Strong-acid wastewater integrated membrane safe and efficient arsenic removal device and process

Abstract

The invention discloses a strong-acid wastewater integrated membrane safe and efficient arsenic removal device and process. The device comprises a membrane contact hydrogen sulfide slow-release gas distribution unit, an immersed membrane solid-liquid separation unit and a membrane contact hydrogen sulfide degassing unit. The membrane contact hydrogen sulfide slow-release gas distribution unit is used for reacting hydrogen sulfide gas with arsenic in the high-arsenic strong-acid wastewater to form arsenic sulfide precipitates by introducing the hydrogen sulfide gas so that arsenic elements in the wastewater are removed. The immersed membrane solid-liquid separation unit is used for carrying out membrane filtration solid-liquid separation on the reacted wastewater, and separated arsenic sulfide precipitates can be collected. The membrane contact hydrogen sulfide degassing unit is used for carrying out hydrogen sulfide degassing treatment on the separated supernatant and removing residualhydrogen sulfide in water through a membrane absorption effect to form sodium sulfide so as to realize recycling of a sulfur element. The integrated membrane arsenic removal process has the technicalcharacteristics of good quality of produced water, high utilization rate of hydrogen sulfide, less tail gas pollution, intensive equipment, lower operation cost and the like, and has good safety andeconomy.

Description

technical field [0001] The invention relates to the technical field of wastewater treatment, in particular to a safe and efficient arsenic removal device and process for strongly acidic wastewater with integrated membranes. Background technique [0002] my country's non-ferrous metal smelting and other industries produce more than 390 million tons of strongly acidic arsenic-containing wastewater every year. The wastewater is mostly treated by lime neutralization-iron salt adsorption precipitation, which can effectively remove heavy metal pollutants such as arsenic in the wastewater while neutralizing the wastewater. However, this method will produce a large amount of arsenic slag which is difficult and expensive to handle. At present, the sulfidation precipitation method is often used in the industry to remove arsenic from waste acid. The sulfide precipitation method uses the precipitation reaction between arsenic and hydrogen sulfide to achieve its efficient removal. Compa...

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Problems solved by technology

Through membrane contact gas diffusion-absorption and removal integrated technology, it is expected to realize the slow release of hydrogen sulfide gas in acidic wastewater and the efficient removal and concentration control of hydrogen sulfide in the effluent, so as to solve the problem of large amount of hydrogen sulfide usage, low utilization rate and tail gas pollution in the traditional arsenic removal process. question

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