Biomass Furnace PAES 242-243:2010 Flashcards
organic materials used as renewable source of energy like wood chips, corncobs and rice
hulls, etc.
biomass
enclosed structure for intense heating by fire using any biomass like woodchips, corncobs and
rice hulls as fuel
biomass furnace
fire resistant surface located at the heating chamber of the biomass furnace
hearth
materials to be processed (i.e. dried, burned, melted, etc.) using biomass furnace
workload
framework of metal bars or fire bricks used to hold biomass fuel in furnace for more efficient
combustion
grate
Flue gas and other products of combustion goes into the dryer.
Direct-fired biomass furnace
Biomass fuels are fed on the combustion chamber in cyclonic manner using a blower. The
biomass fuels in this type of furnace are burned while in suspension.
Cyclonic
Biomass furnace with combustion chamber that have stair-liked arrangement of grate
Step-grate
Biomass furnace that uses gravitational force on feeding the biomass fuel.
Gravity
This type of biomass furnace shall use a heat exchanger to prevent flue gas and other
products of combustion to go with the drying air.
Indirect-fired biomass furnace
Uses ambient air to be heated inside or outside the heat exchanger and be used as drying air.
Dry type biomass furnace
Uses hot fluid as medium of heat transfer
Wet type biomass furnace
Heat resisting lining of the furnace using layer/s of fire bricks
Brick lining
Heat resisting lining of the furnace using ceramic materials
Ceramic fiber lining
Heat resisting lining of the furnace using aggregates and bonding agent(s)
Monolithic lining
Consist of course and fine grains with suitable bonding cement. These are poured in place
using molds or pouring forms after mixing with water.
Castable refractory
Kind of castable refractory mortar with a consistency that makes it easy to trowel into place.
These are very useful for patching and for shaping complex surfaces.
Trowelable refractory
Contain a binder material, and are tempered with water so that they have suitable plasticity
for pounding or ramming into place.
Plastic refractory
Similar to that of plastic refractory but stiffer.
Ramming refractory
Tempered with water and/or with a binder added for softer plasticity and permits patching in
place.
Patching refractory
Have course and fine refractory grains and bonding agents, suitable for installation with a
gunning machine.
Gunning refractory
Can be injected in a slurry state into small places such as gaps and wide cracks, and for filling
molds with narrow passageways.
Injection refractory
Castable refractory materials that should be vibrated to fill all the voids in a mold.
Vibratable refractory
Form of a thin slurry that can be brushed onto or otherwise coated on the working surface of
other refractory.
Coating refractory
Finely ground refractory materials that, when tempered with water, become trowelable for
bonding layered-up refractory shapes.
Refractory mortars
Single layer heat resisting lining of the combustion chamber and walls shall be able to
withstand the operating temperature of at most ________.
760 °C (1400 °F).
Biomass furnace that is operating with higher temperature than 760 °C (1400 °F) shall
have a ____.
multi-layer wall of hearth.
Insulation shall be made of fireproof materials like ceramic fiber paper or ceramic
wool, _____ magnesia, rock wool and/or mineral wool. It shall be placed between wall
linings and steel frame of the biomass furnace
85%
Angle of Repose (Cornhub)
30°-36°
Angle of Repose (Ricehull)
35°-50°
Combustion chamber shall have a force draft blower and/or passages/opening for air
inlet to ensure the complete burning of biomass fuel. For rice hull furnace, this blower
or chimney shall be able to support combustion and sustain temperature of __________ to _____ avoid crystallization of silica and caking. (Nguyen, 1995)
700 °C to
750 °C
The center to center distance of the heat exchanger tubes installed shall be more than
_____ times the tubes outside diameter.
1.25
Heating system efficiency of the furnace shall be at least ____ for direct-fired and
_____
for indirect-fired
65%
50%
Burning efficiency of the biomass furnace shall be at least
____.
95%.
Furnace efficiency shall be at least ___
65%
ratio of the actual and the theoretical heating value of fuel, expressed in percent
burning efficiency
ratio of the heat transferred and heat available in biomass furnace, expressed in percent
furnace efficiency
heat absorbed by a unit mass of a material at its boiling point in order to convert the material
into a gas without temperature change
latent heat of vaporization
distance between the horizontal supporting plane surface and the horizontal plane touching
the uppermost part of the biomass furnace.
NOTE: All parts of the biomass furnace projecting upwards are contained between these two planes.
overall height
distance between the vertical planes at the right angles to the median plane of the biomass
furnace and touching its front and rear extremities.
NOTE: All parts of the biomass furnace, in particular, components projecting at the front and at the rear are
contained between these two planes. Where an adjustment of components is possible, it shall be set at minimum
length.
overall length
distance between the vertical planes parallel to the median plane of the machine, each plane
touching the outermost point of the biomass furnace on its respective side.
NOTE: All parts of the biomass furnace projecting side wards are contained between these two planes
overall width
heat absorbed or evolved by a substance during a change of temperature that is not
accompanied by a change of state
sensible heat
ratio of actual and theoretical heat supplied by the fuel to the furnace, expressed in percent
heating system efficiency
Moistute Content
Corn cobs ____ (maximum)
Rice hulls___ (maximum)
10%
7%
Moistute Content
Corn cobs ____ (maximum)
Rice hulls___ (maximum)
10%
7%
Test duration shall be _______ after steady state operation and needed
measurements (heated air temperature from blower, air flow rate from blower
and ambient air temperature) shall be obtained and recorded every ________
interval.
two hours
ten minutes
Three- _____ samples of biomass fuel shall be randomly collected to be analyzed in the
laboratory.
50 g
The samples shall be totally burned using electric furnace for _______
Temperature.
5 hours at 1000°C
