A　small　wastewater　treatment　plant　(WWTP)　failed　to　meet　effluent　requirements　of　the　first-A　discharge　standard　in　China,　with　the　anaerobic/anoxic/oxic　(A/A/O)　process　treating　municipal　and　partial　industrial　wastewater.　Thus　an　A/O　step　feed　process　(Anoxic/oxic/anoxic/oxic/anoxic/oxic)　with　floating　plastic　carriers　in　aerobic　units　was　proposed　to　improve　nutrient　removal　within　the　existing　WWTP.　Emir　main　reform　strategies　were　applied;　(1)　the　original　influent　was　divided　into　three　streams　which　led　into　corresponding　anoxic　units;　(2)　floating　plastic　carriers　were　placed　in　the　second　and　third　oxic　units;　(3)　nitrified　liquid　recycling　was　omitted;　(4)　channel　shapes　and　sizes　were　adjusted　between　adjacent　units　to　prevent　backflow.　After　these　modifications　were　implemented,　the　total　nitrogen　and　phosphorus　concentrations　in　the　effluent　were　reduced　from　20.8　to　14.2　mg/L,　and　from　1.89　to　0.57　mg/L,　respectively.　Moreover,　annual　electricity　consumption　in　the　WWTP　was　reduced　by　245　MW　h　as　a　result　of　these　modifications.　(C)　2012　Elsevier　Ltd.　All　rights　reserved.