The biogas production rate is 18.5 ft3 biogas/lb (1.15 m3 biogas/kg) VS destroyed. The first was to keep the level of the dome and the pressure in the dome within the recommended ranges of the manufacturer; the second was to make sure that there was enough gas to run the IC engine during the peak power window, 12 to 6 pm. For example, increasing biogas production through anaerobic digestion of food waste would increase the use of renewable fuels throughout California and add to its renewables portfolio. We use cookies to improve your website experience. Measured value for some property during the baking of injera. Injera baking using a three-stone fireplace as shown in Figure 1 is very inefficient and consumes a lot of firewood. The results are summarized in Table 6 and the values between the portable biogas analyzer and the certified lab are comparable. It is more affected by high temperature, and the material selected for this purpose, stainless steel, resists a temperature of flame. OCDD was the only single PCDD/F species detected in the IC engine exhausts, at an average concentration of 9.4 × 10−9 mg/dscm. Using 49 holes, with 10 mm gaps between holes, arranged in a circular pattern, gives a total circumference of  mm as shown in Figure 7. The gas pressure in the throat is 99 kPa, which is found from the parameter labeled in table and Equation (12). The effluent from the H2S removal system goes through a condenser to reduce moisture content before being fed to two 2,500-lb (1,135-kg) activated carbon adsorbers (Model SAG 48V, Applied Filter Technologies, Snohomish, WA) for siloxanes removal. Yields from anaerobic digestion can be as high as 3,200 standard cubic feet (scf), 90.6 m3, methane per ton of raw food waste. Tests on IC engine emissions were also conducted by a Bay Area AQMD-certified source tester (Total Air Analysis, Carson, CA) on two separate days during the study period. The gas will leave the digester at a pressure of 74.2 kPa from the gas holder as shown in Figure 13. As an example, the “Permit Guidance for Anaerobic Digesters and Co-digesters” provides the basic permitting framework and requirements for anaerobic digestion projects in California (California EPA, 2011). This baking process is commonly made by a biomass-operated stove (i.e., three-stone fireplace and improved injera baking stoves), on a clay plate known as mitad. It should be noted that preprocessing of food waste is often required because WWTP digesters can be damaged by highly fibrous material, metal, and plastic. The output power from flame combustion required to bake injera is 5.696 kW. The incoming raw wastewater goes through bar screens, aerated grit chambers, primary clarifiers, biological treatment units (i.e., biotowers + fine-bubble aeration tanks for activated sludge process), secondary clarifiers, chlorine contact tanks, and then dechlorination before discharge into central San Francisco Bay through a 2-mile (3.2-km) outfall. Dioxins/furans in the IC engine exhausts from tests conducted by the source tester. Biopower can diversify energy supply and improve energy resiliency. 1 gallon/day = 3.785 L/day; 1 lb/day = 0.454 kg/day. Table 14 tabulates the masses of the detected compounds in the collected samples and the corresponding concentrations (mg/dry standard cubic meter), calculated using the mass and the total sample volume (80.11 and 81.49 ft3 [2.27 and 2.31 m3] for 10/29/14 and 10/30/14, respectively). The average mass of the dough is around 598 grams per each injera baked. During combustion, H2S will react with oxygen to form SO2, then sulfurous acid (H2SO3) and sulfuric acid (H2SO4). However, it should be noted that the concentrations of D3 in the effluent of the H2S adsorbers were higher than those in the raw biogas on both days (295 vs. <13.0 and 270 vs. 204 ppbv). The shape of the burner port is critical for efficient utilization of the biogas fuel so the designed burner port is believed to discharge the fuel from the pipeline without loss. The appropriate amount of waste available and its type should be known before the design of the digester. Technical specifications of ECOM J2KN. As shown, the average TS values for PS, TWAS, FOG, and food waste were 4.4 ± 0.6%, 4.5 ± 0.7%, 3.1 ± 2.1%, and 20.6 ± 3.3%, respectively. Table 9. Hydrogen sulfide is a toxic product formed from sulfates and organic sulfur compounds in the feedstock under anaerobic conditions. As shown, all these operational parameters are in narrow ranges, and this implies the anaerobic digesters were being operated under stable conditions. Utilizing the daily biogas generated for baking injera improves the overall food making process and reduces ・〉ewood consumption by 5.4%. Using Equation (1) and a physical property listed in Table 5, the daily total volumetric flow rate () is found to be 0.74 m3/day.