An Improved Vermicomposting System Provides More Efficient Wastewater Use of Dairy Farms Using Eisenia fetida

Abstract

Dairy cattle farming produces large amounts of wastewater and it causes environmental pollution and eutrophication of rivers, but the nutrients in the waste could be recycled. Here, an improved vermicomposting system was applied to dairy farm wastewater, and wastewater with a nitrogen content of 100 mg/L and 200mg/L tested with different combinations of organic substrates such as cow manure and rice straw in rural solid waste. Results showed that earthworms could continuously grow, wastewater (N 100mg/L) mixed with rice straw corresponding to the most significant gained weight for Eisenia fetida earthworms (2.38 to 9.12-fold), and the earthworms’ weight was positively correlated with the C/N ratio, organic matter content, and pH. Compared to the initial state, the system significantly changed physicochemical parameters in nutrients, such as the percentages of total nitrogen, phosphorous, and potassium, which were found to increase in vermicomposting while organic matter content, C/N ratio, and cellulose declined as a function of the vermicomposting period, and the final vermicompost was better for the absorption of plants. These results suggest that continuous wastewater addition improved the effective transformation of organic waste to allow valorizing a broad range of organic residues, and avoid the risk of environmental pollution in dairy cattle farming.

Investigating the Effect of Vermifiltration with Different Bulking Agents on Some Important Properties of Municipal Sewage Influent

“…The results also showed that the highest concentration of P was seen in 10% v/v rice husk when treated by vermicomposting (RH10+EW) (Table 3). These results are consistent with the findings of Liu et al [39]. They observed that vermicomposting significantly changed physicochemical parameters of wastewater in nutrients, such as the percentages of total nitrogen, phosphorous, and potassium, which were found to increase during vermicomposting.…”

Sustainable organic waste management using vermicomposting: a critical review on the prevailing research gaps and opportunities

“…Liu et al 44 initiated a study involving the earthworm Eisenia fetida was used to remove the dairy waste into a useful product thereby reducing the eutrophication problem. In this experiment various concentration of dairy water mingled with organic waste such as cow dung, rice straw had been used.…”

New Advances on Nutrients Recovery from Agro-Industrial and Livestock Wastes for Sustainable Farming

“…This observation was used to propose new parameters (i.e., WEN, TOC/WEN) to optimize the composting process. An improved vermicomposting system was proposed to treat dairy wastewater, rice, straw, and cow manure and to recover nutrients [10]. The results of this study showed that this can represent a feasible method for the simultaneous disposal of organic wastes, especially in poor countries, because it incurs lower costs and has a lower impact on the environment.…”