Method and apparatus for continuous production of high-concentrated sodium hypochlorite

Abstract

The invention discloses a method to continual produce high-concentration sodium hypochlorite, which comprises: generating sodium hypochlorite solution, depositing for desalinization, and discharging salt. Wherein, the opposite device comprises a chloridization kettle inserted with two groups of inlet chlorine pipes, a group of subsiders in series, a salt mud tank, and a centrifuge. Wherein, the reaction kettle comprises a reaction area and a deposition area; forcing the qualified sodium hypochlorite supernatant into deposition slot through overflow port. This invention can keep the liquid level invariable and production continual, and has no pollution to environment.

Description

technical field [0001] The invention relates to a production method for continuously producing high-concentration sodium hypochlorite by using sodium hydroxide and chlorine gas. Background technique [0002] Sodium hypochlorite, with the chemical formula NaClO, is a yellow extremely unstable solid, soluble in water, and the aqueous solution is alkaline, and can gradually decompose into sodium chloride, sodium chlorate and oxygen. As a strong oxidizing agent, it is widely used in bleaching pulp and fabrics, as an oxidizing agent and water purifying agent, and is also the main raw material for the production of hydrazine hydrate. [0003] The domestic production of sodium hypochlorite includes the continuous method of introducing foreign devices and technologies, lye chlorination method, bleaching part double decomposition method, tidbit reaction method, electrolysis method, etc. The conventional process of using dilute alkali as raw material and adding chlorine gas to produce...

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Problems solved by technology

[0003] The domestic production of sodium hypochlorite includes the continuous method of introducing foreign devices and technologies, lye chlorination method, bleaching part double decomposition method, tidbit reaction method, electrolysis method, etc. The conventional process of using dilute alkali as raw material and adding chlorine gas to produce low-concentration sodium hypochlorite is to use chlorine gas Put it into a chlorination kettle with a concentration of 25% sodium hydroxide solution, and react at a temperature lower than 15°C to generate sodium hypochlorite and sodium chloride. The available chlorine content of the produced sodium hypochlorite is 60g / l, and the free alkali content It is 145g / l, because the sodium hypochlorite concentration is on the low side, the sodium chloride of by-product can not separate out, exists in the sodium hypochlorite solution, affects the quality and performance of the sodium hypochlorite solution; Simultaneously because this conventional process is intermittent production, the single kettle output of sodium hypochlorite is little, this This process cannot realize large-scale continuous production, and increases labor intensity and increases production equipment

[0004] But unfortunately, before this, no production plant has realized the production of high-concentration sodium hypochlorite in industry, let alone continuous production of high-concentration sodium hypochlorite. technical problem

From the perspective of its reaction mechanism, the conventional single-pipe chlorine method often causes uneven distribution of chlorine gas, resulting in local overchlorination and decomposition of sodium hypochlorite, which has a greater impact on the quality of sodium hypochlorite products. At the same time, high-concentration Sodium hypochlorite, a large amount of by-product sodium chloride will be precipitated, if there is no salt scale removal technology, it will cause blockage of the chlorine pipeline, which cannot guarantee the continuous production of sodium hypochlorite, in addition, a large amount of precipitated by-product sodium chloride If it is not discharged in time, continuous production cannot be guaranteed; moreover, the by-product sodium chloride cannot be effectively used, which will cause environmental pollution and waste of by-product resources

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