plasma assisted preparation of coal for combustion

PLASMA PLASMA ASSISTED PREPARATION OF COAL FOR COMBUSTIONASSISTED PREPARATION OF COAL FOR COMBUSTIONPLASMA PLASMA ASSISTED PREPARATION OF COAL FOR COMBUSTIONASSISTED PREPARATION OF COAL FOR COMBUSTIONV.E. Messerle, E.I. Karpenko,

Combustion problems Institute, Research Institute of Experimental and Theoretical Physics,

Experience of the practical application of plasmasummarized . Plasma -fuel systems (PFS) have beensummarized . Plasma -fuel systems (PFS) have beenPlasma activation of coal increases the coal reactivityPlasma activation of coal increases the coal reactivityecologically friendly incineration of low -rank coalcombustors of coal -fired thermal power plants in differentcombustors of coal -fired thermal power plants in differentsuccessfully on 29 pf boilers for steam productivitiesstart up and pf flame stabilisation .

THE TECHNOLOGY CONCEPTTHE TECHNOLOGY CONCEPT

start up and pf flame stabilisation .

In the framework of the technology concept


In the framework of the technology conceptfrom the main pf flow and undergone the activation

The mainSketch of the Plasma -Fuel System (PFS) -pf burner with the plasmatron .

PFS is

DC arc plasma

pf burner with the plasmatron .

DC arc plasma

with the

being formedbeing formed

blown

electrodes

electrodeselectrodes

not exceed

coulombcoulomb

plasmatron

from 100

1 – plasmatron ; 2 – primary air/coal mixture (stage 1); 3 – primary air/coal mixture (stage 2); 4 – secondary air; 5 – plasma flame; 6 –

INDUSTRIAL TESTSINDUSTRIAL TESTS

air/coal mixture (stage 2); 4 – secondary air; 5 – plasma flame; 6 –plasma activated pulverised coal flame; 7 – furnace.

PFS have been tested for boilers plasma start up and flame stabilization

testing power coals of all ranks (brown, bituminous, anthracite and


testing power coals of all ranks (brown, bituminous, anthracite and50%, ash—from 15

to 48% and calorific

values — from 6700 tovalues — from 6700 to

25,100 kJ/kg . The boilers

were fitted with differentwere fitted with different

systems of pf preparation

(such as the direct pf(such as the direct pf

injection and systems with

pf hopper). Total 73 PFS

were mounted and tested onwere mounted and tested on

the boilers . The main

summary of these tests issummary of these tests is

that the developed PFS

improve coal combustion

efficiency and decrease

Schematic view of the PFS arrangement on the furnac e of the boiler of 420

efficiency and decrease

harmful emission

from pulverised Schematic view of the PFS arrangement on the furnac e of the boiler of 420of the 4 PFS in action (top view)

4.0

from pulverised

coal-fired TPP.

Specific power3.5

4.0

Unb

urne

d C

arbo

n (

%)Specific power

consumption for3.0

Unb

urne

d C

arbo

n (

%)

plasmatron influence

onto reduction of 2.0

2.5

Unb

urne

d C

arbo

n (

%)

onto reduction of

unburned carbon at

plasma aided1.5

2.0

Unb

urne

d C

arbo

n (

%)

plasma aided

pulverised coal0.00 0.05 0.10 0.15 0.20

1.0

combustion .0.00 0.05 0.10 0.15 0.20

Specific Power Consumption (kWh/kg of coal)

ASSISTED PREPARATION OF COAL FOR COMBUSTIONASSISTED PREPARATION OF COAL FOR COMBUSTIONASSISTED PREPARATION OF COAL FOR COMBUSTIONASSISTED PREPARATION OF COAL FOR COMBUSTIONKarpenko, A.B. Ustimenko *

Institute of Experimental and Theoretical Physics, Almaty, Kazakhstan; *e-mail [email protected]

plasma aided pulverised coal combustion technology isbeen developed to improve coal combustion efficiency .been developed to improve coal combustion efficiency .

reactivity and provides more effective ignition andreactivity and provides more effective ignition andcoal . PFS have been incorporated into a range of

different countries . The technology has been testeddifferent countries . The technology has been testedproductivities ranging from 75 to 670 t/h for the boilers’ oil-free


concept some portion of pulverised solid fuel (pf) is separated


concept some portion of pulverised solid fuel (pf) is separatedactivation by arc plasma in a special chamber—PFS

main element of the

plasmatron . It is

plasma generatorplasma generator

the plasma gas

formed from airformed from air

through the Sketch of the DC plasmatron : 1 – anode; 2 – cathode; 3 – air; 4 – plasma flameelectrodes . The

electrodes erosion does

2 – cathode; 3 – air; 4 – plasma flame

electrodes erosion does

exceed 2*10-9 kg per

coulomb . Thecoulomb . The

plasmatron power varies

100 to 200 kW.

DC plasmatron in action


stabilization in different countries at 17 Thermal Power Plants (TPP). At PFS

their mixtures) were used . Volatile content of them varied from 4 to


their mixtures) were used . Volatile content of them varied from 4 to

Schematic view of the PFS arrangement on the furnac e of the boiler of 420 ton/h steam rate and photograph Schematic view of the PFS arrangement on the furnac e of the boiler of 420 ton/h steam rate and photograph of the 4 PFS in action (top view) .

500

Con

cent

ratio

n (

ppm

)

Specific power

Con

cent

ratio

n (

ppm

)

Specific power

consumption for

400

Con

cent

ratio

n (

ppm

)

plasmatron influence

onto reduction of

300

NO

X C

once

ntra

tion

(pp

m)

onto reduction of

nitrogen oxides

concentration at plasma

0.00 0.05 0.10 0.15 0.20

300concentration at plasma

aided pulverised coal0.00 0.05 0.10 0.15 0.20

Specific Power Consumption (kWh/kg of coal)combustion .

plasma assisted preparation of coal for combustion

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