Small Wood fired Appliances:

Emission Reduction by combined Methods1 2 I.Hartmann , V. Schmatloch

1 Deutsches Biomasse Forschungszentrum gGmbH, D - 04347 Leipzig 2 Spartherm Feuerungstechnik GmbH, D - 49324 Melle

Small wood fired appliances: Common names: wood stoves, tiled stoves, fireplaces

Standardisation: room heaters, inset appliances,

inserts

Intended use: living room heating and decoration

Typical features: manually fed with batches of cord wood, natural chimney draught, manually controlled by user, operation without electric power

AcknowldegementsThe project was funded by PTJ and the German Bundesministerium für Umwelt (BMU), FKZ 03KB051

Background: Small wood fired appliances such as stoves or fireplaces

are known to contribute significantly to the PM10

concentration in ambient air of many industrialized

countries. Due to the manual operation of these

appliances, user behaviour has an important effect on

their combustion performance. Therefore technical

improvements aim at both, technical optimisation of the

combustion technology and reduction of the user

influence. In this study a standard fireplace insert was

equipped with an automatic combustion air control, that

avoids user errors regarding the air setting, an

electrostatic precipitator for reduction of particle

emissions and a catalyst for improvement of gaseous

emissions.

Project: Period: 2011 to 2014, Field tests from 2012 to 2014

Laboratory tests: unmodified appliance as reference

Field tests: optimisation and testing of different configurations, validation of final setupgas analyser Eheim VISIT 02S, Sick Maihak Sidor, particle mass by HF according to VDI 2066, particle number TSI CPC 3781

Emission reduction compared to reference:

CO ~70%, particulates ~80%

above: setup for final field tests:

fireplace insert with ESP, catalyst

and automatic air control

left: CO emission of original

fireplace insert (lab reference)

compared to field test result with

ESP on/off and with/without catalyst

right: CO emission of original

fireplace insert (lab reference)

compared to field test result with

ESP on/off and with/without catalyst

below right: typical during field test

run showing flue gas temperature

(green), oxygen concentration

(blue), CO concentration (red) and

particle number concentration

(black) for one combustion cycle

with HV of ESP off and one cycle

with HV on.

ConclusionA conventional fireplace insert has been equipped

with a catalyst, an electrostatic precipitator and a

conventional automatic combustion air control.

For this combination fitness for use has been

demonstrated for an extended period of field tests

under realistic operation conditions in the field. A

significant reduction of CO and particle emissions

has been demonstrated by field tests.

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Deutsches Biomasseforschungsentrumgemeinnützige GmbH

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