An integrated device and method for wet desulfurization and denitrification of ship exhaust gas

Abstract

The invention belongs to the field of waste gas pollution control, and in particular relates to an integrated technology for desulfurization and denitrification of ship waste gas. The device includes a comprehensive washing tower, a dust removal circulation system, a desulfurization circulation system, and a denitrification circulation system; the comprehensive washing tower is divided into three washing areas, which are the first-level washing and dust removal area, the second-level washing and desulfurization area, and the third-level washing and desulfurization area from the exhaust gas inlet to the discharge port. denitrification area; dust removal circulation system includes primary circulation pool, primary circulation pump, solid-liquid separator; desulfurization circulation system includes secondary circulation pool and secondary circulation pump; denitrification circulation system includes regenerative electrolytic cell, fluidized pump, Cooling crystallizer, three-stage circulation pool, three-stage circulation pump. The invention has simple process, stable operation, desulfurization efficiency greater than 98%, and denitrification efficiency greater than 80%. The desulfurization by-product is used as the reducing agent, combined with the electrocatalytic reduction technology to efficiently reduce and regenerate the complex denitrification liquid, and the nitrate content of the waste water meets the requirements of the International Maritime Organization. .

Description

technical field [0001] The invention belongs to the field of waste gas pollution control, and in particular relates to an integrated technology for desulfurization and denitrification of ship waste gas. Background technique [0002] SO emissions from ships 2 and NO x The pollution to the regional environment and the marine atmosphere is becoming more and more serious. For this reason, the International Maritime Organization has formulated an international convention to prevent atmospheric pollution from ships - Annex VI of the MARPOL Convention. The Convention on Sulfur Oxide Emission Limits has been implemented on January 1, 2020, and the implementation technology represented by the exhaust gas cleaning system has been developed. The main methods include seawater method, freshwater + magnesium hydroxide method and magnesium-based seawater method Among them, the magnesium-based-seawater method has gradually become the development trend of ship exhaust gas sulfur oxide emis...

AI Technical Summary

Problems solved by technology

The improvement plan of the research group, CN201310138931.3 discloses a method of using limestone to desulfurize the remaining SO 2 Combining complexation absorption-activated carbon catalytic electrochemical assisted reduction technology to achieve desulfurization and denitrification, but the limestone desulfurization process cannot be applied to ships because the by-product gypsum occupies too large an area, and the catalyst used in this patent is only activated carbon. , the reduction selectivity is not high, prone to side reactions to generate NH 4 + , N 2 O and other substances, resulting in secondary pollution

[0004] To sum up, there is a lack of an integrated system for wet desulfurization and denitrification of ship exhaust gas with high efficiency, reliable operation, low cost, and at the same time ensuring that the waste water is discharged up to the standard.

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