Enhanced deflocculation of dehydrated sludge by rhamnolipid treatment coupled with thermal hydrolysis.

•The demands for sludge reduction is increasing due to strengthening regulations on sludge disposal.•Crude biosurfactant was considered as a cost-effective treatment for the deflocculation of dehydrated sludge.•Rhamnolipids combined with thermal treatment effectively deflocculated the sludge.•Antibiotic resistance was also reduced following rhamnolipid treatment.