Role of Microbes in Waste Recycling | Sciencing
The organic waste which generated has increased rapidly over the last few decades and a major portion of the total solid waste in developing countries is organic waste, and it is not properly treated for resource recovery such as investigated by Sujauddin, Huda and Hoque  that solid waste management SWM is a multidimensional challenge faced by urban authorities, especially in developing countries, while Moqsud, M. Whereas, the organic wastes contain large amounts of nutrients and various other minerals.
Cristiani et al. Table 3 shows the nutritional values of organic wastes and soil used in this research. Mostafa et al. Moqsud, Omine and Yasufuku  and Moqsud et al. Allen and Bennetto  , Daniel et al. Bennetto  and Logan et al. Habermann and Pommer  were to develop a low maintenance fuel cell system with long-term stability with sulphide storage capacity.
Hong et al. Khalid et al. Microbial fuel cell using sewage sludge as fuel was studied by Jiang et al. Spiegel and Preston demonstrated energy from anaerobic digester gas ADG. Zang et al. Table 2. Environmental problems due to livestock farming in Japan Table 3.
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Nutritional values of organic waste and soil. Moqsud, M. Wang et al. Velasquez-Orta, Curtis and Logan  investigated algae in microbial fuel cells. Jauharah, Boris and Raghavan  developed electricity from a mix of fruit and vegetable wastes.
Brahmaiah, P. Resch, Hass and Faber  considered the production of electricity or biofuels using innovative technologies and renewable sources is a global priority in terms of energy strategies. This research becomes very important and very interesting because of the increasing need for alternative energy while the amount of non-renewable fuel is decreasing.
MFC has been well established for almost one hundred years.
Valuable interdisciplinary research
However, Jessica Li  investigated this capability did not exceed laboratory-based experiment until the 20th century when research on this subject and the creation of MFCs received sporadic approach. The objective of this study is to focus on and prove the ability of some cheap and abundant-organic wastes such as cow dung, chicken dropping and leaf mold mixed with soil as a very prospective substrate for bioelectricity generation.
Thus, it develops a microbial fuel cell that generates green and safe electricity using animal dungs and leaf mold mixing with soil as an efficient, renewable and an eco-friendly solution for organic waste management. The EM which used in this work was for each case to start the bioelectricity generation and to reduce possible odour from organic wastes during the investigation. The soil used in this work as they are thought to increase not only the physical volume of samples properties and the optimum content but it also to increase the nutrient ability supplying food for microorganism to generate electricity.
Some advantages that arise in using of carbon felt such as a large surface area that offers sufficient reaction sites for the electron-transfer re-actions, their suitability for mass production and good process ability, but their properties vary with the raw material used for their fabrication. The property of the electrodes shows at Table 4. Furthermore, Figure 1 show the SEM images of carbon felt as electrodes. The chicken droppings and leaf mold were collected from Japan Agricultural Office, Ube city branch. In this study the MFCs employed a blend of some organic wastes and soil which over a testing time within 21 days.
Figure 2 describes the schematic diagram for the MFC in this study. Then, an amount of each organic waste g , g of soil and add 4 g of EM were blended with added ml of water until mixed completely. Table 4. Properties of carbon felt. Figure 1. SEM image of carbon felt as electrode. The blended sample was poured into the container. Carbon felt was used for both electrodes anode and cathode.
The anode was set approximately 5 cm below the surface of the compost, while the cathode was placed immediately above. Figure 2. The schematic diagram of the microbial fuel cell used in this study. The area of electrodes was kept the same as the cell areas cm 2. Experiments were conducted with pure samples and mixed samples. In the anode compartment of MFC devices, microorganisms metabolize a substrate such as sugar in absence of oxygen, and they produce carbon dioxide, protons and electrons as describe below:.
Since the publication of the paper of Dean , loss on ignition LOI has been widely used as a method to estimate the amount of organic matter. Walter, E. We conducted LOI test of the four samples used in this research. The content of organic matter is to have greatly influence to the amount of power generation in this microbial fuel cell.
Table 5 shows the LOI test results of the four samples. The sample which contains the most organic matter of The lowest value of It is considered that more organic substances in a mixture of organic waste with soil that can influence on more voltage generation than soil only.
Then they were added in to the each acrylic rectangular after blended completely. All samples parameter condition was showed by Table 6 as described below. Soil and organic wastes in this work were mixed with a ratio of the same volume to generate bioelectricity in a microbial fuel cell MFC. Quanguo, Jianjun and Du  investigated MFC as a device that can convert chemical energy in influent substances to electricity via biological pathways.
As there are many microorganisms in the soil. Fedorovich et al. In microbial fuel cells MFCs , many microorganisms work in a consortium state, meaning they are not in the same pure colony, but. Table 5. Result of the loss on ignition tests. Table 6. Parameter conditions for pure samples.
While Geobacter metallireducens is a class of bacteria from the genus geobacter unique because it can produce like filaments that act as nanowires to transfer electrons from outside the cell to the insoluble electron acceptor such as iron minerals and most likely to electrodes. It is considered that more voltages can be obtained by mixing soil with organic matter.
Moreover, the blended soil and some of organic waste in this work as they are thought to increase the physical volume of samples properties and it increases the nutrient supply ability for microorganism. The type and number of microorganisms which survive are different by region in the distribution of the soil. The mixture of organic constituents in the waste and microorganisms in the soil are expected to lead the higher values of output voltage.
Table 7 illustrates the parameter condition for mixed samples.https://quiclicofcyata.cf
Microbial Responses to Different Operating Practices for Biogas Production Systems
Since MFC is the source of direct current DC , in this experiment we calculate the magnitude of the potential difference voltage between the anode and cathode poles. The voltage which generated across the resistor and capacitor was monitored every day at 1 pm. It is estimated that at that time is the most appropriate time for research measurement. Polarization curve and power density-current curves were investigated as described by Logan and Regan  who formulated polarization curve and power density-current curves by using different resistors and internal resistances and power densities.
Electrode output was measured in volts V against time. From this, it is possible to. Table 7.
Parameter condition for mixed samples. Normally, the anode area is taken as the electrode area. For example, if the electrode material is rectangular the area will be simply the length multiplied by width. Furthermore, the root-mean-square deviation RMSD is used as a statistical analysis which is a good accuracy measurement.