5.3. Results of the 3rd experiment. (Co-digestion of kitchen waste with cow dung slurry).
5.3.1. Results for the physicochemical characteristics Sl. No Parameter Fresh cow dung slurry Fresh food waste slurry Fresh cow-dung + fresh food waste slurry Digested slurry
1 pH 6.4 6.0 6.2 7.0
2 Total solids (%) 8.5 9.1 8.8 6.16
3 Moisture Content (%) 92 90.5 91.25 94.33
4 Volatile Solids (%) 92.9 94.5 93.7 82.50
5 Percent carbon 2.27 3.03 2.65 0.27
6 Phosphate(mg/100g) 0.24 0.310 0.275 1.010 5.3.1.2. Total solids (%) The total solids which were found to be 8.8% showed a decrease after the retention period of 30 days and were found to be in order of only 6.16 %. Initial total solid in the digester was found 8.8 *14= 6.16. During …show more content…
Moisture Content Along the continuation of anaerobic digestion process, the moisture content increases from 91.25% to 94.33%.The presence of water in the digester is an important parameter affecting anaerobic digestion. The main reason for these is that water makes the movement and growth of bacteria facilitating the dissolution and also helps in mineral transport. The moisture of the digestate increases with the increase of VS and TS reduction.
5.3.1.6. Phosphate Content Phosphate content is an important parameter for the growth of plant. Phosphorous is a macronutrient needed for the growth of plant. Phosphate maintains a stable anaerobic digestion process in the digestate. The amount of phosphorous present at the start of the digestion process was 0.24 mg/100 gram of the waste. The amount of phosphorous was again analyzed at the end of the experiment that is after 30 days. The amount found at the end of the experiment was 1.027 mg/ 100 gram of the waste.
5.3.1.7. Temperature Variation of the Bio …show more content…
The inside temperature was slightly higher than the outside temperature. The average temperature found inside the digester was 34.260C and average outside temperature was found to be 30.450C. The inside temperature was always more than the outside temperature because the microbial degradation of the waste raised the temperature of the digested slurry. Higher temperature generally degrades the waste material faster and hence generates higher biogas yield. The inside temperature was measured by inserting laboratory thermometer through the hole fit inside the cork. A graph has been plotted showing the variation of temperature. The highest volume of biogas production per day was noticed at a temperature of 36.5 inside temperature.
Variation of pH in the digester The variation of the pH of the reactor at the start of feeding with cow dung with water was 6.2. The pH generally increases and decreases. The production of biogas started from the 4th day at a pH of 6.9. The optimum pH at the highest production of pH was 7.04 at the 16th day. The pH generally rises at a higher value showing the methanogenesis phase with highest production in biogas. There is a major drop in pH from 7.7 to 6.8 from 24th day to 26th day. The pH of the waste at the end of experiment was 7.0.
5.3.1.8. Feeding of Waste into the
5.3.1. Results for the physicochemical characteristics Sl. No Parameter Fresh cow dung slurry Fresh food waste slurry Fresh cow-dung + fresh food waste slurry Digested slurry
1 pH 6.4 6.0 6.2 7.0
2 Total solids (%) 8.5 9.1 8.8 6.16
3 Moisture Content (%) 92 90.5 91.25 94.33
4 Volatile Solids (%) 92.9 94.5 93.7 82.50
5 Percent carbon 2.27 3.03 2.65 0.27
6 Phosphate(mg/100g) 0.24 0.310 0.275 1.010 5.3.1.2. Total solids (%) The total solids which were found to be 8.8% showed a decrease after the retention period of 30 days and were found to be in order of only 6.16 %. Initial total solid in the digester was found 8.8 *14= 6.16. During …show more content…
Moisture Content Along the continuation of anaerobic digestion process, the moisture content increases from 91.25% to 94.33%.The presence of water in the digester is an important parameter affecting anaerobic digestion. The main reason for these is that water makes the movement and growth of bacteria facilitating the dissolution and also helps in mineral transport. The moisture of the digestate increases with the increase of VS and TS reduction.
5.3.1.6. Phosphate Content Phosphate content is an important parameter for the growth of plant. Phosphorous is a macronutrient needed for the growth of plant. Phosphate maintains a stable anaerobic digestion process in the digestate. The amount of phosphorous present at the start of the digestion process was 0.24 mg/100 gram of the waste. The amount of phosphorous was again analyzed at the end of the experiment that is after 30 days. The amount found at the end of the experiment was 1.027 mg/ 100 gram of the waste.
5.3.1.7. Temperature Variation of the Bio …show more content…
The inside temperature was slightly higher than the outside temperature. The average temperature found inside the digester was 34.260C and average outside temperature was found to be 30.450C. The inside temperature was always more than the outside temperature because the microbial degradation of the waste raised the temperature of the digested slurry. Higher temperature generally degrades the waste material faster and hence generates higher biogas yield. The inside temperature was measured by inserting laboratory thermometer through the hole fit inside the cork. A graph has been plotted showing the variation of temperature. The highest volume of biogas production per day was noticed at a temperature of 36.5 inside temperature.
Variation of pH in the digester The variation of the pH of the reactor at the start of feeding with cow dung with water was 6.2. The pH generally increases and decreases. The production of biogas started from the 4th day at a pH of 6.9. The optimum pH at the highest production of pH was 7.04 at the 16th day. The pH generally rises at a higher value showing the methanogenesis phase with highest production in biogas. There is a major drop in pH from 7.7 to 6.8 from 24th day to 26th day. The pH of the waste at the end of experiment was 7.0.
5.3.1.8. Feeding of Waste into the