A refinery catalyst sulfur-containing wastewater denitrification process and its application

Abstract

The invention provides an oil refining catalyst sulfide-containing wastewater denitrification technology and application thereof. The technology includes the following steps that oil refining catalyst sulfide-containing wastewater subjected to desulfurization pretreatment is subjected to partial nitrosation treatment and anaerobic ammonia oxidation treatment, and denitrification treatment is finished. The method specifically includes the steps that the pH value of the oil refining catalyst sulfide-containing wastewater subjected to desulfurization pretreatment is controlled to be 8.5-8.8, part of the oil refining catalyst sulfide-containing wastewater is guided into a nitrosation reactor, part of ammonia nitrogen in the oil refining catalyst sulfide-containing wastewater subjected to desulfurization pretreatment is oxidized by ammonia oxidizing bacteria in the reactor to generate nitrite nitrogen, and outflow subjected to wastewater partial nitrosation treatment is obtained, wherein the mass ratio of the nitrogen content of nitrite nitrogen to the nitrogen content of remaining ammonia nitrogen is (0.8-1.32):1; the outflow wastewater is guided into an anaerobic ammonia oxidation and denitrification reactor, and nitrite nitrogen, remaining ammonia nitrogen and nitrate nitrogen are removed by anaerobic ammonia oxidation bacteria and denitrification bacteria in the reactor, wherein the denitrification rate is 90%.

Description

technical field [0001] The invention belongs to the technical field of water treatment, and relates to a bio-based semi-nitrification anaerobic ammonium oxidation denitrification process for high-salt, high-ammonia-nitrogen, sulfur-containing and various heavy metal petroleum refining catalyst wastewater, in particular to a process for denitrification of sulfur-containing wastewater by an oil refining catalyst Nitrogen technology and its applications. Background technique [0002] Petroleum refinery catalyst wastewater has high salt (>15000mg / L), high ammonia nitrogen (>200mg / L), high refractory organic matter (COD>200mg / L), low BOD content (<50mg / L), high sulfate (>800mg / L) L), high pH (>9.0), and containing a variety of heavy metals and a large amount of colloidal substances, it belongs to the special wastewater of petrochemical industry. This kind of wastewater widely exists in all petroleum refining and petrochemical enterprises. Due to the special wat...

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Problems solved by technology

The sewage and wastewater treatment process commonly used in this field is a typical A in the field of water treatment. 2 / O process, but the process has the following problems: (1) due to the high ammonia nitrogen content of petroleum refining catalyst wastewater, the ammonia nitrogen is fully oxidized into nitrate nitrogen, and then denitrification is carried out, and the organic matter that can be effectively used by organisms in the reaction system Therefore, in order to achieve denitrification and denitrification, a large amount of organic matter needs to be artificially added, resulting in the need to supply a large amount of dissolved oxygen (DO) in the process of ammonia nitrogen oxidation, which consumes a lot of energy; (2)A 2 The sulphate content in the effluent of the / O process is high; (3) the alkalinity of the petroleum refining catalyst wastewater is high, which is similar to that of A 2 The pre-denitrification environment of / O process denitrification is contradictory, resulting in low denitrification efficiency. (4) The content of sulfate in petroleum refinery catalyst wastewater is high. 2 The treatment system of the / O process will not only cause waste of energy in the reduction and oxidation units, but also greatly hinder and poison the formation of sludge flocs and the biological activity of bacteria in water treatment.

Currently A 2 In the petrochemical field, the / O treatment process generally only meets the requirement that the effluent ammonia nitrogen does not exceed the standard, but it is still in the state of a large amount of total nitrogen discharge, which is far from the total nitrogen emission control that the petrochemical industry will soon implement.

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