Modelling of Technological Solutions to 4th Generation DH Systems

Abstract Flue gas evaporation and condensing processes are investigated in a direct contact heat exchanger - condensing unit, which is installed after a furnace. By using equations describing processes of heat and mass transfer, as well as correlation coherences for determining wet gas parameters, a model is formed to create a no-filling, direct contact heat exchanger. Results of heating equipment modelling and experimental research on the gas condensing unit show, that the capacity of the heat exchanger increases, when return temperature of the district heating network decreases. In order to explain these alterations in capacity, the character of the changes in water vapour partial pressure, in the propelling force of mass transfer, in gas and water temperatures and in the determining parameters of heat transfer are used in this article. The positive impact on the direct contact heat exchanger by the decreased district heating (DH) network return temperature shows that introduction of the 4th generation DH system increases the energy efficiency of the heat exchanger. In order to make an assessment, the methodology suggested in the paper can be used in each particular situation.

[1]  Jie Zheng,et al.  Heat recovery potentials and technologies in industrial zones , 2017 .

[2]  Kiari Goni Boulama,et al.  Heat and mass transfer between gas and liquid streams in direct contact , 2004 .

[3]  Masahiro Osakabe,et al.  Latent heat recovery from actual flue gas , 2002 .

[4]  Masahiro Osakabe,et al.  Condensation heat transfer on tubes in actual flue gas , 2001 .

[5]  T. A. Butcher,et al.  Condensing economizers for small coal-fired equipment , 1994 .

[6]  Dagnija Blumberga,et al.  Experimental Research of Flue Gas Condensing Unit , 2012 .

[7]  J. L. Bravo,et al.  Energy Recovery By Direct Contact Gas-Liquid Heat Exchange , 1988 .

[8]  A. Couvert,et al.  Mass transfer and deodorization efficiency in a countercurrent spray tower for low superficial gas velocities , 2009 .

[9]  Sven Werner,et al.  Achieving low return temperatures from district heating substations , 2014 .

[10]  T. Mahmud,et al.  Enhancement of Mass Transfer in a Spray Tower Using Swirling Gas Flow , 2006 .

[11]  Justin Michael Hill,et al.  Study of low-grade waste heat recovery and energy transportation systems in industrial applications , 2011 .

[12]  Jun-de Li,et al.  Condensation of vapor in the presence of non-condensable gas in condensers , 2011 .

[13]  Waldir Antonio Bizzo,et al.  Experimental study of the SO2 removal efficiency and volumetric mass transfer coefficients in a pilot-scale multi-nozzle spray tower , 2013 .

[14]  M. I. Shilyaev,et al.  Modeling of Heat and Mass Transfer and Absorption- Condensation Dust and Gas Cleaning in Jet Scrubbers , 2013 .

[15]  Amir Rahimi,et al.  A Simple One-Dimensional Model for Investigation of Heat and Mass Transfer Effects on Removal Efficiency of Particulate Matters in a Venturi Scrubber , 2009 .

[16]  Kwangkook Jeong,et al.  Theoretical prediction of sulfuric acid condensation rates in boiler flue gas , 2012 .

[17]  Dagnija Blumberga,et al.  Efficiency Diagram for District Heating System with Gas Condensing Unit , 2015 .

[18]  K. Comakli,et al.  Economic and environmental comparison of natural gas fired conventional and condensing combi boilers , 2008 .

[19]  Kwangkook Jeong,et al.  Recovery of Water from Boiler Flue Gas , 2008 .

[20]  Kwangkook Jeong,et al.  Analytical modeling of water condensation in condensing heat exchanger , 2010 .

[21]  T. A. Butcher.  CONDENSING ECONOMIZERS FOR SMALL COAL-FIRED BOILERS AND FURNACES PROJECT REPORT - JANUARY 1994 , 1994 .

[22]  Daniel David Hazell,et al.  Modeling and Optimization of Condensing Heat Exchangers for Cooling Boiler Flue Gas , 2011 .

[23]  Mahmoud Mohamed Ali,et al.  Development and Validation for RP-HPLC Method of Assay of Omeprazole Capsules Formulation , 2018 .

[24]  Masahiro Osakabe,et al.  Latent heat recovery from oxygen-combustion flue gas , 2000, Collection of Technical Papers. 35th Intersociety Energy Conversion Engineering Conference and Exhibit (IECEC) (Cat. No.00CH37022).

[25]  Xiaohui Zhang,et al.  Condensing boiler applications in the process industry , 2012 .

[26]  Ari Auvinen,et al.  Reduction of fine particle emissions from wood combustion with optimized condensing heat exchangers. , 2009, Environmental science & technology.

[27]  Meryem Terhan,et al.  Design and economic analysis of a flue gas condenser to recover latent heat from exhaust flue gas , 2016 .

[28]  Vadim Mizonov,et al.  A Cell Model to Describe and Optimize Heat and Mass Transfer in Contact Heat Exchangers , 2011 .

[29]  Yi Li,et al.  Direct contact condensation in packed beds , 2006 .