Felix Garlipp

Upflow anaerobic solid-state (UASS) digestion of horse manure: Thermophilic vs. mesophilic performance

Energetic use of complex lignocellulosic wastes has gained global interest. Thermophilic digestion of horse manure based on straw was investigated using the upflow anaerobic solid-state (UASS) process. Increasing the organic loading rate from 2.5 to 5.5gvsL(-)(1)d(-)(1) enhanced the average methane production rate from 0.387 to 0.687LCH4L(-)(1)d(-)(1), whereas the yield decreased from 154.8 to 124.8LCH4kgvs(-)(1). A single-stage and two-stage process design showed almost the same performance. Compared to prior experiments at mesophilic conditions, thermophilic conditions showed a significantly higher efficiency with an increase of 59.8% in methane yield and 58.1% in methane production rate. Additional biochemical methane potential (BMP) tests with two types of horse manure and four different bedding materials showed that wheat straw obtained the highest BMP. The results show that the thermophilic UASS process can be the key to an efficient energy recovery from straw-based manures.

Anaerobic digestion of horse dung mixed with different bedding materials in an upflow solid-state (UASS) reactor at mesophilic conditions.

Aim of this study was to investigate the use of upflow anaerobic solid-state (UASS) digestion for treating horse manure. Biochemical methane potential (BMP) tests conducted for varying mixtures of dung (hay and silage feed) and bedding material (wheat straw, flax, hemp, wood chips) showed that straw mixed with hay horse dung has the highest potential of [Formula: see text] . Continuous mesophilic digestion was conducted for 238 days using a single-stage UASS reactor (27 L) and a two-stage UASS system with an anaerobic filter (AF, 21 L). Increasing the organic loading rate (OLR) from 2.5 to 4.5 g vs L(-1)d(-1) enhanced the methane rate of the single-stage reactor from 0.262 to 0.391 LL(-1)d(-1) while the methane yield declined from 104.8 to 86.9 L kg vs(-1). The two-stage system showed similar yields. Thus, for solid-state digestion of horse manure a single-stage UASS reactor appears sufficient.

Soil, slurry and application effects on greenhouse gas emissions

In conjunction with soil type and climate, the use of nitrogen fertilizers is a major factor affecting nitrous oxide emissions. This study compares injection of pig slurry and pig slurry digestate at 15 or 20 cm depths with trailinghose application followed by immediate incorporation. The work was based on a laboratory microcosm experiment with undisturbed soil cylinders (0–30 cm depth) from three arable soils (Histosol, Gleysol and Plaggic Anthrosol). Soil cylinders were fertilized with pig slurry and pig slurry digestate (150 kg N/ha) and emissions of N 2 O, CH 4 and CO 2 were monitored. The comparison of application techniques over a 37-day period show that soil type and ap plication technique, had a strong (P < 0.001) impact on N 2 O emissions. Fertilization with pig slurry showed no significantly higher N 2 O emissions than pig slurry digestate. Fertilizer injection significantly increased N 2 O emissions compared to fertilization with a trailing-hose with incorporation.

Partikelabscheidetechnologie für Einstreumaterialien und Raufuttermittel

In Bezug auf die Reduzierung luftgetragener Partikel in der Pferdehaltung steht primar die Behandlung der Hauptkontaminationsquellen von Schwebstaub im Vordergrund. Deshalb war es das Ziel dieser Studie, den Einfluss der mechanischen Behandlung verschiedener Einstreumaterialien und Raufuttermittel mithilfe einer neu entwickelten Technologie auf die Schwebstaubkonzentration und den Schimmelpilzgehalt unter Laborbedingungen zu untersuchen. Durch die Behandlung konnte eine Schwebstaubreduzierung von bis zu 90 % in den Partikelfraktionen PM20, PM10, und PM1.0 erreicht werden. Die Analyse des Gehaltes an Schimmelpilzen zeigte eine bis zu 92 %ige Reduzierung. In der Partikelfraktion PM2.5 konnte der Schwebstaub um bis zu 70 % reduziert werden.