Treatment of Pyrolytic Eco-toilet Waste: Characterization of Feces-Based Biochar Produced from Different Temperatures and Their Effects on Urine Properties and Fractions

摘要

Toilets excrement (feces and urine) directly affects human health and living environment. Poor toilet sanitation increases economic losses and disease transmission. Thus, research and development of eco-toilets has attracted considerable attention. In this study, samples of human feces were collected as feedstock, pyrolyzed for biochar production, and then added to urine as pretreatment for eco-toilets. Feces-based biochar produced at different pyrolysis temperatures (300-600 ℃) was characterized. The effects of feces-based biochar produced at different pyrolysis temperatures on the properties and fractions of urine were investigated. The feces-based biochar promoted the stabilization of urine through urea hydrolysis. The feces-based biochar produced at 600 ℃ exerted adsorption effects on TP, TN, and NH_4~+-N. The protein-like substances released from the feces-based biochar produced at high pyrolysis temperatures (500 ℃ and 600 ℃) increased TN content. In addition, the feces-based biochar produced at high pyrolysis temperatures (500 ℃ and 600 ℃) decreased the DOM content in urine. The substances released from the feces-based biochar affected the composition and properties of urine through liquid-phase reactions. The correlation between property parameters and DOM parameters in urine was also analyzed. The results of study may help create novel eco-toilet design concepts and provide valuable treatment information for urine and feces.