In　limestone-gypsum　wet　flue　gas　desulfurization　process,　the　pH　change　process　of　slurry　in　absorption　tower　has　the　characteristics　of　high　nonlinearity,　large　lag　and　various　disturbances.　According　to　the　process　of　pH　control　in　wet　flue　gas　desulfurization,　a　model　free　adaptive　control　algorithm　based　on　compact　form　dynamic　linearization　(CFDL-MFAC)　is　designed.　Then　the　simulation　is　carried　out　with　Matlab　based　on　hammestein　model　of　slurry　pH　control　system.　It　is　turned　out　that　CFDL-MFAC　algorithm　can　effectively　use　the　input　and　output　data　of　the　pH　control　process　to　realize　the　tracking　control　of　slurry　pH　and　obtain　high　control　accuracy,　which　verifies　the　effectiveness　of　the　method.　Compared　with　PID　control,　CFDL-MFAC　controller　can　not　only　obtain　better　control　effect,　but　also　effectively　suppress　external　disturbance.