Verenum Hochschule für Technik + Architektur Luzern
TITEL-FOLIE
Thomas Nussbaumer
Verenum Zürich, Switzerland www.verenum.ch
University of Lucerne, Technology and Architecture www.hta.fhz.ch
Cost of Particle Removal for 200 kW
to 2 MW Automatic Wood Combustion
by ESP and Fabric Filters
3rd IEA Workshop on „Aerosols from Biomass Combustion“
Jyväskylä (Finland), 3 September 2007
INHALT Kapitel 1
1. Introduction
2. Concept
3. Assumptions
4. Results
5. Conclusions
Verenum Hochschule für Technik + Architektur Luzern 0 10 20 30 40 50 60 70 80 90 100 >12.21 7.59 5.13 3.47 2.21 1.07 0.64 0.41 <0.41
Aerodynamischer Partikeldurchmesser [ Aerodynamic Diameter [µm]µm]
Ca
P M [m g /m n 3 ] (1 3 % O 2 )K
[Kaufmann & Nussbaumer 1998]
K, Ca, Na, Cl, S... ! KCl, K2SO4,CaCO3
INHALT Kapitel 1
1. Introduction
2. Concept
3. Assumptions
4. Results
5. Conclusions
Verenum Hochschule für Technik + Architektur Luzern
Hoval
nach [N. Klippel, 8th Int. Conf. on ESP, USA 2001 ] 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% 0.01 0.1 1 10 100 d [!m] A b s c h e id e g ra d 10.0 20.0 32.0 53.3 920 j [!A/m2 ] = SCA [s/m] : E [kV/cm ] = 2.67 Durchmesser D = 150 mm, Spannung U = 20 kV
Stromdichte j 920µA/m2 = Coronastrom 130 µA an Drahtlänge von 300 mm.
Increasing efficiency:
– Increasing residence time = increasing size – Increase of voltage
– Reduction of distance between electrodes
Separation efficiency of a tube ESP
Residence time Specific volume
– +
+
Particle precipitation
Raw gas Clean gas
Cyclone Electrostatic Precipitator (ESP) Fabric filter (FF)
Pre dedusting > 5!µm Fine particle removal < 10 ... < 0,01!µm
Condensation! C-content < 2%
Verenum Hochschule für Technik + Architektur Luzern
INHALT Kapitel 1
1. Introduction
2. Concept
3. Assumptions
4. Results
5. Conclusions
Method of Annuity
Heat production cost = Capital + Fuel + Operation cost
Capital cost = Annuity x Investment cost
Fuel cost = (Power / Efficiency) x Fuel price
Operation cost = f (Investment cost, fuel type)
respecting lifetime of filter of 5a, cost for power, press. Air, dp
Verenum Hochschule für Technik + Architektur Luzern
Basic Assumptions
Fuel Wood chips 3 Ct./kWh*
Light fuel oil 6 Ct./kWh (60 Ct./l)
Capital Interest rate 5% p.a. Calculation period 15 a / 30 a
Operation Full load hours 2000 h/a
PM after cyclone 200 mg/m3 @ 11 or 13% O
2
after precipitator < 20 mg/m3
Carbon content < 5% for ESP < 2% for FF *[CARMEN 2006]: 1.2 – 3 Ct./kWh
INHALT Kapitel 1
1. Introduction
2. Concept
3. Assumptions
4. Results
5. Conclusions
Verenum Hochschule für Technik + Architektur Luzern
Investment cost
0 100 200 300 400 500 600 700 800 0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2 Heat output [MW]Investment costs [1000 Euro]
Technique w/o building and w/o precipitation Building ESP Fabric filter Investment c o st [1000 Euro] Heat output [MW]
Specific investment cost (without building)
0 200 400 600 800 1000 1200 1400 1600 1800 0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2 Heat output [MW]
Specific investment costs w/o building [Euro/kW]
Plant with ESP Plant with fabric filter Plant w/o precipitation
Specific Investment c o st [ E u ro /k W ] w it h o u t b u ild in g Heat output [MW]
Verenum Hochschule für Technik + Architektur Luzern
Increase of investment cost by ESP/FF
0 5 10 15 20 25 30 35 40 45 0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2 Heat output [MW]
Increase of investment costs for technique
[% ] ESP Fabric filter Increase o f Total Investment Cost Heat output [MW] [%]
Increase of heat production by ESP
0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2 Heat output [MW] [Ct./kWh]
Total cost ESP Capital cost ESP Operating cost ESP
Cost for particle separation [Ct ./kWh] Heat output [MW]
Verenum Hochschule für Technik + Architektur Luzern 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2 Heat output [MW] [Ct./kWh]
Total cost fabric filter Capital cost fabric filter
Operating cost fabric filter
Increase of heat production by FF
Cost for particle separation [Ct ./kWh] Heat output [MW]
Heat production cost from wood and light fuel oil
20 mg/m3 OAPC 1.9.2007 in Switzerland 20 mg/m3 > 2008
Wood with ESP
Wood with fabric filter
Wood with cyclone only
Light fuel oil (CH)
Heat output [MW] Heat production cost [Ct ./kWh]
Fuel price Wood: 3 Ct./kWh
Light fuel oil: 6 Ct./kWh (" 60.–/100 l)
Capital cost 5% p.a. for 15 years Operation with 2000 h/a
+ 6% + 8% + 12% + 20% + 30% 50 mg/m3 > 2008
Verenum Hochschule für Technik + Architektur Luzern
INHALT Kapitel 1
1. Introduction
2. Concept
3. Assumptions
4. Results
5. Conclusions
Conclusions
1. Particle removal by ESP and FF is available and proven from 500 kW to 2 MW for a limit value of 20 mg/m3
– real emissions are typically < 5 ... 10 mg/m3 – and heat production cost increase by 6 – 12%
2. ESP exhibit higher investment cost, FF exhibit higher operation cost,
resulting in almost equal total cost - not considering higher requirements for fuel quality in case of FF
3. Applications from 100 kW are possible, however, specific cost of equipment on the market increase dramatically < 500 kW,
Verenum Hochschule für Technik + Architektur Luzern
Conclusions
4. To guarantee high removal efficiency in practice, strong
quality requirements are needed for combustion design and
control and for plant planning and operation:
– Availability > 97% needs:
- No On/Off and long stationary operation
- Heat exchange varying with load to enable T > 120°C – High burnout quality: 5% C for ESP, 2% C for FF
– Limited water content for FF
– Further experiences for < 1 MW needed
5. FF are more critical for carbon burnout, glowing particles and condensation.
ESP are advantageous for wet fuels or difficult conditions, while FF can easily be applied for dry fuels and optional sorptive removal of HCl, SO2, and PCDD/F.
INHALT Kapitel 1
Download: www.verenum.ch
Nussbaumer, Th.: Stand der Technik und Kosten der
Feinstaubabscheidung für automatische Holzfeuerungen von 100 kW bis 2 MW. Zürich 2006, ISBN 3-908705-13-4
