Supercritical water reaction for sewage treatment test equipment
Supercritical chemical reaction equipment
Supercritical water refers to a dense fluid whose temperature and pressure are higher than its critical point. When the temperature is higher than the critical temperature of water of 374.3 ° C and the pressure is greater than the critical pressure of water of 22.1 Kpa, the properties of water change greatly. Hydrogen bonds in supercritical water are almost absent, and have a very low dielectric constant and good diffusion transfer properties. Many toxic wastes, biological pollution and organic wastewater treatments today do not work with traditional techniques. Supercritical fluids have attracted the attention of scholars from various countries because of their special properties. Some developed countries are competing to develop supercritical water oxidation reaction devices for sewage treatment, and some have realized industrialization. At present, most of China is in the laboratory research stage. The SCWO experimental device produced by our factory is a set of high temperature and high pressure reaction devices developed for laboratory research on supercritical water oxidation reaction.
The flow of the SCWO experimental device is shown in the figure. The working principle is as follows: the wastewater and the hydrogen peroxide are respectively passed through a high-pressure pump, heated to a certain temperature in the preheater, and then enter the mixer, and then enter the reaction tube reaction to reach the reaction time, and then After cooling by the cooler, the pressure is reduced by the back pressure valve, and finally enters the gas-liquid separator to separate the gas phase product and the liquid phase product.
Maximum working pressure of the system: 50MPa;
Maximum working temperature: 600 ° C;
The high-pressure pipeline of the device adopts φ3×1mm stainless steel pipeline, and the low-pressure pipeline adopts φ6×1mm pipeline;
The system installation is carried out according to the process flow chart of the device, with flow chart.
1.Liquid storage tank
Open the top cover of the liquid storage tank, add organic wastewater or hydrogen peroxide into the respective kettles, and screw the lid.
2. Degassing organic wastewater
In order to reduce the experimental error, the organic waste water tank should be effectively and comprehensively degassed. The gas distributor is designed in the kettle to make the nitrogen gas evenly distributed in the kettle body to ensure the removal of oxygen in the organic solution. When degassing, the kettle body The top vent valve should open.
3. Liquid storage tank preheating
If the liquid storage medium is to be preheated, the constant temperature water bath external circulation system can be connected to the preheating sleeve of the liquid storage tank, and the constant temperature water bath user can prepare the preheating temperature through T1 and T2.The operation of the 4.2J-X3.2 / 50 double plunger pump is detailed in the pump manual. The pump pressure overload can be controlled by setting the upper limit of the pole pressure.
5. The operation of the air compressor is detailed in the air compressor instruction manual.
6. Heating and control of sand bath
a) first open the air compressor, adjust the air flow, and blow air into the sand bath;
b) Open the sand bath heating switch.
C) Set the heating temperature of the sand bath with the T6 temperature controller. For details on how to use the temperature controller, see the instructions for using the temperature controller.d). T4 temperature controller is used to measure the reaction temperature, T5 temperature controller and to measure the temperature of the sand in the sand bath;
e) shown. There are two purposes for blowing air compressors. One is to bring the heat of the electric heating tube into the sand bath, and the other is to stir the sand to make the temperature in the sand bath uniform.
Connect the cooler to a valve-controlled tap water source to adjust the water intake to ensure that the T3 measurement temperature is below 100 °C.
8. Control of reaction pressure
The reaction pressure is controlled by a top-loading back pressure valve. The top control pressure can be achieved by manual pump pressurization. To ensure the control accuracy, a certain pressure of gas can be added to the buffer vessel beforehand, and then the pump is used to pump pressurized gas. Control pressure.
9. For the use of gas booster pump, please refer to the instructions for use of gas booster pump.When using a gas booster pump, the pump head of the hydrogen peroxide plunger pump must be adjusted to zero to prevent overpressure of the pump head.