Innovative Method of Utilising Hydrogen Peroxide for Source Water Management of Cyanobacteria

Abstract The treatment and control of cyanobacterial blooms using copper-based algaecides in water reservoirs has historically been used, however, due to the adverse impact of copper on the environment, water authorities have been researching and studying new and innovative ways to control cyanobacterial blooms. Hydrogen peroxide has been investigated as an environmentally friendly alternative and this research aims to determine the impact of water quality on its effectiveness based on the decay characteristics in different water samples. Natural water samples from South Australian reservoirs were used to evaluate hydrogen peroxide decomposition and provide a better strategy for water operators in using it as an algaecide. Our experiments show the dependency of hydrogen peroxide decomposition not only on water quality but also on the initial hydrogen peroxide dose. A higher initial hydrogen peroxide dose can trigger the increase of pH, leading to increased consumption of hydrogen peroxide. In addition, the hydrogen peroxide decomposition is significantly accelerated with the rise of copper concentration in water samples. Moreover, it is found that UV light can also affect the decomposition rate of hydrogen peroxide. The hydrogen peroxide decay is more significant under UV light for the samples with lower hydrogen peroxide concentrations. Our study also shows the impact of DOC on hydrogen peroxide decomposition is not substantial. The study also presents a modelling method to optimise hydrogen peroxide application based on water quality characteristics. Our findings can provide knowledge for the water industry to produce a suitable model which can be used to optimise the application of hydrogen peroxide for the control of cyanobacteria.

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Production of Hydroxyl Radical and Removal of Formaldehyde by Calcined Green Tuff Powder and Tile

10.20944/preprints201905.0155.v1 ◽

2019 ◽

Author(s):

Toyohisa Fujita ◽

Lanyin Zhang ◽

Gjergj Dodbiba ◽

Ji-Whan Anh ◽

Yuezhou Wei ◽

...

Keyword(s):

Hydrogen Peroxide ◽

Hydroxyl Radical ◽

Uv Light ◽

Adsorption Rate ◽

Optimum Temperature ◽

High Adsorption ◽

Hydrogen Peroxide Decomposition ◽

Environmental Cleaning ◽

Peroxide Decomposition ◽

Formaldehyde Adsorption

Wasted Green tuff powder produced by cutting Towada stone is recycled as environmental cleaning material. The optimum temperature for green tuff powder calcination to reduce the hydroxyl radical produced in hydrogen peroxide decomposition with ultraviolet light (UV) and no light. The green tuff calcined at 800 °C shows the large decomposition rate of hydrogen peroxide with no UV light when measured by using ESR. With UV light, the optimum temperature for calcinating the green tuff powder in order to reduce hydroxyl radical is also 800 °C. Next, the powder calcined at 800 °C is used to produce the tile by compression and heating, and then the formaldehyde adsorption rate was measured. The green tuff powder calcined at 800 °C showed a high adsorption rate, similar to that of the activated carbon. The tiles formed at 40 MPa and heated st 1100 °C were the strongest and also adsorbed formaldehyde. The adsorbed formaldehyde on the green tuff tile and powder might have a possibility to decompose by photocatalytic.

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The role of copper ions in hydrogen peroxide bleaching: Their origin, removal, and effect on pulp quality

TAPPI Journal ◽

10.32964/tj11.7.37 ◽

2012 ◽

Vol 11 (7) ◽

pp. 37-46 ◽

Cited By ~ 1

Author(s):

PEDRO E.G. LOUREIRO ◽

SANDRINE DUARTE ◽

DMITRY V. EVTUGUIN ◽

M. GRAÇA V.S. CARVALHO

Keyword(s):

Hydrogen Peroxide ◽

Copper Ions ◽

Peroxide Bleaching ◽

Metals Removal ◽

Peroxide Decomposition ◽

Equipment Corrosion ◽

And Performance ◽

And Control ◽

Main Effects

This study puts particular emphasis on the role of copper ions in the performance of hydrogen peroxide bleaching (P-stage). Owing to their variable levels across the bleaching line due to washing filtrates, bleaching reagents, and equipment corrosion, these ions can play a major role in hydrogen peroxide decomposition and be detrimental to polysaccharide integrity. In this study, a Cu-contaminated D0(EOP)D1 prebleached pulp was subjected to an acidic washing (A-stage) or chelation (Q-stage) before the alkaline P-stage. The objective was to understand the isolated and combined role of copper ions in peroxide bleaching performance. By applying an experimental design, it was possible to identify the main effects of the pretreatment variables on the extent of metals removal and performance of the P-stage. The acid treatment was unsuccessful in terms of complete copper removal, magnesium preservation, and control of hydrogen peroxide consumption in the following P-stage. Increasing reaction temperature and time of the acidic A-stage improved the brightness stability of the D0(EOP)D1AP bleached pulp. The optimum conditions for chelation pretreatment to maximize the brightness gains obtained in the subsequent P-stage with the lowest peroxide consumption were 0.4% diethylenetriaminepentaacetic acid (DTPA), 80ºC, and 4.5 pH.

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Spatial Variation of Water Chemistry in Aries River Catchment Western Romania

Applied Sciences ◽

10.3390/app11146592 ◽

2021 ◽

Vol 11 (14) ◽

pp. 6592

Author(s):

Ana Moldovan ◽

Maria-Alexandra Hoaghia ◽

Anamaria Iulia Török ◽

Marius Roman ◽

Ionut Cornel Mirea ◽

...

Keyword(s):

Heavy Metals ◽

Water Quality ◽

Water Chemistry ◽

Water Samples ◽

Mine Drainage ◽

Pollution Indices ◽

Mining Activities ◽

River Catchment ◽

High Concentrations ◽

The Impact

This study aims to investigate the quality and vulnerability of surface water (Aries River catchment) in order to identify the impact of past mining activities. For this purpose, the pollution and water quality indices, Piper and Durov plots, as well vulnerability modeling maps were used. The obtained results indicate that the water samples were contaminated with As, Fe, Mn, Pb and have relatively high concentrations of SO42−, HCO3−, TDS, Ca, K, Mg and high values for the electrical conductivity. Possible sources of the high content of chemicals could be the natural processes or the inputs of the mine drainage. Generally, according to the pollution indices, which were correlated to high concentrations of heavy metals, especially with Pb, Fe and Mn, the water samples were characterized by heavy metals pollution. The water quality index classified the studied water samples into five different classes of quality, namely: unsuitable for drinking, poor, medium, good and excellent quality. Similarly, medium, high and very high vulnerability classes were observed. The Durov and Piper plots classified the waters into Mg-HCO3− and Ca-Cl− types. The past and present mining activities clearly change the water chemistry and alter the quality of the Aries River, with the water requiring specific treatments before use.

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