Permanganate Preoxidation Research Articles

Laboratory and Full-Scale Plant Studies of Permanganate Oxidation as an Aid in Coagulation

Standard jar tests and full-scale plant studies were conducted to evaluate the effectiveness of permanganate preoxidation as an aid to coagulation-flocculation of surface waters. The results of the Jar tests demonstrated that permanganate preoxidation obviously enhanced the coagulation-flocculation of the studied surface waters. Through full-scale plant studies, the positive effects of permanganate assistance in coagulation-flocculation of surface raters were confirmed by the turbidity reduction of about 4~11 FTU at permanganate dosages of 1~2 mg/L. It was observed that the size of flocs in the reaction tank became bigger if the water was preoxidized with permanganate, lowering the polyaluminium chloride (PAC) consumption by about 36%. In addition. the effectiveness of prechlorination and permanganate preoxidation on assisting in coagulation-flocculation were compared through full-scale studies at a water treatment plant using a shallow lake as its water source. showing that permanganate preoxidation was a more effective means to aid coagulation-flocculatlon.

Quantitative Determination of Murine Dermal Elastic Fibers by Color Image Analysis: Comparison of Three Staining Methods

We compared three different staining methods to determine if the dermal elastic fiber content of the HRS/Skh-1 hairless mouse could be accurately measured by color image analysis. Comparisons were made among Kligman's modification of Luna's mast cell stain for elastin, Unna's orcein stain with or without potassium permanganate preoxidation, and Gomori's aldehyde fuchsin stain with potassium permanganate preoxidation. The color image analysis system could be used to identify and quantify murine dermal elastin fibers in sections stained by all three methods. Gomori's aldehyde fuchsin stain with preoxidation demonstrated twice the content of dermal elastic fibers demonstrated by either Kligman's modification of Luna's mast cell stain or Unna's orcein stain with or without preoxidation. Gomori's aldehyde fuchsin method with preoxidation should be considered the stain of choice for evaluating murine dermal elastic fiber content.

The Impact of Incorporated Organic Matter on the Dewatering Characteristics of Aluminum Hydroxide Sludges

The effects of coagulation of organic matter by alum (as influenced by coagulation pH, dosage, and potassium permanganate preoxidation) on the thickening and dewatering characteristics of aluminum hydroxide sludges were examined. Sludge dewatering characteristics worsened as the specific amount of organic matter incorporated into the sludge floc matrix increased. The observed changes in sludge characteristics were correlated to a decrease in sludge floc size and density that occurred when greater amounts of organic matter were incorporated into the floc structure. Addition of potassium permanganate improved sludge dewatering rates; the dosage required for improvement was a direct function of the amount of organic matter present in the sludge.