1 PLASMA ASSISTED GASIFICATION OF COAL FOR THERMAL POWER PLANTS APPLICATION Prof. E.I. Karpenko, Prof. V.E.Messerle, Dr. A.B.Ustimenko NTO Plasmotekhnica Ltd., Almaty, Kazakhstan Research Institute of Experimental and Theoretical Physics, Kazakh National University, Almaty, Kazakhstan “New Horizons in Gasification” The12th European Gasification Conference 10–13 March 2014, Rotterdam, The Netherlands
Welcome message from author
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
1
PLASMA ASSISTED GASIFICATION OF
COAL FOR THERMAL POWER
PLANTS APPLICATION
Prof. E.I. Karpenko, Prof. V.E.Messerle, Dr. A.B.Ustimenko
NTO Plasmotekhnica Ltd., Almaty, Kazakhstan Research Institute of Experimental and Theoretical Physics,
Kazakh National University, Almaty, Kazakhstan
“New Horizons in Gasification” The12th European Gasification Conference
10–13 March 2014, Rotterdam, The Netherlands
140.1%
26.9%
319.4%
415.8%
515.9%
61.9%
WORLD ENERGY RESOURCES
Problem
Conventional (fuel oil) start up of a pulverized coal boiler and pf flame stabilization
1 – coal, 2 –oil fuel, 3 – gas, 4 – nuclear power, 5 – waterpower, 6 – renewable. (Key World Energy Statistics)
Solution
Sketch of Plasma-Fuel System (PFS).
The technology is based on plasma thermo- chemical
preparation of coal for burning and allows substituting
of gas or fuel oil by coal.
4
Temperature of the plasma flame
can reach 4000-6000 K.
Thermochemical preparation of
coal to burning is realized in the
PFS for rich coal/air mixtures (0.4-
0.6 kg of coal per one kg of air).
Concentrations of gaseous and
solid components depend on the
process temperature.
BASIC PRINCIPLES OF THE PLASMA TECHNOLOGY
5
Products of the plasma activation of pulverized power coal
Gas Phase Composition (vol.%) AC,
kg/h CC,
kg/h H2 CO CH4 C6H6 CO2 H2O N2 O2
14.2 18.4 0.3 0.6 6.8 2.9 56.4 0.3 1123.2 816.0
Gas temperature (К) Solids Temperature (К) Velocity of the flow
(m/s)
1270 1270 189.4
BASIC PRINCIPLES OF THE PLASMA TECHNOLOGY
6
BASIC PRINCIPLES OF THE PLASMA TECHNOLOGY
Features of interaction of electric-arc plasma with air-fuel
mixture in plasma-fuel system for coal ignition
Coal particles of 50-
100 micron in plasma
undergo heat shock,
as a result they are
crushed into
fragments, each
fragment is of a size of
5-10 micron . It is a
result of intensive
yield of coal volatiles
(CO, CO2, H2, N2,
CH4, C6H6 etc.) and
accelerates the process
of fuel combustion 3-4
times
7
Plasmatron is the main element of the plasma-fuel system
Arc burns between a cathode and anode and ionizes plasma gas, blowing through
the arc. The plasmatron’s arc power varies from 100 to 250 kW. The plasmatron
has main dimensions: length 0.5 m, diameter 0.25 m. It’s weight is about 25 kg.
Plasmatron
8
PLASMATRON
9
Plasma torch in operation
PLASMA-FUEL SYSTEM
10
EXPERIMENTAL PFS OPERATION
Coal consumption through the PFS – 2000 kg/h
11
EXPERIMENTAL PFS OPERATION
Coal consumption through the PFS is 1000 kg/h,
heat power is 5 mW
12
13
Thermotechnical characteristics of coals.
Coal Type Ww, % Ad, % Vdaf, % Qwl, kJ/kg
Shale 40-50 75-80 48-50 3500-8500
Lignite 32-57 10-35 25-61 4600-9600
Brown 25-35 15-20 35-50 12500-16000
Bituminous 5-12 20-45 15-40 16500-21000
Anthracite 5-8 25-35 4-10 18000-26000
Mixture of coals 10.4 48.5 38.2 13150
Note on abbreviations: Ww is moisture on dry basis; Ad is ash
content on dry basis; Vdaf is volatilisation on dry basis; Qwl is low
calorific value on dry basis
Industrial trials
Variety of the pf boilers and burners contractions
Boilers’ furnaces equipped with PFS (top view), and PFSs
15
Scheme of the PFS arrangement on 640 t/h steam boiler:
Gusinoozersk TPP, Russia.
Industrial trials
16
Image of the pulverised coal flame initiated in the PFS
during boiler start up from cold condition
Duration of the PFS operation at the coal consumption rate 2 t/h
1 min 5 min
3 m 5 m
Industrial trials
17
Pulverised coal flame plasma stabilisation
in a furnace of industrial boiler
Industrial trials
18
420 t/h steam boiler
furnace equipping
with PFS
(Almaty TEC-2,
Kazakhstan) :
1 – main pulverized
coal burners,
2 – PFS.
million million
Numerical experiment
19
1 – channel of the external flow of pf, 2 – secondary air duct, 3 - inlet of pf external
flow, 4 – inlet of pf internal flow, 5 - plasmatron, 6 – chamber for pf flow turning, 7 –
chamber for plasma chemical preparation of fuel for combustion, 8 - chamber for
mixing and thermochemical preparation of fuel, 9 - furnace
Layout of two stage PFS for the boiler BKZ-420 of Almaty TEC-2
20
Parameter Value
Plasmatron power, kW 200
Air-coal mixture temperature, К 362
Consumption of coal through PFS or internal channel of
the burner, kg/h 6000
Рrimary air rate, kg/h 8955
PFS length, m 3.687
Pulverized coal composition, mas. %
Ash C H2 H2O CO CO2 CH4 C6H6
40.0 46.18 2.63 1.84 3.95 1.4 0.55 3.45
Initial parameters for PFS computation
Composition of gaseous phase, vol. % Ash,
kg/h
C,
kgh H2 CO CH4 C6H6 CO2 H2O N2 O2
1.05 7.75 0.3 0.77 15.6 3.55 70.84 0.15 1518 261
Gas temperature, К Solids temperature, К Flow velocity , m/s
1025 1025 48.2
Composition of highly reactive fuel at the PFS exit
21
Gas (1) and particles (2) temperature
(T) distribution along the PFS (X).
Gas components concentration (Ci)
distribution along the PFS (X).
0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5400
600
800
1000
1200
1400
1
2
T,
K
X, m
0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.50.01
0.1
1
10
100
CH4
C6H
6
O2
N2
CO2
H2
CO
H2O
X, m
Ci,
%
Numerical experiment
22
Conventional incineration of coal Plasma assisted incineration of coal
using three PFS
Temperature field in the plane of the central burners and the PFS
23
Variation of averaged СО2 concentration along height
of the 420 t/h steam boiler furnace
1 – Regime with PFS
2 – Conventional regime of coal incineration
24
View of pf flame from PFS in boiler’s window
in the first minutes of the start up
Industrial trials
• Russia – 1994 – 2011
• Kazakhstan – 1989 – 2011
• China – 1995 – 2011
• Mongolia – 1994 – 2000
• Korea – 1992 – 1993
• Serbia – 2000 – 2008
• Slovakia – 2000
• Ukraine – 1989 – 2000
States concerned
• Germany
• Italy
• USA
• India
• Turkey
Concurrence
NOx reduction
Unburned carbon
reduction
250 ppm
500 ppm
1 %
4 %
Conventional technology
Plasma technology
1. Fuel Oil Rate for Russian TPP
5.1 mln. t/year (cost is more than $ 2.5 billion)
0
2. Fuel Oil Rate for Kazakhstan TPP
~1 mln. t/year (cost is about $ 500 mln.)
0
3. Investments for TPP
100% 3-5%
4. Operating costs
100% 28-30%
5. Electric power consumption for TPP auxiliary
3-5% 0.5-1.0%
Conclusion
Related Documents
