Cleaning devices and operations for downhole separation in a well

A system comprising:

• a downhole separation system configured to be positioned downhole in a well formed in a subsurface formation, wherein the downhole separation system is configured to receive formation fluid from the subsurface formation and configured to separate formation fluid into a production fluid and a nonproduction fluid, wherein the downhole separation system comprises,
• at least one device to be positioned in an opening of a downhole tubular through which the formation fluid is to be received from the subsurface formation, wherein the at least one device is to filter out at least a portion of solids in the formation fluid from entering the downhole tubular;
• and
• a controller configured to initiate an operation to clean the at least one device using a cleaning fluid;
• and
• wherein the well comprises a multi-bore well, wherein the formation fluid is to be received from the subsurface formation surrounding a first bore of the multi-bore well, and
• wherein the downhole separation system comprises,
• at least one solids separator configured to separate out at least a portion of the solids from the nonproduction fluid;
• a nonproduction fluid pump configured to pump the nonproduction fluid into a second bore of the multi-bore well for disposal into the subsurface formation comprising a downhole disposal location surrounding the second bore;
• and
• at least one solids injector configured to inject the portion of the solids separated out from the nonproduction fluid.