Effect of combustion air humidification on the operation of a biomass boiler – Theoretical analysis

The article describes the influence of additional installation of the combustion air humidifier for a biomass hot water boiler, which is equipped with a flue gas spray condenser, on its operating parameters and the heat supplied to the district heating system. Humidification of the air is carried ou...

Full description

Saved in:
Bibliographic Details
Main Authors: Tomáš Dlouhý, Jan Havlík
Format: Article
Language:English
Published: Elsevier 2025-02-01
Series:Heliyon
Subjects:
Online Access:http://www.sciencedirect.com/science/article/pii/S2405844025006796
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1832576429992181760
author Tomáš Dlouhý
Jan Havlík
author_facet Tomáš Dlouhý
Jan Havlík
author_sort Tomáš Dlouhý
collection DOAJ
description The article describes the influence of additional installation of the combustion air humidifier for a biomass hot water boiler, which is equipped with a flue gas spray condenser, on its operating parameters and the heat supplied to the district heating system. Humidification of the air is carried out by spraying with water heated in the flue gas condenser, which is pre-cooled in the exchanger for preheating the return water from the district heating system. The case of the additional installation of the combustion air humidifier to the biomass hot water boiler USTSEN type JUE-FVB 7.2 with a heat output of 8 MW equipped with flue gas spray condenser is analyzed. Humidification and preheating of the combustion air leads to fuel savings and an increase in the dew point temperature of the flue gas, which improves the conditions for utilizing the waste heat from the flue gas in the condenser, as the heat is available at a higher temperature level. Humidification of the combustion air also affects the operating parameters of the boiler. In particular, the flue gas outlet temperature and flow rate increase and the efficiency of the boiler decreases slightly. Fuel consumption, however, decreases due to the heat input in the preheated and humidified combustion air. The application of the proposed solution would increase the heat supplied to the district heating system, by about 7 %–9 % of the boiler nominal heat output, depending on the heating of the air in the humidifier. A summer drop in biomass moisture would be reflected in a reduction in the energy benefit of the flue gas condenser by more than 20 %. However, humidification of the combustion air can limit this negative effect.
format Article
id doaj-art-adb06d6cd60949158c96a7e39b800e8a
institution Kabale University
issn 2405-8440
language English
publishDate 2025-02-01
publisher Elsevier
record_format Article
series Heliyon
spelling doaj-art-adb06d6cd60949158c96a7e39b800e8a2025-01-31T05:12:06ZengElsevierHeliyon2405-84402025-02-01113e42299Effect of combustion air humidification on the operation of a biomass boiler – Theoretical analysisTomáš Dlouhý0Jan Havlík1Faculty of Mechanical Engineering, Czech Technical University in Prague, Prague, Czech RepublicCorresponding author. Faculty of Mechanical Engineering, Czech Technical University in Prague, Technicka 4, 16600, Prague, Czech Republic.; Faculty of Mechanical Engineering, Czech Technical University in Prague, Prague, Czech RepublicThe article describes the influence of additional installation of the combustion air humidifier for a biomass hot water boiler, which is equipped with a flue gas spray condenser, on its operating parameters and the heat supplied to the district heating system. Humidification of the air is carried out by spraying with water heated in the flue gas condenser, which is pre-cooled in the exchanger for preheating the return water from the district heating system. The case of the additional installation of the combustion air humidifier to the biomass hot water boiler USTSEN type JUE-FVB 7.2 with a heat output of 8 MW equipped with flue gas spray condenser is analyzed. Humidification and preheating of the combustion air leads to fuel savings and an increase in the dew point temperature of the flue gas, which improves the conditions for utilizing the waste heat from the flue gas in the condenser, as the heat is available at a higher temperature level. Humidification of the combustion air also affects the operating parameters of the boiler. In particular, the flue gas outlet temperature and flow rate increase and the efficiency of the boiler decreases slightly. Fuel consumption, however, decreases due to the heat input in the preheated and humidified combustion air. The application of the proposed solution would increase the heat supplied to the district heating system, by about 7 %–9 % of the boiler nominal heat output, depending on the heating of the air in the humidifier. A summer drop in biomass moisture would be reflected in a reduction in the energy benefit of the flue gas condenser by more than 20 %. However, humidification of the combustion air can limit this negative effect.http://www.sciencedirect.com/science/article/pii/S2405844025006796Combustion air humidifierBiomassBoiler efficiencyFlue gas condenserHeat recovery
spellingShingle Tomáš Dlouhý
Jan Havlík
Effect of combustion air humidification on the operation of a biomass boiler – Theoretical analysis
Heliyon
Combustion air humidifier
Biomass
Boiler efficiency
Flue gas condenser
Heat recovery
title Effect of combustion air humidification on the operation of a biomass boiler – Theoretical analysis
title_full Effect of combustion air humidification on the operation of a biomass boiler – Theoretical analysis
title_fullStr Effect of combustion air humidification on the operation of a biomass boiler – Theoretical analysis
title_full_unstemmed Effect of combustion air humidification on the operation of a biomass boiler – Theoretical analysis
title_short Effect of combustion air humidification on the operation of a biomass boiler – Theoretical analysis
title_sort effect of combustion air humidification on the operation of a biomass boiler theoretical analysis
topic Combustion air humidifier
Biomass
Boiler efficiency
Flue gas condenser
Heat recovery
url http://www.sciencedirect.com/science/article/pii/S2405844025006796
work_keys_str_mv AT tomasdlouhy effectofcombustionairhumidificationontheoperationofabiomassboilertheoreticalanalysis
AT janhavlik effectofcombustionairhumidificationontheoperationofabiomassboilertheoreticalanalysis