Zero-liquid discharge treatment process for fluorescent penetrant testing wastewater

Abstract

The invention provides a zero-liquid discharge treatment process for fluorescent penetrant testing wastewater. According to the invention, concentratedly-collected fluorescent penetrant testing wastewater is subjected to Fenton oxidation, solid-liquid separation and biochemical treatment; meanwhile, oxidized sludge and biochemical sludge are subjected to press filtration to remove dry sludge; press-filtered sewage together with concentratedly-recovered fluorescent penetrant testing wastewater enter the next cycle of zero-liquid discharge treatment for wastewater; thus, resourceful reutilization of the fluorescent penetrant testing wastewater can be realized, and zero-liquid discharge is truly realized. In the zero-liquid discharge treatment process provided by the invention, sulfuric acidor phosphoric acid is adopted in Fenton oxidation for pH value adjustment, and after oxidation is completed, one or more selected from the group consisting of calcium oxide, calcium hydroxide, calciumcarbonate and calcium bicarbonate are adopted for neutralization. Recycle water obtained by using the zero-liquid discharge treatment process provided by the invention has low total ion concentration, and is free of metal corrosivity, especially free of high-concentration chlorine ions with strong metal corrosivity; meanwhile, the zero-liquid discharge treatment process provided by the inventionhas the advantages of simple process, convenient operation, low construction and operation cost, good wastewater treatment effect and great promotion and application values.

Description

technical field [0001] The invention relates to a waste water treatment process, in particular to a zero-liquid discharge treatment process for fluorescence penetrant detection waste water, which belongs to the technical field of industrial waste water treatment. Background technique [0002] Fluorescence penetrant testing is mainly used in non-destructive flaw detection of precision parts, and is widely used in aviation, aerospace, special equipment and other fields. However, fluorescent penetrant testing requires a large amount of detection reagents, and parts cleaning after testing will produce a large amount of high-concentration fluorescent penetrant testing wastewater. [0003] Fluorescence penetrant detection wastewater mainly includes fluorescent agents, surfactants, mineral oil and various chemical additives. The composition is very complex. The COD concentration is often as high as 700-8000mg / L, and the oil concentration is 300-700mg / L. If it is not treated in time...

AI Technical Summary

Problems solved by technology

[0012] First of all, the treatment method proposed by the Eco-environmental Research Center of the Chinese Academy of Sciences involves the use of a specific demulsifier——LWJ demulsifier, which has insufficient demulsification effects on different fluorescent penetrant detection wastewater, thus reducing the applicability; secondly, the ecological environment of the Chinese Academy of Sciences The treatment method proposed by the research center uses hydrochloric acid or calcium oxide as a pH regulator, polyaluminum chloride as an adsorption flocculant, and heating is also required; the former is harmful to the metal surface after a long period of time due to the introduction of chloride ions into the wastewater. Potentially corrosive, therefore, the treated water does not meet the conditions for reuse; while the latter needs to heat the wastewater during the treatment process, the treatment cost is high, and it does not have practical use value. Today, when energy prices are rising, it cannot be achieved. Its claimed cost of 1 yuan;

[0013] In the technical solution provided by Changsha Southern Aerospace Environmental Engineering Co., Ltd., Fenton (Chinese translation is: Fenton) is used as a means of fluorescent penetrant detection of COD removal in wastewater, and at the same time it is combined with reverse osmosis membrane for reverse osmosis treatment, so reverse osmosis will remain Concentrated water, the final result is only to meet the first-level discharge requirements of treated water, but there are still some reverse osmosis concentrated water that cannot meet the required discharge requirements. Therefore, in terms of the wastewater treatment process as a whole, zero discharge cannot be achieved

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