RIGID　algorithm　was　recently　proposed　to　identify　the　contact　state　between　spherical　particles　and　arbitrary-shaped　walls,　demonstrating　significantly　improved　robustness,　accuracy　and　efficiency　compared　to　existing　methods.　It　is　an　important　module　when　coupling　computational　fluid　dynamics　with　discrete　element　model　to　simulate　particle　transport　in　porous　media.　The　procedure　to　identify　particle　and　surface　contact　state　is　usually　time-consuming　and　takes　a　large　part　of　the　CPU　time　for　discrete　element　simulations　of　dense　particle　flow　in　complex　geometries,　especially　in　cases　with　a　large　number　of　particle-wall　collisions　(e.g.　particle　transport　in　porous　media).　This　paper　presents　a　new　version　of　RIGID　algorithm,　namely　ERIGID,　which　further　improves　the　efficiency　of　the　original　algorithm　through　a　number　of　new　strategies　including　the　recursive　algorithm　for　particle-face　pair　selection,　angle-testing　algorithm　for　determining　particle-face　relations　and　the　smallest　index　filter　for　fast　rejection　and　storage　of　time　invariant.　Several　specially　designed　numerical　experiments　have　been　carried　out　to　test　the　performance　of　ERIGID　and　verify　the　effectiveness　of　these　strategies.　Finally,　the　improved　algorithm　is　used　to　simulate　particle　transport　in　a　rock　treated　as　a　porous　medium.　Our　numerical　results　reveal　several　important　flow　phenomena　and　the　primary　reason　for　particle　trapping　inside　the　rock.