Original Proposal
Methane hydrate formation by using coffee waste
April, 2015
Wenxi Huang
Florida International University
Department of Chemistry and Biochemistry
Advisor: Dr. Rudolf Jaffé
1. Introduction
Natural gas hydrate (NGH) has been considered as a possible alternative for transporting natural gas because of its lower capital cost when comparing with liquefied natural gas (Javanmardi, et al., 2005). Methane is the main component in natural gas (Engineering Data Book, 2004). Therefore, improving the formation of methane hydrate could help to further improve the NGH.
A gas hydrate has a structure like a cage. The hydrogen-bonded water molecules are the line of the cage and the gas molecule is the ‘guest’ that is …show more content…
Methane hydrate has been proved to form faster if increasing the water-gas interface area by agitation of the water (Narita et al., 1996). However, with the appearance of surfactant, the formation rates of gas hydrates can also be increased multiple orders of magnitude (KARAASLAN et al., 2000) even in unstirred system (Zhong et al., 2000). This invention saved the energy costs from stirring hydrate slurry and separation of hydrates from the slurry. However, Wang et al. (2014) found a new way for methane hydrate formation which is using extract of biomass to improve the formation rate. The tea solution has been proved to significantly accelerated (90% saturation uptake in 20 min) kinetics of methane clathrate formation. And by comparing the methane uptake kinetics results between green tea, oolong tea, and black tea (figure 2), they hypothesize the key reactant should be the ingredients (polyphenols and saponins) in tea infusions. And their experiment result (figure 3) confirmed the improvement that anti-oxidant compounds and surfactants like tea polyphenol and tea saponin did for accelerating the hydrate formation and gas storage capacity. Fig. 2 Methane uptake kinetics for pure water, green tea (Longjing), oolong tea (Tieguanyin), and black tea (Yunnan) at 273.2 …show more content…
As well as direct measurement of gas volumes released, capacity was also calculated relative to the pressure change within the reaction vessel. The free space volume of the vessel was obtained by subtracting the sum volume of methane clathrate hydrate and unreacted water. Taking into account nonideality factors, GASPAK v3.41 software (Horizon Technologies, USA) was employed to calculate the methane enclathration capacity, according to the pressure and the temperature. We assume that the liquid and gas phases inside the vessel are exclusively formed from the water and the guest gas, respectively, neglecting any dissolution of the guest gas into the liquid phase and any mixing of the water vapor in the gas phase. The temperature inside the vessel is assumed to be uniform throughout the operation.
Expected outcome 2 The time-volumetric gas capacity chart (figure 6) will show which coffee waste is the most efficient catalyst. Fig. 6 Time-volumetric gas capacity chart for different coffee waste
Methane hydrate formation by using coffee waste
April, 2015
Wenxi Huang
Florida International University
Department of Chemistry and Biochemistry
Advisor: Dr. Rudolf Jaffé
1. Introduction
Natural gas hydrate (NGH) has been considered as a possible alternative for transporting natural gas because of its lower capital cost when comparing with liquefied natural gas (Javanmardi, et al., 2005). Methane is the main component in natural gas (Engineering Data Book, 2004). Therefore, improving the formation of methane hydrate could help to further improve the NGH.
A gas hydrate has a structure like a cage. The hydrogen-bonded water molecules are the line of the cage and the gas molecule is the ‘guest’ that is …show more content…
Methane hydrate has been proved to form faster if increasing the water-gas interface area by agitation of the water (Narita et al., 1996). However, with the appearance of surfactant, the formation rates of gas hydrates can also be increased multiple orders of magnitude (KARAASLAN et al., 2000) even in unstirred system (Zhong et al., 2000). This invention saved the energy costs from stirring hydrate slurry and separation of hydrates from the slurry. However, Wang et al. (2014) found a new way for methane hydrate formation which is using extract of biomass to improve the formation rate. The tea solution has been proved to significantly accelerated (90% saturation uptake in 20 min) kinetics of methane clathrate formation. And by comparing the methane uptake kinetics results between green tea, oolong tea, and black tea (figure 2), they hypothesize the key reactant should be the ingredients (polyphenols and saponins) in tea infusions. And their experiment result (figure 3) confirmed the improvement that anti-oxidant compounds and surfactants like tea polyphenol and tea saponin did for accelerating the hydrate formation and gas storage capacity. Fig. 2 Methane uptake kinetics for pure water, green tea (Longjing), oolong tea (Tieguanyin), and black tea (Yunnan) at 273.2 …show more content…
As well as direct measurement of gas volumes released, capacity was also calculated relative to the pressure change within the reaction vessel. The free space volume of the vessel was obtained by subtracting the sum volume of methane clathrate hydrate and unreacted water. Taking into account nonideality factors, GASPAK v3.41 software (Horizon Technologies, USA) was employed to calculate the methane enclathration capacity, according to the pressure and the temperature. We assume that the liquid and gas phases inside the vessel are exclusively formed from the water and the guest gas, respectively, neglecting any dissolution of the guest gas into the liquid phase and any mixing of the water vapor in the gas phase. The temperature inside the vessel is assumed to be uniform throughout the operation.
Expected outcome 2 The time-volumetric gas capacity chart (figure 6) will show which coffee waste is the most efficient catalyst. Fig. 6 Time-volumetric gas capacity chart for different coffee waste