Effect of a Polymer on Mitigating Ammonia Emission from Liquid Dairy Manure

Abstract

Reducing ammonia (NH3) emissions from manure has been a great interest for academic, regulators, dairy farmers, and the general public. Fresh liquid dairy manure was collected from a dairy central pit. A polymer (MTMTM) was tested at five different doses to determine if the polymer had any effects on reducing NH3 emission from the manure. Ogawa NH3 passive samplers were used to trap NH3 emitted from the manure for two, four, six, eight, 12, and 24 hours during two separate tests, respectively. Samples collected via the passive samplers were analyzed for ammonium-N (NH4-N) concentrations by a QuickChem 8500 system. Manure pH values were monitored before and after applying the polymer to the manure. The average concentration reductions of NH4-N in the extractant were 8.1%, 20.7%, 36.5%, 54.5%, and 88.2% for the polymer Treatments 1 to 5 over the entire test period, respectively. Statistically significant differences of the NH4-N concentration and manure pH were detected between the treatments and controls. However, a lower dose treatment (0.5 ml polymer/5 l manure) did not show significant differences of the NH4-N concentration and pH from control for the two-, four-, six-, and eight-hour samples, but showed significant differences for both the 12- and 24-hour samples. The test results have shown that a higher dose of polymer led to a lower manure pH and a lower NH3 emission. Further studies are needed to test if the pH adjustment was the only mechanism for reducing NH3 emission or other effects existed as well.

Smanjenje emisije amonijaka (NH3) iz tečnog stajnjaka je od velikog interesa za istraživače, nadzorne organe, vlasnike farmi muznih krava i javnost uopšte. Svež tečni stajnjak je skupljan iz centralnog kolektora na farmi. Polimer (MTMTM) je testiran u pet različitih doza da bi se ispitao uticaj polimera na smanjenje emisije NH3 iz đubriva. Ogawa NH3 pasivni sakupljači uzoraka su korišćeni za sakupljanje NH3 oslobođenog iz đubriva tokom perioda od 2, 4, 6, 8, 12 i 24 časa, u dva odvojena testa. U uzorcima sakupljenim pasivnim sakupljačima analizirana je koncentracija amonijaka-N (NH4-N) korišćenjem aparata QuickChem 8500. pH vrednosti su praćene pre i posle dodavanja polimera u đubrivo. Prosečno smanjenje koncentracije NH4-N u ekstraktantu je bilo 8.1%, 20.7%, 36.5%, 54.5% i 88.2% pri tretiranju različitim dozama polimera u testovima 1 do 5. Statistički značajne razlike u koncentraciji NH4-N i pH vrednosti đubriva su uočene upoređivanjem tretiranja različitim dozama i u različitim vremenskim periodima. Međutim, tretiranje nižim dozama polimera (0.5 ml polimera na 5 l đubriva) nije dovelo do značajnog smanjenja u koncentraciji NH4-N i pH vrednosti u kontrolnim uzorcima izmerenim posle 2, 4, 6 i 8 časova, ali je dovelo do značajne razlike između uzoraka izmerenih posle 12 i 24 časa. Rezultati ispitivanja su pokazali da više doze polimera dovode do niže pH vrednosti đubriva i smanjenja emisije NH3. Dalja ispitivanja su neophodna da bi se ispitalo da li je podešavanje pH vrednosti jedini mehanizam za smanjenje emisije NH3 ili postoje i drugi mehanizmi.