Wet oxidation process

The process flow of the wet oxidation system is shown in Figure 3-1, and the specific process is briefly described as follows
.

Figure 3-1 Process flow of wet oxidation system
1-storage tank; 2.

5-vapor-liquid separator; 3-reactor; 4-reboiler;

The waste water is pumped into the heat exchanger by the high-pressure pump through the storage tank, and exchanges heat with the high-temperature oxidation liquid after the reaction, so that the temperature rises close to the reaction temperature and then enters the reactor
.

The oxygen required for the reaction is pumped into the reactor by a compressor

From the economic point of view of wet oxidation process, it is believed that wet oxidation is generally suitable for the treatment of high-concentration wastewater
.

Figure 3-2 analyzes the concentration range of the optimal economic treatment of wastewater by wet oxidation

Figure 3-2 The optimal influent COD range of the warm oxidation system
1～4 are the unit waste water treatment costs corresponding to different ranges of concentration

Figure 3-3 The relationship between influent COD and heat demand

Wet oxidation technology has the advantages of wide application range, thorough decomposition of pollutants, short residence time and less secondary pollution
.

However, it also has some limitations, mainly due to high reaction temperature, high reaction pressure, high requirements for equipment and materials, and low removal efficiency of certain organic substances (such as polychlorinated biphenyls, etc.
)

Another advantage of catalytic oxidation over non-catalytic oxidation is that the use of a suitable catalyst will make non-catalytic oxidation tend to generate the most biodegradable intermediate products (ie, selectivity)
.

Catalytic wet oxidation has been applied on an industrial scale in Europe, the United States, Japan and other countries and regions, and a large number of catalyst patents appear every year.
China began to develop this technology in the late 1990s, and the main research subjects are universities and the Chinese Academy of Sciences.
Waiting for research institutions, but only a few really reach or approach the level of industrial application