CPC C02F 5/02 (2013.01) [C02F 1/52 (2013.01); C02F 2001/5218 (2013.01); C02F 2101/10 (2013.01)] | 6 Claims |
1. A method for removing calcium ions from high concentration organic wastewater, wherein the method comprises the steps of:
(1) introducing inorganic carbon, a seed crystal and high concentration organic wastewater containing Ca2+ into a reactor,
wherein a molar ratio of Ca2+ to inorganic carbon is 1:(3.2-6.2),
wherein the seed crystal in step (1) is biomass with negative potential on a surface, and a particle size of the seed crystal is 0.2 μm-2 mm;
(2) adjusting a hydrogen ion activity α(H+) and ionic strength of the solution in the reactors,
wherein the α(H+) in step (2) is adjusted to 3.16×10−12-6.31×10−9 mol/L, and
the ionic strength after adjusting in step (2) is in a range of 0.3-2 mol/L;
(3) sequentially stirring and precipitating in the reactor to convert Ca2+ in the high concentration organic wastewater into calcium carbonate which is then precipitated for calcium removal,
wherein the precipitating step is followed after the stirring step is stopped.
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