Share

Comparison of two absorption processes of absorption heat pump used in district heating systems: falling-film absorption.

Number: pap. n. 65

Author(s) : LI J., XIE X., JIANG Y.

Summary

Absorption heat pump is the key component of novel district heating systems based on absorption cycles. In this system, the absorption heat exchanger in heating stations is a kind of absorption heat pump which has a vertical multistage structure. This paper mainly discusses the heat and mass transfer form and the structure of absorber. The LiBr solution needs to be cooled before entering into absorber because of the large temperature difference between generator and evaporator. Also the solution usually needs to be cooled between different stages. Thus a new kind of absorption process is proposed, which is different from the traditional falling-film absorption. In this kind of absorption process, the LiBr solution is sprayed into columns for absorbing steam in the absorption space, and is only cooled outside the absorber and between neighboring stages. A simplified mathematical model for this kind of absorption was developed to predict the performance of heat and mass transfer process. The simulation results for temperature distribution and mass transfer performance are presented. The spraying absorption process and the ordinary falling film absorption process are compared using the simplified mathematics models to see whether the new kind one can save heat and mass transfer area and volume of the absorption heat exchanger. The comparison is based on real working conditions of district heating systems. The performance of the spraying column absorption process was also experimentally investigated in an absorption experimental unit on a vacuum experimental platform. The mass transfer coefficient in some cases is obtained by analysis of experimental results. The experimental results and coefficients can be used in the mathematical model and direct us to design the absorption heat pump.

Available documents

Format PDF

Pages: 9 p.

Available

  • Public price

    20 €

  • Member price*

    15 €

* Best rate depending on membership category (see the detailed benefits of individual and corporate memberships).

Details

  • Original title: Comparison of two absorption processes of absorption heat pump used in district heating systems: falling-film absorption.
  • Record ID : 30014357
  • Languages: English
  • Source: International sorption heat pump conference (ISHPC2014), College Park, United States, March 31-April 2, 2014.
  • Publication date: 2014/03/02

Links


See other articles from the proceedings (125)
See the conference proceedings

Indexing