scholarly journals Determination of the Relaxation Time of Physico-Chemical Characteristics of Water After Cavitation Treatment

2001 ◽  
Vol 14 (5) ◽  
pp. 550-563
Author(s):  
Veronika V. Shelenkova ◽  

The results of hydrodynamic treatment of water in the supercavitation mode are presented. Changes in the physicochemical properties of water (electrical conductivity, pH, oxidation-reduction potential (ORP), oxygen content (OCP), etc.) were revealed, the rational duration of cavitation treatment of water was established, and data on the relaxation of these properties were obtained. At the same time, there is an increase in temperature, pH and electrical conductivity, a decrease in ORP and CRC. The time range with the most intense changes in pH and ORP is 30–90 s. The rate of pH and ORP change in the range of 30–90 s is three and two times higher, respectively, than in the range of 90–300 s. These results correlate fairly well with the results of studies of the effect of ultrasound on water. It was found that the maximum pH value is reached under cavitation action for 180 s. The minimum value of ORP takes at 300 s of cavitation treatment, but remains in the area of positive values. It is shown that during the relaxation time, activated water after treatment for 200 min under the used modes of hydrodynamic cavitation treatment does not return to its original state in all measured parameters

2011 ◽  
Vol 17 (1) ◽  
pp. 107-115 ◽  
Author(s):  
Nada Babovic ◽  
Dejan Markovic ◽  
Vojkan Dimitrijevic ◽  
Dragan Markovic

This paper shows the results obtained in field analysis performed at the Tamis River, starting from the settlement Jasa Tomic - border between Serbia and Romania to Pancevo - confluence of Tamis into the Danube. The Tamis is a 359 km long river rising in the southern Carpathian Mountains. It flows through the Banat region and flows into the Danube near Pancevo. During the years the water quality of the river has severely deteriorated and badly affected the environment and the river ecosystem. In situ measurements enabled determination of physico-chemical parameters of water quality of the Tamis River on every 400 m of the watercourse, such as: water temperature, pH value, electrical conductivity, contents of dissolved oxygen and oxygen saturation. The main reason of higher pollution of Tamis is seen in connection to DTD hydro system. Sampling was performed at 7 points with regard to color, turbidity, total hardness, alkalinity, concentration of ammonium nitrogen, nitrite nitrogen, nitrate nitrogen, iron, chlorides and sulphates in samples. The aim of the present work was to evaluate water quality in the Tamis River taking into account significant pollution, which originates from settlements, industry and agriculture, and to suggest appropriate preventive measures to further pollution decreasing of the river's water.


Author(s):  
David N. Ogbonna ◽  
Sebastine A. Ngah ◽  
Patrick O. Youdeowei ◽  
Matthew E. Origbe

The surface water resources of Bodo/Bonny communities in Rivers State suffers regular pollution of its ecosystem due to increase in crude oil exploration, refining and activities of other industrial establishments operating within the coastal areas of the Ogoniland of the Niger Delta region of Nigeria.  This have resulted in the wide scale contamination of most of its creeks, swamps and rivers with hydrocarbons and dispersant products resulting in the alteration of the ecological integrity of fragile aquatic systems, bioaccumulation of chemical contaminants by zoobenthos, sediment enrichment, and smothering or asphyxiation of the organisms in water by oil coating, thereby causing death. These conditions have resulted in serious threat to public health and the ecosystems. The study was aimed at determining the physico-chemical characteristics of Bodo/Bonny coastal waters impacted by crude oil spills and their effect on the marine ecosystems. Surface water was collected from 5 stations (BBW1, BBW2, BBW3, BBW4 and LFPW5) with LFPW5 serving as control. Physico-chemical parameters were investigated following standard methods. The results of the physicochemical characteristics of the various sampling points in the dry season showed that pH, TDS and Electrical conductivity values showed statistically significant differences at   P < 0.005. pH was slightly acidic in all sampling locations except for the Link fish pond, the values ranged from 6.20–6.40 which was below DPR Limit of 6.5-8.5 for potable water, TDS recorded 43175–57075 mg/L above DPR permissible Limit of 5000mg/L. Electrical Conductivity (EC) values ranged from 54050 -57050 µS/cm. The Dissolved Oxygen, Biological Oxygen Demand, Turbidity, Chloride recorded in this study varied significantly at P< 0.05. Results of the physicochemical parameters of surface water in the wet season fell within the standard limits except for the conductivity that was above the permissible limits. Comparatively the mean pH value of surface river water with Linked fish pond water which served as the control revealed that the Link fish pond water had the highest pH value of 7.9 than the surface river water samples with a pH of 6.4, TDS (60,200 mg/L), Electrical Conductivity (EC) (µS/cm3) followed a similar pattern with the mean EC value of 55,800 mg/L as against 750mg/L for the Link Fish pond water. Temperature recorded 310C as against 300C for the link fish pond while the Salinity (mg/L) of the surface river water was 31.63 mg/L. Dissolved Oxygen was  2.3 mg/L, Biochemical Oxygen Demand values for the surface river water was 0.49 mg/L while the Link fish pond water had 0.3mg/L. These values obtained in this study shows that the spilled oil in the water could impact on species abundance and biomass by depleting and depriving the fishes from available O2 for survival thus resulting in asphyxiation.


Author(s):  
Md. Motaharul Islam ◽  
Mst. Taslema Nasrin ◽  
Md. Mofizul Islam

A research was carried out to assess the suitability of surface water for irrigation purposes. For this reason, 56 samples of surface water were collected from each union of Dinajpur sadar upazilla, Dinajpur. The analysis was included pH, EC, TDS, Ca, Mg, S, P, Na, K, Cl- and HCO3- to evaluate the suitability of surface water for irrigation purposes. Almost all the water samples were within the recommended pH value for irrigation and a great impact on crop production. With respect to electrical conductivity (EC) samples were low to medium salinity. For total dissolved solids (TDS), all samples were considered as freshwater for irrigation. On the basis of Ca, Mg, S, P, Na, K, Cl- and HCO3- all samples could safely be used for irrigation and would not affect the soils.


2019 ◽  
pp. 103-111
Author(s):  
Victoria Abiola Dairo ◽  
Victor Oludare Fagoyinbo ◽  
Godson Mac-tyger

A total of 26 water samples comprising of well, river and borehole waters were subjected to physico-chemical tests to evaluate its quality. The result of the physical characteristics shows that the average pH value, total dissolved solid and electrical conductivity is 4.9, 1027.31mg/L and 1526.92mg/L respectively. Thus, relatively above the desirable limit for drinking water while the ionic dominance of the major cations and anions reveal high concentration of Na+ and Cl- amidst other ions in the order of Na+>Ca2+>Mg2+> K+ and Cl->HCO3- > SO42- respectively wherein the water was classified as belonging to Na-Cl facies and unsuitable for irrigation purpose.


2014 ◽  
Vol 25 (2) ◽  
pp. 75-80 ◽  
Author(s):  
Elisabeta Chirila ◽  
Elena Oancea ◽  
Ioana Adina Oancea

Abstract The purpose of the paper is to present original results concerning characterization of different sea buckthorn (Hippophae rhamnoides L.) extracts and some original dermato-cosmetic products containing these extracts. Aqueous distillate from fruits and leafy branches, aqueous extract from seeds, fresh fruit juice and frozen fruit juice after 2 years of storage, ethanolic extracts of buds have been analyzed for the following parameters: total and organic acidity, oxidability, calcium and magnezium, pH, conductivity, oxidation-reduction potential (ORP). The investigated sea buckthorn extracts have important contribution in care and treatment of skin diseases; during many years of experience in this field great benefits have been observed. Taking into account also the results of previous studies of other researchers we consider that the ORP measurement of cosmetic mixtures could provide objective, cheap and reliable information about antioxidant activity of complex samples.


In previous communications on this subject (20, 21, 22) we described the results obtained when coloured indicators of known physico-chemical properties were injected into individual living cells. Using a modification of the micromanipulator of Chambers (4), we have worked with various unicellular protozoa and egg-cells, and have been able to draw definite conclusions as to the average hydrogen-ion concentration and the average oxidation-reduction potential of the cell interior. Our first communication dealt with the amœba, and we showed that its internal p H was probably in the neighbourhood of 7.6, while its internal r H (oxidation-reduction potential, 5) was between 17 and 19. Both values are near neutrality, so that this cell could be said to be slightly alkaline and slightly on the electronegative or reducing side of oxidation-reduction neutrality. We next extended our investigation to several types of marine egg-cells before and after fertilisation, and during the early cleavage stages. The changes which the internal p H and r H undergo during these ontogenetic events are very small indeed, and the phylogenetic differences, for example, as between the ovum of the polychsete worm and that of the starfish are correspondingly slight. The egg-cell, then, appeared to have a of about 6.6 and an r H of the order of 21 or 22. It was therefore a little on the acid side of acidbase neutrality and a little on the electropositive side of oxidation-reduction neutrality, differing on both these counts from the amœba. The amœba, therefore, has a higher intensity of reduction than the egg-cell.


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