Abstract: Adsorption towers are filled with adsorbents that adsorb methane gas in coal mine gas and perform a PSA cycle. For each of adsorption towers, a plurality of different pressure states of the internal pressure of the adsorption tower are set as an intermediate pressure state. As a pressure equalization step, an initial pressure equalization step of transferring the gas in one of the adsorption towers that is in a high pressure state to another one of the adsorption towers that is in an intermediate pressure state, and a final pressure equalization step of transferring the gas in one of the adsorption towers that is in the high pressure-side intermediate pressure state to another one of the adsorption towers that is in the low pressure state are performed.

Abstract: The rate of recovery of a purification target gas from a gas purification apparatus that uses a PSA device is improved, and both a high purity and a high recovery rate are achieved with good power efficiency. The present invention is directed to a gas purification method using the PSA method, in which a carbon molecular sieve having a pore volume, at a pore diameter of 0.38 nm or more, of not exceeding 0.05 cm3/g and a pore volume, at a pore diameter of 0.34 nm, of 0.15 cm3/g or more, in a pore diameter distribution measured by the MP method is used as an adsorbent, and, in an adsorption step, a miscellaneous gas is adsorbed from a source gas by bringing the source gas into contact with the adsorbent for 10 seconds or more and 6000 seconds or less so as to obtain a concentrated methane.

Abstract: The rate of recovery of a purification target gas from a gas purification apparatus that uses a PSA device is improved, and both a high purity and a high recovery rate are achieved with good power efficiency. The present invention is directed to a gas purification method using the PSA method, in which a carbon molecular sieve having a pore volume, at a pore diameter of 0.38 nm or more, of not exceeding 0.05 cm3/g and a pore volume, at a pore diameter of 0.34 nm, of 0.15 cm3/g or more, in a pore diameter distribution measured by the MP method is used as an adsorbent, and, in an adsorption step, a miscellaneous gas is adsorbed from a source gas by bringing the source gas into contact with the adsorbent for 10 seconds or more and 6000 seconds or less so as to obtain a concentrated methane.

Abstract: Adsorption towers are filled with adsorbents that adsorb methane gas in coal mine gas and perform a PSA cycle. For each of adsorption towers, a plurality of different pressure states of the internal pressure of the adsorption tower are set as an intermediate pressure state. As a pressure equalization step, an initial pressure equalization step of transferring the gas in one of the adsorption towers that is in a high pressure state to another one of the adsorption towers that is in an intermediate pressure state, and a final pressure equalization step of transferring the gas in one of the adsorption towers that is in the high pressure-side intermediate pressure state to another one of the adsorption towers that is in the low pressure state are performed.

Abstract: Disclosed is a method for enriching combustible gas, which suppresses the deterioration and pulverization of an adsorbent without extending a period for pressure equalization. The pressure equalization is effected by opening a pressure equalization passage opening/closing valve incorporated in a pressure equalization passage, after completion of adsorption in a first adsorption tower and after completion of desorption in a second adsorption tower connected to the first adsorption tower via the pressure equalization passage.

Abstract: In order to provide a technique for enriching a combustible gas that allows enrichment of the combustible gas to a higher concentration in an efficient manner with minimization of loss of a source material, there are provided an adsorption tower charged with an adsorbent, a feeding/discharging means for feeding a source gas containing a combustible gas and air, a collecting means for desorbing the combustible gas adsorbed to the adsorbent and collecting the desorbed gas, a controlling means for sequentially effecting a combustible gas adsorption process and a combustible gas desorption process, a detecting means for detecting the concentration of the combustible gas in the source gas, and an operation condition setting section for varying an adsorption completion timing for the controlling means to complete the adsorption process, based on the combustible gas concentration detected by the detecting means.

Abstract: A combustible gas enrichment system includes an adsorption unit charged therein with an adsorbent for selectively adsorbing a combustible gas, a source gas feeding means capable of feeding source gas containing the combustible gas into the adsorption unit from the outside, a suctioning means capable of suctioning the gas from the inside of the adsorption unit and a controlling means for executing an adsorption process for feeding the source gas into the adsorption unit for adsorption of the combustible gas to the adsorbent and a desorption process for desorbing the combustible gas from the adsorbent under the suction force of the suctioning means after the adsorption process and taking the desorbed combustible gas to the outside. The controlling means operates the suctioning means such that the suction force of the suctioning means when no desorption process is effected is smaller than the suction force when the desorption process is effected.

Abstract: A combustible gas enrichment system includes an adsorption unit charged therein with an adsorbent for selectively adsorbing a combustible gas, a source gas feeding means capable of feeding source gas containing the combustible gas into the adsorption unit from the outside, a suctioning means capable of suctioning the gas from the inside of the adsorption unit and a controlling means for executing an adsorption process for feeding the source gas into the adsorption unit for adsorption of the combustible gas to the adsorbent and a desorption process for desorbing the combustible gas from the adsorbent under the suction force of the suctioning means after the adsorption process and taking the desorbed combustible gas to the outside. The controlling means operates the suctioning means such that the suction force of the suctioning means when no desorption process is effected is smaller than the suction force when the desorption process is effected.

Abstract: In order to provide a technique for enriching a combustible gas that allows enrichment of the combustible gas to a higher concentration in an efficient manner with minimization of loss of a source material, there are provided an adsorption tower charged with an adsorbent, a feeding/discharging means for feeding a source gas containing a combustible gas and air, a collecting means for desorbing the combustible gas adsorbed to the adsorbent and collecting the desorbed gas, a controlling means for sequentially effecting a combustible gas adsorption process and a combustible gas desorption process, a detecting means for detecting the concentration of the combustible gas in the source gas, and an operation condition setting section for varying an adsorption completion timing for the controlling means to complete the adsorption process, based on the combustible gas concentration detected by the detecting means.

Abstract: Disclosed is a method for enriching combustible gas, which suppresses the deterioration and pulverization of an adsorbent without extending a period for pressure equalization. The pressure equalization is effected by opening a pressure equalization passage opening/closing valve incorporated in a pressure equalization passage, after completion of adsorption in a first adsorption tower and after completion of desorption in a second adsorption tower connected to the first adsorption tower via the pressure equalization passage.