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Impact of Well Remediation Chemicals on Water Quality and Deterioration
Published in Joseph A. Cotruvo, Gunther F. Craun, Nancy Hearne, Providing Safe Drinking Water in Small Systems, 2019
Sodium hexametaphosphate, known as SHMP, is a dry flaky or granular material that is safe to handle and nontoxic. It sequesters calcium/magnesium primarily and iron/manganese dissolved during acidization. It is effectively used at ¼ to ½ pound per gallon of water in the well and suspends mineral deposits, clay, and particulates. It is soluble with adequate mixing, but dissolves very slowly in cold water. It forms a glassy substance when mixed directly with cold water and, as a result, should not be added directly to the well before adequate mixing.
Pretreatment System
Published in Tadahiro Ohmi, Ultraclean Technology Handbook, 2017
In Silicon Valley, California, the coagulation, settling, and filtration method is applied to surface water and underground water is treated with chlorine injection. In general, the cold lime-soda method is not employed because the hardness of the water is low. In Silicon Plain, Texas, the cold lime-soda method is employed for both the surface and underground water, which are high in hardness. This method maintains a high pH of the water, and thus sodium hexametaphosphate is added to prevent scaling in the pipes.
Preparation and characterization of self-suspended CaCO3 nanoparticles derived from scallop shells
Published in Journal of Dispersion Science and Technology, 2023
For dual purpose of improving suspension stability and poor taste, food-grade modifiers possessing strong interaction with the surface of CaCO3 are needed. Sodium hexametaphosphate (SHMP), a common hydrophilic food additive, exists as a linear polymeric structure possessing high surface activity and can interact with the crystal surface to adsorb on it and change its properties. Ren et al.[19] used SHMP to modify starch nanocrystals (SNC) and prepared stable SNC aqueous suspension without changing its original crystalline structure. Tsai et al.[20] found SHMP has a better effect on dispersion of TiO2 nanopowder in water than polyacrylic acid through providing stronger electrostatic repulsion. The structure of SHMP makes an important role in improving modification quality, while the effects of many conditions such as temperature on the structural change of SHMP were paid little attention. Furthermore, scallop shells as one kind of rich renewable resources are one of the global solid waste materials.[21] With much few heavy metal contents, scallop shell is mainly composed of 96 wt.% CaCO3 and a few other elements mainly including Na and Mg, which can be the substitute of limestone and solve bidirectional environmental problems caused by mountainous scallop shells and over-exploitation of limestone.[22–26]
Studies on low-grade coking coal characterisation, flotation response and process optimisation
Published in International Journal of Coal Preparation and Utilization, 2023
Gayatri Hazare, Soumya Sucharita Pradhan, Nilima Dash, Ranjan Kumar Dwari
The batch flotation studies are carried out using a flotation machine (Denver D-12 sub-aeration). The capacity of the flotation cell was 1 liter. About 100 gm of a −0.5 mm fine coal sample is used for the flotation studies. The coal slurry concentration maintained during conditioning is 30% (w/w). The surfactant used in the flotation process is the collector, depressant and frothing agent. Kerosene and diesel are collectors/promoters to make the coal surface hydrophobic. Sodium hexametaphosphate (SHMP) is used as a depressant for mineral particles. Methyl Isobutyl Carbinol (MIBC) is used as a frother. The conditioning time maintained during the coal slurry condition using depressant, collector, and frother are 5, 2 and 1 min, respectively. All the flotation experiments are carried out at pH 7. After the coal slurry condition, the solid concentration is maintained at 10% by adding water to the cell. After conditioning, the flotation is carried out by releasing the air. The froth formed is skimmed off from the top and considered coal concentrate. The un-floated coal that remains in the cell is called tailing. The concentrate and tailings are dried and subjected to ash analysis. The experiments are carried out at different operating parameters, such as by varying collector, frother and depressant dosage.