Stirling-aided heat and power (10 kW) production from wood pellets and planning a miniature ESP for small scale combustion

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Stirling-aided heat and power (10 kW) production
from wood pellets and planning a miniature ESP
for small scale combustion

• Martti Aho
• Research director, Renewable energy programmes,
  University of Jyvaskyla
• Evaluation of the Energy Research In Finland 1999
  - 2005,
• 31.05.2006 in University of Jyväskylä

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Goal of research

• Demonstration of electricity production from wood
  pellets in 10 kWe size in minimum of 15
  efficiency (from fuel energy) without operational
  problems

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Stirling-aided power productionState of art

• Routine from natural gas Electricity can be
  produced with efficiency of about 25.
• Power production from solid biomass is in
  research stage because of ash related problems
• Experiments in very small scale (1 kWe) has been
  conducted in the U.S.
• Experiments in 37-75 MWe scale have been
  conducted by Technical University of Denmark
  (DTU) and Austrian research centres. No
  commercial products yet.

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Concept under development
Traditional pellet boiler
Water
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Example of CFD calculations Fuel power 60 kW
High landa (a) and fuel gas recirculation (b)
with equal mass flow of flue gas
?1,47, circ. 46 m 48 g/s
?2,03, circ. 0 m 48 g/s (?1,47, circ. 0, m
33 g/s)
sectert 558 oC
sectert 345 oC
Tf1245
Tf1173
Tf 1224 oC
Clever air jet direction
a
b1
b2
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Comb. air preheating flue gas recirculation
Stirling-engine 9-10 kWe
Pellet burner
Vertical Furnace, fuel power 80 kW max
Economisers Extract about 60 kW)
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Co-operation

• Technical Research centre of Finland
• Helsinki University of Technology
• Finnish industry (four companies)
• International co-operation planned in a submitted
  EU proposal (ERA-NET)

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Development of miniature electrostatic
precipitator (ESP) for small scale combustion

• Goal
• To develop a miniature ESP for small scale
  combustion (lt 200 kW thermal) capable to reduce
  particulate concentration in the flue gas by 80
• State of art
• High need in the markets
• No commercial devices available
• Prototype development in Austria, Norway and
  Switzerland since 2003
• Our version differs from those prototypes

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Examples of results obtained so farParticle
charging principle (TUT)

• Scheme of the collector (JYU)

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Co-operation

• Technical Research centre of Finland (VTT)
• Tampere University of Technology (TUT)
• Helsinki University of Technology (HUT)
• Finnish industry (three companies)
• A proposal has been submitted to extend this
  research (EU level)