Tag:hardness

№7|2011

LAWS, STANDARDS, NORMATIVES

bbk 000000

UDC 628.16(083.75)

Mazaev V. T., Shlepnina T. G.

Assessment of the Sanitary Hazard Degree of Silicon Compounds in Natural and Potable Water

Summary

The survey of literature on the role of silicon in the human body, its toxicokinetics is conducted; the critical analysis of scientific substantiation of hygienic standards of maximum concentration of silicon compounds in natural and potable water is made. The attention is paid to the absence of standards concerning the silicon content in water in the foreign standard specifications because of non-actuality of the problem. It is proposed to cancel the standard of limit content of silicon in the domestic normative base in connection with the absence of its proper reasonableness.

Key words

, , , , ,

 

№7|2019

DRINKING WATER SUPPLY

bbk 000000

UDC 628.16

Gandurina L. V., Kvitka L. A., Shakhgaldian M. K.

Reducing color of natural water with the use of organic coagulants

Summary

The results of studies of the effectiveness of reducing color of low-turbid natural water by filtration with the use of organic coagulants of domestic trademarks: VPK-402, Kaustamin-15 and Biopag are presented. It is shown that the decrease in color of natural waters with organic coagulants occurs mainly due to coagulation processes at low alkalinity close to zero, and chemical interactions of the polyanion of humic acids with the coagulant polycation with alkalinity more than 1.2 mmol-eq/l. It was determined that the optimal doses of organic coagulants increase with a decrease in molecular weight in the series VPK-402 < Kaustamine-15 < Biopag and an increase in alkalinity of the treated water; whereas with an increase in hardness – decrease. In the alkalinity range of 1.2–2 mmol-eq/l the specific consumption of coagulants VPK-402 and Kaustamin-15 increases from 0.04–0.06 to 0.12 mg per degree of initial color while low-molecular Biopag coagulant practically does not change and is 0.09 mg/degree. The dispersion of the formed particles of the suspension increases with a decrease in the hardness of the treated water, an increase in alkalinity and the concentration of low molecular weight fractions of humic acids in water being purified which is accompanied by an increase in color of the purified filtered water. It is shown that the standard decrease in water color below 20 degrees is achieved by removing coagulated particles with a size of more than 0.3 microns in the process of filtration.

Key words

, , , , , , ,

Скачать/download (PDF) free access

 

vstmag engfree 200x100 2

mvkniipr ru

Российская ассоциация водоснабжения и водоотведения

Конференция итог

ecw20 200 300

VAK2