[Effectiveness and characteristics of treating algae-laden raw water by stocking silver carp].

To reduce the negative effect of algae on conventional water treatment, a full-scale research of removing algae from algae-laden raw water by stocking filter-feeding silver carp was processed. After the pretreatment in a presedimentation tank with silver carp, the concentration of phytoplankton, the biomass of cyanobacteria and Microsystis flos-aquae in algae-laden raw water with Microsystis flos-aquae its dominant species decreased 61.8%, 76.

[Analysis of the characteristics of corrosion scale in drinking water distribution systems].

Scanning electron microscopy, X-ray fluorescence spectroscopy, X-ray diffraction and X-ray photoelectron spectroscopy were used to analyze the microstructure, chemical composition, crystalline structure and compound constitute of the corrosion scale from cast iron pipe and galvanized steel pipe in drinking water distribution systems. The outer of the corrosion scale was compact, while the inner was porous. Iron was the primary chemical element of the corrosion scale, and the composition of the scale was iron compounds.

[Analysis of influence factors and control methods on iron release phenomenon in drinking water distribution system].

Variation rule of iron in drinking water distribution systems was studied, and it was found that the iron released from the scale to the bulk water was the primary reason for iron overstep. The main chemical composition of the scale in cast iron pipe and galvanized steel pipe was iron in a northern city in China. In the drinking water distribution systems, when the value of dissolved oxygen or chlorine residual was low, the iron release phenomenon was severe.

Iron stability in drinking water distribution systems in a city of China.

A field study on the estimation and analysis of iron stability in drinking water distribution system was carried out in a city of China. The stability of iron ion was estimated by pC-pH figure. It was found that iron ion was unstable, with a high Fe(OH)3 precipitation tendency and obvious increase in turbidity.