Evaluation of solar sludge drying alternatives by costs and area requirements

Thermal drying is a common method to reach above 90% dry solids content (DS) in sludge. However, thermal drying requires high amount of energy and can be expensive. A greenhouse solar dryer (GSD) can be a cost-effective substitute if the drying performance, which is typically 70% DS, can be increased by additional heat. In this study feasibility of GSD supported with solar panels is evaluated as an alternative to thermal dryers to reach 90% DS. Evaluations are based on capital and O&M costs as well as area requirements for 37 wastewater treatment plants (WWTPs) with various sludge production rates. Costs for the supported GSD system are compared to that of conventional and co-generation thermal dryers. To calculate the optimal costs associated with the drying system, an optimization model was developed in which area limitation was a constraint. Results showed that total cost was minimum when the DS in the GSD (DSm,i) was equal to the maximum attainable value (70% DS). On average, 58% of the total cost and 38% of total required area were associated with the GSD. Variations in costs for 37 WWTPs were due to differences in initial DS (DSi,i) and sludge production rates, indicating the importance of dewatering to lower drying costs. For large plants, GSD supported with solar panels provided savings in total costs especially in long term when compared to conventional and co-generation thermal dryers.


Arıtma Çamurlarının Kurutulmasında Sera Tipi Kurutucular ve Güneş Panellerinin Birlikte Kullanımının Maliyetler Bazında İncelenmesi
Kurt, Mayıs; Aksoy, Ayşegül; Sanin, Faika Dilek (2016-01-01)
Çamurun kurutulması hem çamurun hacmini azaltarak depolama amaçlı hacim ihtiyacında hem de sızıntı suyu miktarında azalma sağlamaktadır. Çamurun ek yakıt ve tarımsal amaçlı kullanımı gibi yararlı kullanım yöntemleri ile değerlendirilmesi için çoğu kez kurutma gereklidir. Çamur kurutma yöntemleri genel olarak termal kurutma ve güneşle kurutma şeklinde değerlendirilmektedir. Termal kurutma, atıksu arıtma tesisi çamurunun kurutulup %90 katı madde oranına erişmesi için kullanılan geleneksel bir...
Evaluation of solar sludge drying alternatives on costs and area requirements
Kurt, Mayıs; Aksoy, Ayşegül; Sanin, Faika Dilek; Department of Environmental Engineering (2014)
There are basically two common sludge drying methods, thermal drying and solar drying. While thermal drying requires high amount of energy, solar drying cannot typically attain the 90 % DS requirement. The literature studies emphasize the benefits of solar drying used as GSD (greenhouse solar dryer) to reduce energy requirement but these dryers cannot achieve 90 % DSC without any auxiliary heat. Therefore, use of solar panels as auxiliary heat source was evaluated in this study. To calculate how much energy...
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Citation Formats
M. Kurt, A. Aksoy, and F. D. Sanin, “Evaluation of solar sludge drying alternatives by costs and area requirements,” WATER RESEARCH, pp. 47–57, 2015, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/41023.