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Three laboratory scale systems were operated to study the anaerobic co-digestion of sewage sludge with the excess activated sludge and cattle manure which contained low COD concentration. The experiments were performed to evaluate the effects of different methods of pretreatment. Since the poor organic substrate, the organic loading rate(OLR) was designed about 1.6kg total solids(TS)(l *d)-1 and the hydraulic retention time was controlled from 78days to 53days throughout the experiment to investigate the effects of the input on overall stability. When the digesters got stabilized, the COD removal efficiencies were 61%, 89% and 54%, respectively, and the pH value fluctuated little in the three digesters. The results indicated that the treatment of 1g volatile solids(VS) of SSEASCM on semi-continuous co-digestion generated more than 200ml of biogas on average. Thus, anaerobic co-digestion of the mixed sludge provided a means for low COD waste treatment and produced renewable energy.

Population growth, industrialization and technological advances have significantly increased waste production, waste collection, transportation and disposal induced significant costs. Waste could be considered a resource that allows nations to reduce the consumption of primary raw materials, protect natural resources and improve economic revenues by reducing environmental pressures. Zero waste approach for sustainable waste management has been approved and implemented globally. The present study aimed to investigate the basic zero-waste management in Turkey. Thus a scale that included eight items was developed and validity and reliability of the scale were analyzed. Explanatory factor analysis (EFA) was initially applied. Then, the fitness of the model was tested with confirmatory factor analysis (CFA). Cronbach's α (internal consistency coefficient) was calculated as 0.778. Chi-square test, RMSEA, GFI and CFI fit indices were employed in the first-order confirmatory factor analysis conducted on the whole sample. Chi-square was calculated as 1.310 in confirmatory factor analysis. Also, comparative and absolute fit indices were determined as follows: RMSEA=0.035, GFI=0.976, CFI=0.987, RMR=0.030. The analysis of the findings revealed that “Zero Waste Management Behavior” scale fit indices demonstrated excellent model fit for the findings. Furthermore, there were no significant differences between one-way ANOVA and T test results on participant statements based on gender, while there were significant differences between these variables based on age, education level and the region of residence.

The biogas production of pretreated corn stover has been determined in different soaking durations. Batch anaerobic digestion applies three different soaking durations in sulfuric acid pretreatment under room temperature. The study aimed to probe the effect of soaking durations during sulfuric acid pretreatment. The experiment was conducted in 600 mL digesters at room temperature. Biogas volume was measured using the water displacement method every three days. The observed cumulative biogas yields varied between 48.74 mL/g VS and 99.95 mL/g VS. The highest biogas yield was obtained when corn stover was soaked in sulfuric acid for 6 hours. The 24 h-pretreated corn stover got the lowest biogas yield. The statistical result proved a significant effect of soaking durations on biogas production (p < 0.05). The logistic model provided a better fit than the first-order model, with R2 values ranging from 0.9923 to 0.9987 and divergence between experimental and predicted values varying between 0.12% and 1.48%.