Submitted to: Proceedings of the American Society of Agricultural and Biological Engineers International (ASABE)
Publication Type: Proceedings
Publication Acceptance Date: 7/1/2015
Publication Date: 7/26/2015
Citation: Garcia, M.C., Vanotti, M.B., Szogi, A.A. 2015. Recovery of nitrogen from swine manure containing high-ammonia using gas-permeable membrane technology and reduced chemicals. In: Proceedings of the American Society of Agricultural and Biological Engineers International Meeting, July 26-29, 2015, New Orleans, Louisiana. doi:10.13031/aim20.2187976.
Technical Abstract: We are presenting a new and effective way of recovering ammonia from liquid manures. The recovery of nutrients from wastes for re-use as concentrated plant fertilizers is a new paradigm in manure management. In the work presented in this paper a new process using gas-permeable membranes at low pressure was applied to raw swine manure containing high-ammonia (2,390 mg NH4+-N/L) to recover the nitrogen. The process was refined further. To increase the ammonium (NH4+) recovery rate (that is normally carried out using an alkali), in this study we used low aeration and nitrification inhibition. The aeration reacted with the natural alkalinity, which released OH- and increased the manure pH above 8.5. This pH increase promoted gaseous NH3 release from the manure and rapid permeation through the submerged membrane with excellent (98%) recovery of the N. Ammonia emissions losses were less than 1.5%. The new approach substituted for large amounts of alkali chemical that were needed to obtain the same effect and reduced the operational costs of NH4+ recovery by 57%.