Biomass
boilers
For
warm water
- BIO
Automated, pellet, wood chips,
- Farmer
Automated, pellet,wood chips,
wood logs, multifuel
- Automat
Self-loading, automated, pellet,
wood chips, multifuel
Steam boilers
- Low pressure steam (0,5bar) automated boilers
for biomass, pellet, wood chips, multifuel
Coal
boilers
- Automated brown coal boilers
For warm water or low pressure steam
Fuel
feeder systems
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The fuel spectrum for
the CARBOROBOT boilers |
The CARBOROBOT is a multifuel technique boiler with
a wide fuel spectrum, from the different quality biomass materials
to the fossile coal to .
Renewable biofuels (biomass)
use is usually in the form of combustible solids, either wood,
the biogenic portion of municipal solid waste or combustible field
crops. Field crops may be grown specifically for combustion or
may be used for other purposes, and the processed plant waste
then used for combustion.
Fossil fuel is a fuel formed from the remains
of organic materials. Fossil fuels include coal, oil, and
natural gas.
Major traded forms of solid biofuels
EN ISO 17225 part 1 is a very general standard that explains
how to classify the biomass to be used for energy purposes and
lists the major traded forms of solid biofuels, see table.
Fuel name
|
Boiler
|
Size
|
Common preparation method
|
Whole tree |
no
|
< 500mm
|
No preparation or delimbed |
Wood chips |
BIO / Farmer
|
5 -100mm
|
Cutting with sharp tools |
Hog fuel |
BIO / Farmer
|
Variable
|
Crushing with blunt tools |
Log wood/firewood |
no
|
100 -1000mm
|
Cutting with sharp tools |
Bark |
|
Variable
|
Can be shredded or unshredded
|
Bundle |
no
|
Variable
|
Lengthways oriented &
bound |
Fuel powder |
no
|
< 1mm
|
Milling |
Sawdust |
no
|
1-5mm
|
Cutting with sharp tools |
Shavings |
no
|
1-30mm
|
Planing with sharp tools
|
Briquettes |
Farmer
|
> 25mm
|
Mechanical
compression |
Pellets |
BIO / Farmer
|
< 25mm
|
Mechanical
compression |
Bales |
no
|
|
|
Small square |
no
|
0.1m 3
|
Compressed and bound
to squares |
Big square |
no
|
3,7m 3
|
Compressed and bound
to squares |
Round bales |
no
|
2,1m 3
|
Compressed and bound
to cylinders |
Chopped straw |
no
|
10 -200mm
|
Chopped during harvesting
or before combustion |
Grain or seed |
BIO / Farmer
|
Variable
|
No preparation or drying
except for process operations necessary for storage for cereal
grain |
Fruit stones or kernel |
BIO / Farmer
|
5 - 15mm
|
No preparation or pressing
and extraction by chemicals |
Fibre cake |
Farmer
|
Variable
|
Prepared from fibrous
waste by dewatering |
BIO = Classic, Automat, Steam type CARBOROBOT
boilers |
|
Wood pellet, Agripellet
|
|
|
The pellet is biomass renewable material. The term
pelletting means the compressing of agricultural and forestry
materials. Pellets are compressed products manufactured on circular
cell roller presses, ranging from 6 to 25 millimetres in size.
More condensed pellets used for heating range from 6 and 12 millimetres
in size.
|
|
Further informations
Pellet |
|
Wood chips
|
|
|
Wood chip fuel is increasingly seen as an important
element in reducing our CO2 emissions. Wood provides the greatest
amount of renewable energy across Europe, though this is over
looked as most is used in small heating projects. The wood chip
good for the fuel mixing.
|
|
Further informations
Wood chip |
|
Firewood
|
|
|
Wood is now recognised as good value, at least as
cost effective as other renewables. The traditional form of wood
fuel which can be easily stored, air dried and burnt in a wide
range of appliances from open fires to modern automated boilers.
|
|
Further informations
Wood |
|
Corn, grain
|
|
|
The corn and many other grains, too: wheat, rice,
sorghums, millets, oats, rye, barley, rye, triticale, buckwheat,
fonio, cherry pits, olive pits and grains is what fuels our stoves.
Fuel mixing
|
|
Further informations
Corn & grain |
|
Fuel mixing (Co-firing)
|
|
|
The fuel mixing is the most important use direction
of CARBOROBOT boilers. This special designed boilers are able
to burn mixes of different biomass and fossile fuels. multi-fuel
combustion.
|
|
Further informations
Fuel mixing |
|
Residues & waste
|
|
|
Agricultural crop residues and waste are the plant
parts, primarily stalks and leaves, not removed from the fields
with the primary food or fiber product. Examples include corn
stover (stalks, leaves, husks, and cobs); wheat straw; and rice
straw. . Fuel mixing
|
|
Further informations
Residues & waste |
|
Coal
|
|
|
Coal is fossil fuel. Coal is classified as a nonrenewable
energy source because it takes millions of years to form. Coal
is cheap and high energy dense fuel. In CARBOROBOT may use alone
or ideal carrier for the biomass co-firing
in mixes. The coal industry has found several ways to reduce sulfur,
nitrogen oxides, and other impurities from coal. They have found
more effective ways of cleaning coal before it leaves the mine,
and coal companies look for low-sulfur coal to mne.
|
|
Further informations
Coal |
|
The ash melting
|
|
|
Straw contain potassium and sodium compounds. These
alkali compounds are present in all annual crops and crop residues
in particular. During combustion, alkali combines with silica
and causes slagging and fouling problems in conventional combustion
equipment designed for burning wood at higher temperatures. Volatile
alkali also lowers the fusion temperature of ash: in conventional
combustion equipment having furnace gas exit temperatures above
800°C, combustion of agricultural residue causes slagging.
|
|
Further informations
Ash |
|
Fuel
characteristics and autonomy of the boiler |
|
|
Conversion
factors |
|
|
This is a quick-reference list of conversion factors
used by the BIOenergy Feedstock Development Programs at ORNL. It
was compiled from a wide range of sources, and is designed to be
concise and convenient rather than all-inclusive. Most conversion
factors and data are given to only 3 significant figures. Users
are encouraged to consult other original sources for independent
verification of these numbers. The following are links to Web sites
we have found useful (many universities worldwide maintain good
guid+es and conversion calculator pages):
Energy contents are expressed
here as Lower Heating Value (LHV) unless otherwise stated (this
is closest to the actual energy yield in most cases). Higher Heating
Value (HHV, including condensation of combustion products) is greater
by between 5% (in the case of coal) and 10% (for natural gas), depending
mainly on the hydrogen content of the fuel. For most biomass feedstocks
this difference appears to be 6-7%. The appropriateness of using
LHV or HHV when comparing fuels, calculating thermal efficiencies,
etc. really depends upon the application. For stationary combustion
where exhaust gases are cooled before discharging (e.g. power stations),
HHV is more appropriate. Where no attempt is made to extract useful
work from hot exhaust gases (e.g. motor vehicles), the LHV is more
suitable. In practice, many European publications report LHV, whereas
North American publications use HHV.
Energy units
Quantities
- 1.0
joule (J) = one Newton applied over a distance of one meter (=
1 kg m2/s2).
- 1.0
joule = 0.239 calories (cal)
- 1.0
calorie = 4.187 J
- 1.0
gigajoule (GJ) = 109 joules = 0.948 million Btu = 239
million calories = 278 kWh
- 1.0
British thermal unit (Btu) = 1055 joules (1.055 kJ)
- 1.0
Quad = One quadrillion Btu (1015 Btu) = 1.055 exajoules
(EJ), or approximately 172 million barrels of oil equivalent (boe)
- 1000 Btu/lb = 2.33 gigajoules per tonne (GJ/t)
- 1000
Btu/US gallon = 0.279 megajoules per liter (MJ/l)
Power
- 1.0
watt = 1.0 joule/second = 3.413 Btu/hr
- 1.0
kilowatt (kW) = 3413 Btu/hr = 1.341 horsepower
- 1.0
kilowatt-hour (kWh) = 3.6 MJ = 3413 Btu
- 1.0
horsepower (hp) = 550 foot-pounds per second = 2545 Btu per hour
= 745.7 watts = 0.746 kW
Energy Costs
- $1.00
per million Btu = $0.948/GJ
- $1.00/GJ
= $1.055 per million Btu
Some common units of measure
- 1.0
U.S. ton (short ton) = 2000 pounds
- 1.0
imperial ton (long ton or shipping ton) = 2240 pounds
- 1.0 metric tonne (tonne) = 1000 kilograms
= 2205 pounds
- 1.0
US gallon = 3.79 liter = 0.833 Imperial gallon
- 1.0
imperial gallon = 4.55 liter = 1.20 US gallon
- 1.0
liter = 0.264 US gallon = 0.220 imperial gallon
- 1.0
US bushel = 0.0352 m3 = 0.97 UK bushel = 56 lb, 25
kg (corn or sorghum) = 60 lb, 27 kg (wheat or soybeans) = 40 lb,
18 kg (barley)
Areas and crop yields
- 1.0
hectare = 10,000 m2 (an area 100 m x 100 m, or 328
x 328 ft) = 2.47 acres
- 1.0
km2 = 100 hectares = 247 acres
- 1.0
acre = 0.405 hectares
- 1.0
US ton/acre = 2.24 t/ha
- 1
metric tonne/hectare = 0.446 ton/acre
- 100
g/m2 = 1.0 tonne/hectare = 892 lb/acre
- for
example, a "target" bioenergy crop yield might be:
5.0 US tons/acre (10,000 lb/acre) = 11.2 tonnes/hectare (1120
g/m2)
Biomass energy
- Cord: a stack of wood comprising
128 cubic feet (3.62 m3); standard dimensions are 4
x 4 x 8 feet, including air space and bark. One cord contains
approx. 1.2 U.S. tons (oven-dry) = 2400 pounds = 1089 kg
- 1.0
metric tonne wood = 1.4 cubic meters (solid
wood, not stacked)
- Energy
content of wood fuel (HHV, bone dry) = 18-22
GJ/t (7,600-9,600 Btu/lb)
- Energy
content of wood fuel (air dry, 20% moisture)
= about 15 GJ/t (6,400 Btu/lb)
- Energy
content of agricultural residues (range due to
moisture content) = 10-17 GJ/t (4,300-7,300 Btu/lb)
- Metric
tonne charcoal = 30 GJ (= 12,800 Btu/lb) (but
usually derived from 6-12 t air-dry wood, i.e. 90-180 GJ original
energy content)
- Metric
tonne ethanol = 7.94 petroleum barrels = 1262
liters
- ethanol
energy content (LHV) = 11,500 Btu/lb = 75,700 Btu/gallon = 26.7
GJ/t = 21.1 MJ/liter. HHV for ethanol = 84,000 Btu/gallon =
89 MJ/gallon = 23.4 MJ/liter
- ethanol
density (average) = 0.79 g/ml ( = metric tonnes/m3)
- Metric tonne biodiesel =
37.8 GJ (33.3 - 35.7 MJ/liter)
- biodiesel
density (average) = 0.88 g/ml ( = metric tonnes/m3)
Fossil fuels
- Barrel of oil equivalent (boe)
= approx. 6.1 GJ (5.8 million Btu), equivalent to 1,700 kWh. "Petroleum
barrel" is a liquid measure equal to 42 U.S. gallons (35
Imperial gallons or 159 liters); about 7.2 barrels oil are equivalent
to one tonne of oil (metric) = 42-45 GJ.
- Gasoline: US gallon = 115,000
Btu = 121 MJ = 32 MJ/liter (LHV). HHV = 125,000 Btu/gallon = 132
MJ/gallon = 35 MJ/liter
- Metric tonne gasoline = 8.53 barrels = 1356
liter = 43.5 GJ/t (LHV); 47.3 GJ/t (HHV)
- gasoline
density (average) = 0.73 g/ml ( = metric tonnes/m3)
- Petro-diesel = 130,500 Btu/gallon (36.4 MJ/liter
or 42.8 GJ/t)
- petro-diesel density (average) = 0.84 g/ml
( = metric tonnes/m3)
- Note
that the energy content (heating value) of petroleum products
per unit mass is fairly constant, but their density differs significantly
– hence the energy content of a liter, gallon, etc. varies between
gasoline, diesel, kerosene.
- Metric
tonne coal = 27-30 GJ (bituminous/anthracite);
15-19 GJ (lignite/sub-bituminous) (the above ranges are equivalent
to 11,500-13,000 Btu/lb and 6,500-8,200 Btu/lb).
- Note
that the energy content (heating value) per unit mass varies
greatly between different "ranks" of coal. "Typical"
coal (rank not specified) usually means bituminous coal, the
most common fuel for power plants (27 GJ/t).
- Natural gas: HHV = 1027 Btu/ft3
= 38.3 MJ/m3; LHV = 930 Btu/ft3 = 34.6 MJ/m3
- Therm
(used for natural gas, methane) = 100,000 Btu (= 105.5 MJ)
Carbon content of fossil fuels and bioenergy feedstocks
- coal (average) = 25.4 metric
tonnes carbon per terajoule (TJ)
- 1.0
metric tonne coal = 746 kg carbon
- oil (average) = 19.9 metric
tonnes carbon / TJ
- 1.0
US gallon gasoline (0.833 Imperial gallon, 3.79
liter) = 2.42 kg carbon
- 1.0
US gallon diesel/fuel oil (0.833 Imperial gallon,
3.79 liter) = 2.77 kg carbon
- natural gas (methane) = 14.4
metric tonnes carbon / TJ
- 1.0
cubic meter natural gas (methane) = 0.49 kg carbon
- carbon
content of bioenergy feedstocks: approx. 50%
for woody crops or wood waste; approx. 45% for graminaceous (grass)
crops or agricultural residue
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