Separation membrane module and fuel vapor processing apparatus equipped with the same

A separation membrane module for separating a specific component from a mixture containing a plurality of components, comprising:

• a plurality of separation stages each including a plurality of hollow fiber membranes arranged in parallel to each other;
• wherein the separation stages are connected in series via at least one connection portion allowing passage of the mixture,
• wherein the mixture is successively introduced into a hollow portion of each hollow fiber membrane of each separation stage, so that the specific component is separated from the mixture as the specific component transmits through each hollow fiber membrane from an interior to an exterior of each hollow fiber membrane,
• wherein the number of the hollow fiber membranes of each separation stage is determined to be larger than the number of the hollow fiber membranes of the other separation stage located just on its downstream side with respect to a direction of flow of the mixture through the separation stages;
• and
• wherein the mixture contains fuel vapor and air, and the specific component is the fuel vapor.

A fuel vapor processing apparatus comprising:

• a canister capable of adsorbing fuel vapor generated in a fuel tank;
• a vapor path communicating between the fuel tank and the canister;
• a recovery path for recovering fuel vapor desorbed from the canister into the fuel tank;
• and
• a pressure reduction unit provided in the recovery path and configured to reduce pressure within the canister for desorbing the fuel vapor from the canister;
• and
• a separation membrane module for separating a specific component from a mixture containing a plurality of components, comprising;
• wherein the separation membrane module separates fuel vapor as the specific component from a fuel vapor containing air, so that the fuel vapor is recovered into the fuel tank in a condensed state, and
• wherein the separation membrane module comprises:
• a plurality of separation stages each including a plurality of hollow fiber membranes arranged in parallel to each other;
• wherein the separation stages are connected in series via at least one connection portion allowing passage of the mixture,
• wherein the mixture is successively introduced into a hollow portion of each hollow fiber membrane of each separation stage, so that the specific component is separated from the mixture as the specific component transmits through each hollow fiber membrane from an interior to an exterior of each hollow fiber membrane,
• wherein the number of the hollow fiber membranes of each separation stage is determined to be larger than the number of the hollow fiber membranes of the other separation stage located just on its downstream side with respect to a direction of flow of the mixture through the separation stages.