To　clarify　the　role　of　solubilized　organics　derived　from　drinking　water　treatment　sludge　(DWTS)　in　the　elimination　of　natural　organic　matter　(NOM)　in　the　DWTS　recycling　process,　a　probe　sonoreactor　at　a　frequency　of　25　kHz　was　used　to　solubilize　the　organics　at　varied　specific　energies.　The　coagulation　behavior　related　to　NOM　removal　in　recycling　the　sonicated　DWTS　with　and　without　solubilized　organics　was　evaluated,　and　the　effect　on　organic　fractionations　in　coagulated　water　was　determined.　The　study　results　could　provide　useful　implications　in　designing　DWTS　recycling　processes　that　avoid　the　enrichment　of　organic　matter.　Our　results　indicate　that　DWTS　was　disrupted　through　a　low　release　of　soluble　chemical　oxygen　demand　(SCUD)　and　proteins,　which　could　deteriorate　the　coagulated　water　quality　under　the　specific　energy　of　37.87-1212.1　kW　h/kg　TS.　The　optimal　coagulation　behavior　for　NOM　removal　was　achieved　by　recycling　the　sonicated　DWTS　without　solubilized　organics　at　151.5　kW　h/kg　IS　specific　energy.　Recycling　the　sonicated　DWTS　could　increase　the　enrichment　potential　of　weakly　hydrophobic　acid,　hydrophilic　matter,　and　＜3　kDa　fractions;　the　enrichment　risks　could　be　reduced　by　discharging　the　solubilized　organics.　Fluorescent　characteristic　analysis　indicated　that　when　recycling　the　sonicated　DWTS　without　solubilized　organics,　the　removal　of　humic-like　substances　was　limited,　whereas　removal　of　protein-like　substances　was　enhanced,　lowering　the　enrichment　potential　of　protein-like　substances.　(C)　2015　Published　by　Elsevier　B.V.