Supercritical water oxidation system and process using h2o2 as oxidant

Abstract

The invention discloses a supercritical water oxidation system and a supercritical water oxidation process based on H2O2 serving as an oxidizing agent. H2O2 and soft water are boosted and injected into the system after blending, the H2O2 is resolved after preheating, most of oxygen is injected from the upper side of a reactor, supercritical water oxidation reaction between the oxygen and organic waste water is generated but only performed initially due to insufficient oxygen content, few oxygen is dissolved in the soft water, and evaporable water is injected into the water membrane reactor, so that the reactor is protected, a certain amount of oxygen is injected from the side face of the reactor to further oxidize and degrade the organic waste water without enough oxygen, and overheat caused by concentrated release of heat is avoided. A evaporable water boosting branch and an oxygen boosting branch are combined, investment cost is reduced, and system control can be simplified; part of the oxygen is injected from the side face of the water membrane reactor, and oxidative degradation and heat release of the organic waste water are controlled through control of oxygen contents of different reaction areas, so that local overheating of the water membrane reactor is avoided, system startup cost is low, and safety is high.

Description

technical field [0001] The invention relates to the technical field of supercritical water oxidation, in particular to a 2 o 2 A supercritical water oxidation system and process as an oxidizing agent. Background technique [0002] The treatment of high concentration (chemical oxygen demand COD>2000mg / L), toxic and refractory organic wastewater is a recognized technical problem at home and abroad. Traditional organic wastewater treatment technologies, such as physical and chemical treatment technology, biological treatment technology, wet oxidation, incineration, etc., have problems such as high cost, low degradation rate, and easy secondary pollution. Supercritical Water Oxidation (SCWO), as a new technology for treating organic wastewater, is one of the effective methods to solve this problem. [0003] Supercritical water oxidation is a method of "combustion" oxidation of organic matter with air or other oxidants under high temperature and high pressure conditions exc...

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Problems solved by technology

[0005] However, in order to solve the corrosion and salt deposition problems of the reactor, the water film reactor needs to inject a large amount of deionized water as evaporated water from the wall to protect the porous wall, which undoubtedly increases the operating cost of the system

And oxygen accounts for 70% of the operating cost of the system, which is very expensive

The organic waste liquid and the oxidant are injected, mixed and reacted from the top of the reactor, and the supercritical water oxidation reaction is concentrated in the upper part of the reactor, which easily causes the upper part of the reactor to overheat

At the same time, due to the injection of low-temperature evaporated water, the temperature gradient along the axis of the reactor is too large, which may easily cause damage to the porous wall in the reactor.

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