51results about How to "High arsenic removal efficiency" patented technology

The present invention relates to a method for removing arsenic in arsenic contaminated water, especially for small drinking water systems such as those used in individual homes, rural areas, and small communities, by simply contacting arsenic-contaminated water with an arsenic removal medium. The present invention also relates to the composition of the arsenic removal medium, which comprises particles of calcium carbonate minerals and magnesium carbonate aggregates.

The invention discloses a method for treating wastewater containing trivalent arsenic by utilizing microorganisms. The method comprises the following steps: adding ferrous salt into wastewater to be treated which contains the trivalent arsenic; meanwhile, adding iron-oxidizing bacteria which stays at a growth logarithmic period; adjusting the pH (Potential of Hydrogen) to be 1.6 to 2.8; controlling the temperature to be 25 DEG C to 30 DEG C; uniformly stirring and reacting for 3d to 5d; standing and precipitating the trivalent arsenic in a form of tooeleite; filtering and finishing treatment. A microorganism oxidization method disclosed by the invention can be used for treating the arsenic-containing wastewater with the arsenic content of 3.56g / L to 7.57g / L and adjusting the pH to be 1.6 to 2.8; at room temprature of 25 DEG C to 30 DEG C, the removal rate of the trivalent arsenic within 3d to 4d can reach about 98 percent; the method has the advantages that the raw materials are easy to obtain, the operation is simple and the treatment cost is low; obtained sediment is easy to separate and the arsenic content is high; the stability is good and no secondary pollution is caused.

The invention relates to a normal temperature dearsenifying agent, which consists of active components and a carrier, wherein the carrier is clay; and the active components comprise manganese dioxide and ferric oxide. Particularly, the dearsenifying agent consists of the following components in percentage by weight: 20 to 55 weight percent of manganese dioxide, 10 to 45 weight percent of ferric oxide, and 10 to 35 weight percent of the carrier. Based on the dearsenifying agent, the invention further discloses a method for preparing the dearsenifying agent, and the dearsenifying agent prepared by the method has higher arsenic capacity.

The invention discloses a method for treating wastewater with trivalent arsenic. The method includes simultaneously feeding the to-be-treated wastewater with the trivalent arsenic, iron salt solution and sulfate solution and simultaneously sufficiently colliding the to-be-treated wastewater, the iron salt solution and the sulfate solution with one another to obtain first mixtures; regulating the pH (potential of hydrogen) of the first mixtures until the pH of the first mixtures reaches 1.8-3.0; uniformly mixing the first mixtures with one another at the normal temperature; carrying out reaction; separating precipitates. The method has the advantages that feeding reaction is carried out under the conditions of the temperatures of 25+ / -1 DEG C, the speeds of 600+ / -20 r / min and the pH of 2.4 for 18 min when the arsenic solution with the As <3+> content of 20.5 g / L, the iron salt solution with the Fe <3+> content of 23.0 g / L and the sulfate solution with the SO<4><2-> content of 6.56 g / L are added into 30 mL of deionized water at the speeds of 1.8 mL / min, water hydroxyl sarmientite minerals are good in crystallization, and the As <3+> removal rate is 87.6%; the method for treating the wastewater with the trivalent arsenic is high in arsenic removal efficiency, good effects can be realized, raw materials are low in cost and are easily available, conditions are mild, procedures can be controlled, the precipitates are high in arsenic content, are stable and are easy to separate, secondary pollution can be prevented, and accordingly the method has a broad practical application prospect.