The potential for a significant backlog of vessels carrying commodities and other goods increased Thursday as a massive container ship remained stuck in the Suez Canal after running aground Tuesday.

Vessels waiting to pass through the canal or approaching it as of Wednesday included seven crude, 15 refined products, five liquefied natural gas (LNG) tankers and two liquefied petroleum gas carriers, according to research firm Kpler. 

“While attempts to clear the ship from the canal continue, this queue will continue to build,” Kpler said. 

The 1,312-foot-long Ever Given, operated by Taiwan-based Evergreen Marine Corp., had been partially refloated. A salvage team from the Netherlands also was working Thursday to move the ship. 

“We now do not rule out several days of...