Effects of Land‐Applied Ammonia Scrubber Solutions on Yield, Nitrogen Uptake, Soil Test Phosphorus, and Phosphorus Runoff

• Published in: Journal of environmental quality 2018-03, Vol.47 (2), p.263-269
• Main Authors: Martin, Jerry W., Moore, Philip A., Li, Hong, Ashworth, Amanda J., Miles, Dana M.
• Format: Article
• Language: English
• ISSN: 0047-2425; 1537-2537
• DOI: 10.2134/jeq2017.09.0383

Ammonia (NH3) scrubbers reduce amounts of NH3 and dust released from animal rearing facilities while generating nitrogen (N)‐rich solutions, which may be used as fertilizers. The objective of this study was to determine the effects of various NH3 scrubber solutions on forage yields, N uptake, soil‐test phosphorus (P), and P runoff. A small plot study was conducted using six treatments: (i) an unfertilized control, (ii) potassium bisulfate (KHSO4) scrubber solution, (iii) aluminum sulfate [Al2(SO4)3 ⋅14H2O, alum] scrubber solution, (iv) sodium bisulfate (NaHSO4) scrubber solution, (v) sulfuric acid (H2SO4) scrubber solution, and (vi) ammonium nitrate (NH4NO3) fertilizer. The scrubber solutions were obtained from ARS Air Scrubbers attached to commercial broiler houses. All N sources were applied at a rate of 112 kg N ha−1. Plots were harvested approximately every 4 wk and soil‐test P measurements were made, then a rainfall simulation study was conducted. Cumulative forage yields were greater (P < 0.05) for KHSO4 (7.6 Mg ha−1) and NaHSO4 (7.5 Mg ha−1) scrubber solutions than for alum (6.7 Mg ha−1) or H2SO4 (6.5 Mg ha−1) scrubber solutions or for NH4NO3 (6.9 Mg ha−1). All N sources resulted in higher yields than the control (5.1 Mg ha−1). The additional potassium in the KHSO4 treatment likely resulted in higher yields. Although Mehlich‐III‐extractable P was not affected, water‐extractable P in soil was lowered by the alum‐based scrubber solution, which also resulted in lower P runoff. This study demonstrates that N captured using NH3 scrubbers is a viable N fertilizer. Core Ideas Most of the nitrogen excreted by broiler chickens is lost to the atmosphere. The ARS Air Scrubber can use acid salts to scrub ammonia from poultry house exhaust. Fertilizing with scrubber solutions resulted in higher yields than ammonium nitrate. Alum‐based scrubber solutions reduced phosphorus runoff. Nitrogen captured using ammonia scrubbers is a viable fertilizer.