Recovery efficiency of nitrogen from liquid and solid fractions of pig slurry obtained using different separation technologies

Abstract

The characteristics of solid (SF) and liquid (LF) fractions resulting from solid–liquid separation of pig slurry depend on the separation technique used. It can be assumed that the separation technique will also affect the nitrogen (N) availability to plants. A pot experiment was performed with ryegrass to compare the N‐recovery efficiency of SFs and LFs obtained with four frequently used separation techniques (centrifugation [Cent], sediment settling during 20 h [Sed], enhanced settling during 20 h by addition of cationic polyacrylamide [Sed+PAM], sieving [Siev], sieving followed by treatment of the resulting liquid fraction by PAM addition [Siev+PAM]) with the untreated slurry (US) and an unfertilized control. Increases (2–17%) of ryegrass dry matter yield (DMY) were obtained in LF treatments relative to US. However, this increase was statistically significant only for the Siev+PAM‐L treatment. A significant decrease of ryegrass DMY was observed in SF treatments relative to US. All treatments with SFs led to similar values of DMY while only small differences were observed between treatments receiving LFs. A significant correlation (R2 = 0.968) was observed between the total DMY and the NH$ _4^+ $ ‐ N : Ntot ratio of the fraction applied suggesting that this is a major parameter to be considered when comparing separation techniques. Overall, the separation techniques showed only a weak effect on the dry matter yields and on the N ‐ recovery efficiency from LF and SF although they strongly affected the nutrient concentration and speciation in each fraction.

Long-Term Fertilizer Reduction in Greenhouse Tomato-Cucumber Rotation System to Assess N Utilization, Leaching, and Cost Efficiency

“…Therefore, we found that organic fertilization carries a higher risk of N leaching than chemical fertilization, which is consistent with some earlier findings [46,47], despite more research having widely shown that the application of organic N fertilizer would cause a decrease in N leaching than inorganic [48][49][50]. Most of the nitrogen in organic fertilizer exists in the form of macromolecular, which can only be absorbed by plants after a certain period of dissolution by a series of microbial-mediated steps [51,52]. Therefore, compared with inorganic nitrogen from chemical N, it is difficult to be directly used by crops.…”

Technische bovengrenzen van P2O5 gehalte dikke fractie na scheiding drijfmest met decanteercentrifuge : Update 2020

“…In onderstaande tabellen worden de resultaten van het literatuuronderzoek samengevat voor rundveeen varkensdrijfmest, voor zover deze voldeden aan de in paragraaf 2.2 genoemde 3 criteria. De resultaten van literatuurbronnen die niet voldeden aan een of meerdere criteria (Fangueiro et al, 2015; een aantal metingen uit Derikx, 2019;Gastel et al, 1997;Lemmens et al, 2007;Rexilius, 1990;Schön et al, 1989;Vu et al, 2016) zijn niet opgenomen in Tabel 5 en 6 en worden niet nader gebruikt.…”

Technische bovengrenzen van P2O5 gehalte dikke fractie na scheiding drijfmest met decanteercentrifuge : Verkennende studie - versie januari 2017

“…De resultaten van literatuurbronnen die niet voldeden aan een of meerdere criteria (Fangueiro et al, 2015;Gastel et al, 1997;Lemmens et al, 2007;Rexilius, 1990;Schön et al, 1989;Vu et al, 2016) zijn niet opgenomen in Tabel 5 en 6 en worden niet nader gebruikt.…”