω·cm).
Adjustable dependence with temperature.
Biomorphic silicon carbide (bioSiC®) is an SiC-based advanced ceramic material, fabricated through a cost effective and environment friendly process that uses cellulose as its starting point.
BioSiC® shows excellent thermo-mechanical performance, chemical and structural stability, in a wide interval of temperatures. It’s possible to tailor the thermal and electrical properties of these materials to a wide range of values to satisfy device requirements.
BioSiC®
Advantages
Low processing temperatures.It’s no necessary start from high purity SiC whiskers or dust.It’s no necessary additive use. Synthesis rates increases significantly.Wide microstructure diversity and propertiesComplex shapes are reproducible.
Applications
High temperature heat exchangers.High temperature filters.Acoustic and thermal isolation.Low density and high strength for medical implantsResistant devices with electrical conductivityBallistic protection.Brake pads or high temperature seals.Concrete reinforcement for extreme environmental conditions Joint pieces for wood structuresFurnace furniture.
Precursors selectionBamboo Cork
Pine
Sapele
White Eucalypt
Holm Oak
Red Eucalypt
Beech
The precursor must be infiltrated completely: Porous microstructure had to be connected with a desirable size.Uniform microstructure at macroscopic scale.Porous size distribution had to ensure permeability during fabrication process
Artificial Wood
MDF HDF WPCDensity (g·cm-3) 0.5 to 0.8 0.6 to 1.5 0.9 to 1.2
Porous bioSiC®
Porous carbon from MDF wood (BioC)
BioSiC®
Remove Si from porous
Porous BioSiC®
Porous bioSiC®
Porous size distribution. (Mercury Porosimetry)Porous size
Cerámica y Vidrio CSIC Madrid
Etching time (h)
Pososity (%)
Porous size range (μm)
Peak porous size (μm)
Permeability range (Pressure range 2-4·106
dyn·cm-2
)
3 46.6 0.3-30 18 3-4·10-5
cm3·(s·dyn)-1
9 42.9 0.2-30 15 2-3.5·10-5
cm3·(s·dyn)-1
24 48.1 0.2-50 18 2.7-3.6·10-5
cm3·(s·dyn)-1
48 49.3 0.3-50 17 3-5·10-5
cm3·(s·dyn)-1
Porous bioSiC®
Stress-Strain curve
Porous bioSiC®
Micro-indentation Hardness (200g-500g load)bioSiC/Si–Sepele: 1400 HVbioSiCp-Sepele : 1650 HVbioSiC/Si-DM: 1000 HVbioSiCp-DM: 1600 HV
a) b)
Porous bioSiC®
Samples Average bending strength (MPa)
Porous bioSiC®
MDF 76.6CSi filter 13.5
2max 43bhFL
=σFour point bending
Porous bioSiC®
CandlesCandles have been tested after acid etching to ensure that Si enough has been remove, obtaining a desirable porosity
Filter test:
The pressure drop across the filtering elementThe cleaning pulse interval defined as the cleaning operation frequency or the period time between consecutive cleaning operations ( 400 to 1000 ms)The baseline pressure drop, which is the pressure drop immediately after cleaningFiltration efficiency of the elements
Authors:Julián Martinez-Fernandez, Faculty of Physics,
University of SevillaTel.: +34954559732; E-mail address:
Javier Quispe, Biomorphic-EBTTel.: +3495455907; E-mail address:
J. Vicente García Barbosa. Faculty of Physics, University of Sevilla
Tel.: +34954559543; E-mail address: [email protected]
