Energetic, environmental and economic analysis of drying municipal sewage sludge with a modified sustainable solar drying system


Khanlari A., Tuncer A. D. , SÖZEN A., Sirin C., GÜNGÖR A.

SOLAR ENERGY, vol.208, pp.787-799, 2020 (Peer-Reviewed Journal) identifier identifier

  • Publication Type: Article / Article
  • Volume: 208
  • Publication Date: 2020
  • Doi Number: 10.1016/j.solener.2020.08.039
  • Journal Name: SOLAR ENERGY
  • Journal Indexes: Science Citation Index Expanded, Scopus, Academic Search Premier, PASCAL, Aerospace Database, Agricultural & Environmental Science Database, Applied Science & Technology Source, Communication Abstracts, Compendex, Computer & Applied Sciences, Environment Index, Geobase, INSPEC, Metadex, Civil Engineering Abstracts
  • Page Numbers: pp.787-799
  • Keywords: Sewage sludge drying, Solar drying, Transparent cover, Drying chamber modification, HEAT-PUMP SYSTEM, FORCED-CONVECTION, AIR HEATER, ENVIROECONOMIC ANALYSES, PERFORMANCE ANALYSIS, THERMAL PERFORMANCE, CURCUMA-LONGA, CABINET DRYER, FLAT-PLATE, COLLECTOR

Abstract

Disposal of sewage sludge is an important problem for the sustainability of cities. In recycling process of sewage sludge, a big part of energy demand is consumed in the drying process. Therefore, utilizing clean and sustainable energies in recycling process of sewage sludge can be a good solution. In this work, a drying chamber with transparent cover has been designed and analyzed in the process of drying sewage sludge experimentally and numerically. Also, a conventional drying chamber has been tested and its performance compared with modified drying chamber's performance. The main purpose of modifying the drying chamber using transparent cover is to harvest more solar energy in the system and consequently reduction in the drying time. Moreover, in the drying tests a single-pass conventional unglazed solar air collector has been combined with the drying chamber. The performance tests of drying systems have been conducted in two various flow rates including 0.010 and 0.014 kg/s. Experimental and numerical findings demonstrated that using drying chamber with transparent cover reduced the drying time significantly. The obtained average specific energy consumption and specific moisture extraction rate values are in the range of 1.77-2.86 kWh/kg and 0.77-1.34 kg/kWh, respectively. Moreover, levelized cost of heating values were found between 1.7 and 2.0 $-ct/kWh for the system which uses drying chamber with transparent cover.