Biogas-powered evaporative cooling for smallholder dairy farmers' evening milk: Zeolite characterization and regeneration. (August 2019)

• Record Type: Journal Article
• Authors: Ndyabawe, Kenneth; Brush, Ryan; Ssonko, Richard E.; Kisaalita, William S.
• Is Part Of: Sustainable energy technologies and assessments. Volume 34(2019)
• Page Start: 126
• Page End: 132
• Publication Date: 2019-08
• Subjects: Zeolite -- Evaporative cooling -- Food security -- Dairy farming -- Alternative energy; Renewable energy sources -- Periodicals; Energy development -- Technological innovations -- Periodicals; Electric power production -- Periodicals; Energy storage -- Periodicals; 333.79
• DOI: 10.1016/j.seta.2019.05.003
• Languages: English
• ISSNs: 2213-1388

Abstract

Abstract: A low-capacity (15.5-L) evaporative cooler, utilizing zeolite as an adsorbent, for saving smallholder dairy farmers' evening milk, was not well received due several factors, addressed in the second generation higher capacity (>50 L) design. Like the first generation the new design uses zeolite and is powered by biogas. The first development step was to establish a protocol for testing commercially available zeolites to determine zeolite suitability for use in the design and to characterize the performance of a zeolite biogas-powered regenerator. Using an in-house developed protocol, zeolite beads of diameters 2.5–5 mm were tested and we found that 10 angstrom (Å) zeolites have a higher water adsorption capacity (6–7%) in comparison to 3 Å zeolite beads, suggesting that larger pore zeolites provide higher cooling capacity. However, large pore zeolite beads showed up to 18 times variance in repeat water adsorption compared to 3 Å zeolite, indicating that zeolite of small pores may provide more cooling cycles. Our biogas powered regenerator achieved and maintained the regeneration temperature of 200 °C when tested with both propane and biogas. This result affirms that our system can be operated on the farm using biogas as the energy source.