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1

Agronomic evaluation of irrigation water on the Southern Buh and Kamianska irrigation systems

Chornyy Sergiy, Isaiva Vera

Journal of Water and Land Development

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2022

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no. 54

77--83

EN

The aim of the research was to study the temporal and spatial dynamics of a set of agronomic criteria for irrigation water in the process of transporting it from the Southern Buh River intake site to the lands of the Southern Buh and Kamianska irrigation systems situated in southern Ukraine. Six stationary research sites for monitoring the quality of irrigation water were established along the route of irrigation water transportation. Determination of agronomic criteria for irrigation water quality was carried out in two terms: at the beginning of the irrigation season, in May, and at the end, in September. The content of cations of sodium, magnesium, calcium, and anions of chlorine, sulphates, carbonates, and bicarbonates was determined. In the field, the pH and electrical conductivity of water, the total salt content, and the total amount of dissolved solids were determined. It is determined that waters have an average level of danger from the point of view of salinisation of soils. This fact leads to a decrease in yield of sensitive to salinity crops (corn, alfalfa and most vegetables). The high content of sodium cations along with the low content of calcium and magnesium cations indicates the danger of degradation of the physical properties of the southern chernozems and the need to use the meliorants containing calcium. There is a high probability of toxic effects on crops caused by sodium cations. At the same time, it is stated that there is no negative effect of chlorine anions on plants.

2

Modeling acid-base transport in hemodialyzers

Pietribiasi Mauro, Leypoldt John K.

Biocybernetics and Biomedical Engineering

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2021

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Vol. 41, no. 3

1150--1161

EN

One important objective of the hemodialysis treatment is the neutralization of interdialytic acid generation by transport of bicarbonate and other buffer bases from dialysis fluid to the patient via the hemodialyzer. Quantification of solute transport in hemodialyzers, in general, employs the concept of dialysance, a parameter that is often constant for given flow conditions, smaller than both the blood and dialysate flow rates, and independent of the solute concentration difference between blood and dialysate. This approach has been applied to bicarbonate transport in hemodialyzers, but such an approach neglects the transport of dissolved carbon dioxide (CO2) between dialysate and plasma, chemical equilibrium between bicarbonate and CO2, and other acid-base chemical reactions within blood. We describe a novel, one-dimensional model of bicarbonate and CO2 transport in hemodialyzers. The model equations were solved numerically and fitted to published data to estimate mass transfer-area coefficients for the relevant chemical species. Base excess in blood was assumed constant in the hemodialyzer. Simulations were performed for a dialysate bicarbonate concentration of 32 mEq/L at constant blood and dialysate flow rates and different plasma bicarbonate concentrations at the inlet of the hemodialyzer, both with and without CO2 transport. In the latter case, the bicarbonate mass transfer-area coefficient was adjusted to achieve the same total carbon dioxide transport. Calculated dialysance for CO2 exceeded the blood flow rate due to its conversion from bicarbonate in the hemodialyzer, and all calculated dialysances varied with inlet plasma bicarbonate concentration. We concluded that acid-base transport in hemodialyzers cannot be universally characterized by dialysances that are always less than the blood flow rate and independent of the concentration difference between dialysate and blood.

3

Experiments on additive desulphurisation by sodium bicarbonate in coal-fuel boiler

Kolat P., Cech B., Vrtek M., Tomasek D.

Chemical and Process Engineering

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2013

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Vol. 34, nr 1

77--86

EN

This paper describes experiments on the application of sodium bicarbonate desulphurisation in the coal-fuel boiler. The boiler has been in operation for several years now and it has refiably fulfilled the original assignment to reduce SO2 emissions from the value of 1200 -1500 mg/Nm3 to 400 mg/Nm3. Higher desulphurisation efficiency is determined only by the ratio of Na/S sorbent dosage. The resulting product of desulphurisation is stored together with fly ash in underground mines, and has no influence on the groundwater. Positive experience of the tests and boiler operation lies in higher reactivity of sodium and sulphur as compared with conventional methods based on limestone. Within the scope of the secondary measures of elimination of sulphur oxides in combustion products, an experimental dry-method desulphurisation of combustion products was performed by blasting an agent containing sodium bicarbonate NaHCO3 (99.6 %) into the flue ways before the electrostatic precipitator in a coal-fuel furnace with the steam output of 220 t/h.

4

Pochodzenie mineralnych wód chlorkowo-sodowych w rejonie Rzeszowa w świetle badań izotopowych(δ18O i δD, δ13C, δ37CL) i chemicznych

Baran A., Pelc A., Chmiel S., Hałas S.

Przegląd Geologiczny

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2012

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Vol. 60, nr 12

657–-664

EN

Several decades ago during exploration for additional resources of tap water a saline water deposit (Cl-Na, J, Fe, B type) has been discovered in the area of Rzeszów hospital park. Nowadays this water is exploited for balneological purposes. In the frame-work of this study for the first time the following stable isotopes: (δ18 i δD, δ13C, δ37Cl) and radiocarbon were determined in order to elucidate the origin of water, its mineralization and quality. Oxygen and hydrogen isotope data leads to conclusion that these waters were formed in a warm pre-Pleistocene period or they are mixture of Miocene seawater with Pleistocene infiltration waters. Carbon isotopic composition (b13= –8.65‰) of bicarbonate is characteristic for deep pore waters occurring in sedimentary rocks, whereas distinctly positive and negative δ37 Cl value rather excludes origin of chlorine ion from an open sea basin. Absence of radiocarbon (in Rzeszów well) indicates no admixture of recent infiltration waters, hence these waters are well preserved from anthropogenic pollution. This is further confirmed by very low concentration of nitrate.

5

Design of the shaft sealing for the bicarbonate suspension mixers

Tomalczyk M., Heim A.

Polish Journal of Chemical Technology

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2006

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Vol. 8, nr 4

45-46

EN

The paper presents a new design of the mixer shaft sealing used in the bicarbonate suspension mixer tanks. The bicarbonate suspension mixing takes place in a cumulative trough and is one of the stages of the soda production process. Initially, the applied shaft sealing tended to wear in a short period of operation, due to the abrasive properties of bicarbonate. The autors proposed a new design of the relieved sealing, the details of which are the content of this paper. The basic assumption of the applied solution is to prevent the penetration of bicarbonate grains into the area of the sealing's working surfaces. The sealing was implemented in 2001 at the Janikowskie Zakłady Sodowe (The Soda Plant) JANIKOSODA S.A.

6

Origin of carbon dioxide and evolution of CO2-rich waters in the West Carpathians, Poland

Leśniak P.

Acta Geologica Polonica

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1998

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Vol. 48, no. 3

343-366

EN

The research was carried out to determine the origin of carbon dioxide and to track the possible isotopic evolution of carbonated waters of the flysch Carpathians. Carbon isotopic composition (-9.2 preomile