Development of Performance Models for Boiler Feed Water Treatment Ion Exchange Facility

The aim of the study was the assessment of corrosivity and aggressiveness for boiler feed water. The negative effects of water corrosivity and aggressiveness may include silting up of the steel water supply system and the destruction of boiler equipment touched or washed by such water. They may cause the whole industrial production system to fail or be destroyed. That is why it was important to reach a high water purification level, including the calculation of water aggressiveness and corrosivity indicators. The carried out test showed that the simple system used before the modernization of the industrial water treatment plant is not sufficient to reach clean and stable water. The authors proposed modernization, including additional processes to improve boiler water quality, and designed new devices for water treatment. As a result of the new idea, groundwater taken as raw water was treated in individual and complex processes, such as pre-aeration, filtration, ion exchange (cation and anion exchange resigns), extra aeration, and extra degassing. The conducted research included chemical analyses of raw and treated water. In the conducted studies, the indirect method of water aggressiveness and corrosivity assessment was applied using mathematical calculation of the Langelier Saturation Index (LSI), the Ryznar Stability Index (RI), the Larson–Skold Index (LI), and the Singley Index (SI). The results proved that the new proposed processes for the boiler feed water treatment station allow reaching a high water quality and low level of water aggressiveness and corrosion.

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Fate of steroid hormone micropollutant estradiol in a hybrid magnetic ion exchange resin-nanofiltration process

Environmental Chemistry ◽

10.1071/en19126 ◽

2019 ◽

Vol 16 (8) ◽

pp. 630

Author(s):

Alessandra Imbrogno ◽

Prantik Samanta ◽

Andrea I. Schäfer

Keyword(s):

Water Treatment ◽

Surface Water ◽

Ion Exchange ◽

Membrane Fouling ◽

Exchange Resin ◽

Environmental Concern ◽

Steroid Hormone ◽

Ion Exchange Resin ◽

Feed Water ◽

Magnetic Ion

Environmental contextContamination of surface water by micropollutants is a major environmental concern because of their high persistence and toxicity. Micropollutants are only partially removed in nanofiltration water treatment systems, encouraging the investigation of more complex systems involving partitioning with membrane materials, organic matter and ion exchange resins. This study elucidates the micropollutant partitioning mechanisms in this complex water treatment system. AbstractThe accumulation of micropollutants, such as steroid hormones, in magnetic ion exchange resin-nanofiltration (MIEX-NF) poses a risk to the environmental contamination of surface water where the treated water is discharged. In this study, the partitioning of the steroid hormone estradiol (E2) with humic acid (HA), MIEX and the membrane is investigated at different feed water conditions (e.g. pH and presence of calcium). The transport and adsorption of E2 in NF is not affected significantly by the E2-HA interaction. Indeed, E2 partitions with HA between 8% and 25% at different pH. This is attributed to the presence of calcium ions, which reduces the number of HA molecules available to interact with E2 molecules. The calcium interference is evident especially at pH>10, where calcite and HA precipitate to result in irreversible membrane fouling. In the hybrid MIEX-NF process, the E2-MIEX interaction occurs at all pH conditions. Approximately 40% of the E2 total mass partitions with MIEX. This is significantly higher than E2 accumulation in NF. Since the partitioning is at least partially reversible, this poses a risk for accidental E2 release into the process streams.

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