Abstract: Methods for recovering methane gas from natural gas hydrates are provided. A representative method includes the step of adding a gas mixture containing air and carbon dioxide to a natural gas hydrate (NGH), the step of replacing the methane gas with the gas mixture, and the step of decomposition-replacement of methane hydrate.

Abstract: The present invention relates to a method for recovering methane gas from natural gas hydrates. In particular, it includes the step of adding a gas mixture containing air and carbon dioxide to an NGH of deep sea and the step of replacing the methane gas with gas mixture and the step of decomposition-replacement of methane hydrate. In accordance with the present invention, the invention is possible use as a technique for recovery of methane gas in the all-weather to induce replacement reaction using a gas mixture when the temperature of the technology applied is low and to induce degradation of solid methane hydrate by mixing gas when the temperature of the region technique is applied is high. Further, the method makes it possible to reduce costs than using conventional methods because the air is collected directly from the NGH reservoirs and compressed and is injected as a mixture with carbon dioxide and, there is no need to transport the infusion another gas.

Abstract: The present invention relates to a method for recovering methane gas by adding a gas mixture containing N2 and CO2 gases to natural gas hydrate and reacting them. The method for recovering methane gas from natural gas hydrate of the present invention comprises the step of replacing CH4 gas in natural gas hydrate with a gas mixture containing N2 and CO2 gases by adding the gas mixture to the natural gas hydrate. The method for recovering methane gas of the invention assures a recovery rate of CH4 gas much higher than prior art method without dissociating natural gas hydrate layer and utilization of flue gas as a gas mixture containing N2 and CO2 gases, which makes possible its practical application for the production of natural gas in terms of economy and environmental protection.

Abstract: The present invention relates to a method for fabricating an electrochemical sensor which can highly sensibly detect a hydrogen gas by adapting Me4NOH.5H2O as a proton conductor. In the present invention, Me4NOH.5H2O with a high ion conductivity and a reliable thermal stability is adapted as a proton conductor, and a carbon electrode on which a platinum dispersed in an organic solvent is loaded, is used as an anode. It is possible to fabricate a new type electrochemical sensor which adapts an ionic clathrate hydrate capable of reliably detecting hydrogen gas.

Abstract: The present invention relates to a method for recovering methane gas by adding a gas mixture containing N2 and CO2 gases to natural gas hydrate and reacting them. The method for recovering methane gas from natural gas hydrate of the present invention comprises the step of replacing CH4 gas in natural gas hydrate with a gas mixture containing N2 and CO2 gases by adding the gas mixture to the natural gas hydrate. The method for recovering methane gas of the invention assures a recovery rate of CH4 gas much higher than prior art method without dissociating natural gas hydrate layer and utilization of flue gas as a gas mixture containing N2 and CO2 gases, which makes possible its practical application for the production of natural gas in terms of economy and environmental protection.

Abstract: Privacy during communication between video phone terminals is enhanced by eradicating the possibility of eavesdropping through lip reading. Image data on the screen is processed so as not to be recognizable by a third party. Voice data is encrypted and the encrypted data is transmitted and receive. The received data is then decrypted by decoding. The video phone terminal of transmitting side transmits the specially processed entire area or selected area of a picture data so that it will not be recognizable by a third party who does not take part in privacy communication in a video phone terminal of receiving side. The video phone terminal of receiving side receives the processed picture data and recovers the specially processed entire area or selected area of a picture data according to the method processed in video phone terminal of transmitting side.

Abstract: The present invention relates to a method for separation of gas constituents from a multicomponent gaseous mixture employing a hydrate promoter. The method for separation of gas constituents from a multicomponent gaseous mixture includes the steps of reacting an aqueous solution containing a hydrate promoter with a multicomponent gaseous mixture to form a gas hydrate condensed with the gas constituents of high gas hydrate forming power and dissociating a specific gas component from the gas hydrate. In accordance with the present invention, a specific gas component can be seperated from a multicomponent gaseous mixture under a pressure much lower than that of the prior art method, which makes possible its practical application in various industrial areas emitting exhaust gases.

Abstract: The present invention relates to a method for separation of gas constituents from a multicomponent gaseous mixture employing a hydrate promoter. The method for separation of gas constituents from a multicomponent gaseous mixture comprises the steps of reacting an aqueous solution containing a hydrate promoter with a multicomponent gaseous mixture to form a gas hydrate condensed with gas constituents of high gas hydrate forming power and dissociating a specific gas component from the gas hydrate. In accordance with the present invention, a specific gas component can be separated from a multicomponent gaseous mixture under a pressure much lower than that of the prior art method, which makes possible its practical application in various industrial areas emitting exhaust gases.

Abstract: The present invention provides a triple-effect absorption chiller with vapor compression units, where one or more vapor compressors are connected to GM, GH, or evaporator of a conventional chiller, to compress refrigerant vapor from the said generators or evaporator, thereby lowering the GH temperature to a preferable range of below 170° C. The triple-effect absorption chiller of the present invention can be practically applied for lowering the temperature of GH, without the corrosion due to the high temperature of GH.

Abstract: The present invention relates to a method of separating and purifying phenol in a simple and economical manner, by employing a step of adding high pressure carbon dioxide to the aqueous phenol solution to form a solid clathrate of phenol. According to the method of separating phenol of the present invention, phenol can be separated from the highly concentrated phenol solution without employing solvent or post-treatment step, finally to give 100 mole % of a solid phenol and 0.6 mole % of an aqueous phenol solution by employing only one step. Moreover, since the method is carried out at the temperature of below room temperature without excess energy consumption, the separation of phenol can be made in a simple and economical manner.