[Claim 1]
An apparatus for producing a chemical, comprising:
a fermentor for housing a feedstock and a culture liquid containing a microorganism capable of producing methane through fermentation from the feedstock,
an external pressure-type membrane separation module for separating the microorganism from the culture liquid to obtain a filtrate and a concentrated liquid,
a supply piping for supplying the culture liquid in the fermentor to the membrane separation module,
a reflux piping for refluxing the concentrated liquid from the membrane separation module into the fermentor, and
a solid matter removal mechanism disposed on the supply piping for trapping a part of the solid matter in the culture liquid, wherein
the membrane separation module comprises a container, a separation membrane housed in the container, a first opening allowing the culture liquid flowing into the container to pass therethrough, and a second opening allowing the concentrated liquid flowing out of the container to pass therethrough, the openings being provided in the container,
the first opening and the second opening are arranged apart from each other in the longitudinal direction of the container,
the first opening and/or the second opening is provided on a side surface of the container, and
an aperture size of the solid matter removal mechanism is 1/3 or less of a smaller one of major axes of the first and second openings provided on the side surface of the container. [Claim 2]
The apparatus for producing a chemical according to claim 1, wherein the aperture size of the solid matter removal mechanism is 0.1 mm or more. [Claim 3]
The apparatus for producing a chemical according to claim 1 or 2, wherein the aperture size of the solid matter removal mechanism is 10 mm or less. [Claim 4]
The apparatus for producing a chemical according to claim 3, wherein the aperture size of the solid matter removal mechanism is 2 mm or less.

[Claim 5]
The apparatus for producing a chemical according to any one of claims 1 to 4, further comprising a solid matter addition piping through which the solid matter trapped by the solid matter removal mechanism is added to the culture liquid in the fermentor. [Claim 6]
A method for producing a chemical by using the apparatus for producing a chemical according to any one of claims 1 to 5, comprising:
a step of flowing a culture liquid into a membrane separation module such that the membrane surface linear velocity v [m3/m2/s] of the culture liquid in the membrane separation module in the longitudinal direction of the container and the smaller one A [m] of major axes of the first and second openings provided on the side surface of the container satisfy v>0.8(2gA(S-1))0.5.
[Claim 7]
A method for producing a chemical by using the apparatus for producing a chemical according to any one of claims 1 to 5, comprising:
a step of directly adding the solid matter trapped by the solid matter removal mechanism to the culture liquid in the fermentor. [Claim 8]
A method for producing a chemical by using the apparatus for producing a chemical according to any one of claims 1 to 5, comprising:
a step of adding the solid matter trapped by the solid matter removal mechanism to the culture liquid in the fermentor through the reflux piping. [Claim 9]
A method for producing a chemical by using the apparatus for producing a chemical according to any one of claims 1 to 5 which further includes a feedstock supply piping connected to the fermentor, comprising:
a step of adding a fermentation feedstock to the fermentor through the feedstock supply piping, and
a step of adding the solid matter trapped by the solid matter removal mechanism to the culture liquid in the fermentor through the feedstock supply piping.