PURPOSE: To efficiently subject sludge low in VTS to flocculation dehydration treatment by adding an anionic vinyl polymer which is obtained by adding a polyfunctional monomer to all of monomers within a specific range and polymerizing the resulting monomer compsn. to sludge containing inorg. matter of which VTS (ignition loss of evaporation residue) is a specific value or less.
CONSTITUTION: An anionic vinyl polymer obtained by adding 0.0005-0.003wt.% of a polyfunctional monomer to all of monomers and polymerizing the resulting monomer compsn. is added to sludge containing inorg. matter of which VTS is 60% or less to form flocs which are, in turn, dehydrated. When the amt. of the polyfunctional monomer is below 0.0005wt.%, only the effect of the same degree as a polymeric flocculant is obtained and, when the amt. of the polyfunctional monomer exceeds 0.003wt.%, the addition amt. to sludge becomes excessive. The anionic vinyl monomer is prepared as a water in oil type emulsion, for example, by mixing and emulsifying an aq. soln. containing a water-soluble vinyl monomer and an org. solvent containing a hydrophobia surfactant and polymerizing the resulting emulsified mixture. This water in oil emulsion is converted to an oil-in-water type before used.
| JPH1177062 | FLOCCULATION-SEPARATION |
| JP4661998 | Sludge dehydration method |
| WO/2020/031567 | FLOCCULATION AND SEDIMENTATION DEVICE, AND STARTUP METHOD THEREOF |
HASHIMOTO HIRONOBU
OKAJIMA MASAAKI
MACHIDA MASUZO
