Gas separation device

A gas separation device, comprising:

• a plurality of membrane modules connected in parallel to each other, the plurality of membrane modules each including a gas separation membrane configured to reduce a non-hydrocarbon gas in a feed gas containing the non-hydrocarbon gas when the non-hydrocarbon gas is supplied to a primary side through a feed gas line and permeates from the primary side to a secondary side;
• permeate gas lines, which are connected to the plurality of membrane modules, and which are each configured to cause a permeate gas to flow out;
• non-permeate gas lines, which are connected to the plurality of membrane modules, and which are each configured to cause a non-permeate gas to flow out;
• a gas line for regeneration configured to supply, as a gas for regeneration of a second membrane module during non-operation, a permeate gas having permeated through a first membrane module during operation among the plurality of membrane modules to the gas separation membrane of the second membrane module;
• a regeneration valve provided in the gas line for regeneration;
• and
• a supply valve provided in the feed gas line connected to each of the primary sides of the plurality of membrane modules,
• wherein the second membrane module is regenerated with the gas for regeneration supplied by closing the supply valve of the second membrane module to bring the second membrane module into a non-operation state, and opening the regeneration valve.