Conclusion: Alum and dried alum have significant bacteriostatic effect in vitro.

Results:It has obvious effect of bacteriostasis on above bacteria.

Polyelectrolytes as coagulant aids lower the required dosages of alum and auxiliary chemicals.

Result: The qualitative detection of Iron salt disaccord with regulations, result in 10 lots Alum from market were disaccord with the standard of Chinese pharmacopoeia, 2005 edition.

The method primarily materializes the paper making sewage with the alumenb and the white sugar, and the processed sewage can be recycled in the production.