TY - BOOK
T1 - Artificial dewatering of peat. Part 6. Peat production methods for the mechanical dewatering process
AU - Luukkainen, Veli-Matti
PY - 1993
Y1 - 1993
N2 - Alternative peat production methods based on so called
artificial (mechanical) dewatering have been studied in
several countries for many decades. In Finland, a
research program called the Artificial Dewatering of Peat
(ADEWA) was carried out at the Technical Research Centre
of Finland (VTT) during 1988 1992. Several techniques
for wet peat mining were tested at the Combustion and
Thermal Engineering Laboratory of VTT.
In the ADEWA research program, a new peat production
method, SLURRY COMP, was developed. The method is based,
in its optimum form, on a modified ridge transporting
method (Peco), on slurrying of milled peat from a
stockpile ridge, pumping of the slurry through pipelines
to the power plant, and, after chemical pretreatment,
dewatering by pressing.
Feasibility studies on wet milled peat and slurry
production as well as pilot scale pumping tests of peat
slurries have been carried out on the bog and under
laboratory conditions. In these studies, slurrying of
peat and pumping of that slurry have been established as
the most viable method for production of raw material for
the dewatering process.
In the rheological studies, the DS contents of the
slurries have been 4 7 % on the bog and 5 10 % in the
laboratory. According to the pressure losses measured in
the pipes of different sizes (inner diameters 140 400
mm), the optimal DS content of the slurry is about 7 8
% with the most common peats in Northern Finland, i.e.
Carex (sedge) peat. The mining and slurrying technique
(determining the particle size), peat type, pipe
diameter, and flow velocity have a great influence on the
flowing properties and pressure losses of peat slurry.
Based on our present knowledge, the SLURRY COMP method
produces fuel from sedge peat in Northern Finland at
almost the same cost as the normal milling (HAKU)
method. The production costs are about 48 53 mk/MWh and
44 50 mk/MWh with an annual production of 100 000 and
400 000 tons of dry solids. These amounts of dry peat
meet the fuel requirements of the power plants with an
electric output of 40 50 MW and 150 200 MW,
respectively. The peat thus produced has a dry solids
content of 35 %, which is adequate for the fuel used with
pressurized combustion techniques.
AB - Alternative peat production methods based on so called
artificial (mechanical) dewatering have been studied in
several countries for many decades. In Finland, a
research program called the Artificial Dewatering of Peat
(ADEWA) was carried out at the Technical Research Centre
of Finland (VTT) during 1988 1992. Several techniques
for wet peat mining were tested at the Combustion and
Thermal Engineering Laboratory of VTT.
In the ADEWA research program, a new peat production
method, SLURRY COMP, was developed. The method is based,
in its optimum form, on a modified ridge transporting
method (Peco), on slurrying of milled peat from a
stockpile ridge, pumping of the slurry through pipelines
to the power plant, and, after chemical pretreatment,
dewatering by pressing.
Feasibility studies on wet milled peat and slurry
production as well as pilot scale pumping tests of peat
slurries have been carried out on the bog and under
laboratory conditions. In these studies, slurrying of
peat and pumping of that slurry have been established as
the most viable method for production of raw material for
the dewatering process.
In the rheological studies, the DS contents of the
slurries have been 4 7 % on the bog and 5 10 % in the
laboratory. According to the pressure losses measured in
the pipes of different sizes (inner diameters 140 400
mm), the optimal DS content of the slurry is about 7 8
% with the most common peats in Northern Finland, i.e.
Carex (sedge) peat. The mining and slurrying technique
(determining the particle size), peat type, pipe
diameter, and flow velocity have a great influence on the
flowing properties and pressure losses of peat slurry.
Based on our present knowledge, the SLURRY COMP method
produces fuel from sedge peat in Northern Finland at
almost the same cost as the normal milling (HAKU)
method. The production costs are about 48 53 mk/MWh and
44 50 mk/MWh with an annual production of 100 000 and
400 000 tons of dry solids. These amounts of dry peat
meet the fuel requirements of the power plants with an
electric output of 40 50 MW and 150 200 MW,
respectively. The peat thus produced has a dry solids
content of 35 %, which is adequate for the fuel used with
pressurized combustion techniques.
KW - peat
KW - mining
KW - slurries
KW - transportation
KW - hydraulic transport
KW - pumping
KW - rheology
KW - costs
M3 - Report
SN - 951-38-4460-9
T3 - VTT Tiedotteita - Meddelanden - Research Notes
BT - Artificial dewatering of peat. Part 6. Peat production methods for the mechanical dewatering process
PB - VTT Technical Research Centre of Finland
CY - Espoo
ER -