Impact of composting strategies on the degradation of nonylphenol in sewage sludge

Abstract

Nonylphenol can be present in sewage sludge, and this can limit the use of the sewage sludge to amend soil. Composting is one of the most efficient and economical methods of making sewage sludge stable and harmless. The nonylphenol degradation rates during composting with added bulking agents and with aeration applied were studied. Three organic bulking agents (sawdust, corn stalk, and mushroom residue) were added to sewage sludge, and the effects of the bulking agents used and the amount added on nonylphenol degradation were determined. The highest apparent nonylphenol degradation rate (71.6 %) was found for sewage sludge containing 20 % mushroom residue. The lowest apparent nonylphenol degradation rate (22.5 %) was found for sewage sludge containing 20 % sawdust. The temperature of the composting pile of sewage sludge containing 20 % sawdust became too high for nonylphenol to be efficiently degraded, and the apparent nonylphenol degradation rate was lower than was found for sewage sludge containing 10 % sawdust. Increasing the ventilating time from 5 to 15 min increased the apparent nonylphenol degradation rate from 19.7 to 41.6 %. Using appropriate aerobic conditions facilitates the degradation of nonylphenol in sewage sludge, decreasing the risks posed by sewage sludge applied to land. Adding too much of a bulking agent can decrease the amount of the nonylphenol degraded. Increasing the ventilating time and the amount of air supplied can increase the amount of nonylphenol degraded even if doing so causes the composting pile temperature to remain low.

Microbial community succession of cow manure and tobacco straw composting

“…Temperature stands as a crucial indicator throughout composting, reflecting the composting process and alterations in microbial activities (Zheng et al, 2015). The cow manure and tobacco straw composting mixture's temperature rapidly increased to 50°C within 1 week (Figure 1A, Supplementary Table S1).…”

Fate and toxic effects of environmental stressors: environmental control

“…Composting is one of the most efficient and economical methods of making sewage sludge stable and harmless. Zheng et al (2015a) studied the nonylphenol degradation rates during composting under the conditions of adding bulking agents (sawdust, corn stalks, and mushroom residue) and applying aeration. Addition of 20 % mushroom residue and 20 % sawdust to the sewage sludge led to the highest (71.6 %) and lowest (22.5 %) apparent nonylphenol degradation rates, respectively.…”

Process type is the key driver of the fate of organic micropollutants during industrial scale treatment of organic wastes

“…All OW treatment processes have an effect on some of the OMPs present in wastes: anaerobic digestion and composting as biological treatment processes are known to dissipate or degrade PPs (Ezzariai et al, 2018;Wohde et al, 2016;Spielmeyer 2018), nonylphenol ethoxylates and NP (Zheng et al, 2015;2018) and PAHs (Brändli et al, 2007;Aemig et al, 2016). The effect of these treatment processes has been shown in lab and pilot scale experiments (Phan et al (2018) for sludge anaerobic digestion; Spielmeyer et al (2015) for manure anaerobic digestion; Geng et al (2016) for sludge drying and liming) and in some studies where in situ sampling was performed on industrial sites (Lillenberg et al (2010) for sludge composting; Martin et al (2015) for sludge anaerobic digestion and composting; Mailler et al (2017) for sludge anaerobic digestion), each time for a small selection of micropollutants.…”