Nitrogen oxide waste gas purification tower is mainly suitable for the purification of electroplating pickling waste gas, which is widely used in solar cell silicon material cleaning production line, chemical industry, machinery, electronics, meters and other industries. After long-term use by users, its purification efficiency can meet the national standards GB16279-1996 "Air pollution comprehensive emission standards" and "odor pollutant emission standards" (GB14554-93) secondary emission standards.
According to the different principles of purification, it can be divided into three categories: catalytic reduction method, absorption and adsorption.
1, catalytic reduction method, the main principle is to reduce the NO× in the exhaust gas into pollution-free N2 under the condition of high temperature and the presence of catalyst, due to the high reaction temperature, while the need for catalyst, equipment investment is large, the operation cost is large.
2, adsorption method, mainly the use of absorbing materials, adsorbents to absorb NO× in the waste gas, due to the small adsorption capacity, so the method is only suitable for low concentration of NO×, small gas treatment.
3, absorption method, water or acid, alkali, salt aqueous solution to absorb nitrogen oxides in the exhaust gas, so that the exhaust gas can be purified. This method has low equipment investment and low operating cost.
Nitrogen oxide exhaust gas purification tower working principle:
Nitrogen oxide NOX exhaust gas under the action of the fan, reach the bottom packing bed, enter the pressure balancing room formed by the internal and external jacket at low speed, the circulation pump is used to transport, countercurrent washing, the exhaust gas is evenly distributed around the PP Terary barbed wreath +PP multi-sided hollow ball alternating packing layer, each showing point contact, arrange "Z or W" irregular route walking, no bias phenomenon, Then with the spiral type high flow rate, not blocking the nozzle, so that the gas-liquid two-phase mixing rate of more than 97%, after the first stage of treatment of the waste gas from the gradual expansion of the deceleration into the secondary packing layer spray function segment, once again make the waste gas to get the gas-liquid two-phase full contact reaction, and then through the dewatering defogging defogging, its tail gas into the next level of acid fog purification tower. In this way, after multiple spraying treatment with indirect and unequal speeds, the gas-liquid two phases can fully contact and absorb until the tail gas meets the secondary emission requirements of the national GB16297-1996 "Comprehensive Emission Standard for Air Pollutants" and the standard requirements of Table 5 and Table 6 of the GB30484-2013 "Battery Industry Pollutant Emission Standard". Finally, it is discharged into the atmosphere through the exhaust pipe.
Nitrogen oxide exhaust gas purification tower performance characteristics:
Using our company's new and efficient proprietary technology equipment, the equipment is improved and developed according to our more than 10 years of similar exhaust gas treatment equipment operating experience, the use of unique technology, the main advantages are as follows:
a. Adopt the turbulent design structure of the air inlet (without this function in the same industry);
b. The use of air inlet practical quick response supplementary device (the same industry does not have this function);
c. The use of jacketed distributed exhaust gas channel (very few in the industry have this function), improve the uniform distribution of exhaust gas, increase the reaction time of exhaust gas flow, and greatly improve the residence time of exhaust gas in the tower;
d. The spray system is fully covered, the gas-liquid phase contact is sufficient, there is no dead Angle, and the reaction is sufficient (the gas-liquid phase contact and reaction time is increased, and the treatment effect is far greater than that of similar equipment of other companies).
(Note: The exhaust gas in the same industry goes directly upward after entering the tower, the distribution is uneven, the reaction is insufficient, and the treatment efficiency is low).
Special spray system, filler and fog collector are adopted, and the nozzles are low pressure, large flow and fine fog nozzles imported from the United States. It is characterized by no clogging, no maintenance and good spray effect. The filler is made of pure PP barbed garland made by our company. Its superior dispersion air flow performance can make the waste gas react more fully with the absorption liquid, and the purification effect is higher. The fog collector is the key part to solve the problem of floating liquid in the purification tower. The fog collector material selected by the company is a fine ball ring with good air permeability, high water blocking efficiency and low airflow resistance produced by the company. Its efficient water collection rate completely solves the problem of floating liquid in the purification tower.
Compact structure, small footprint, corrosion resistance, aging resistance, light weight, easy to install, transport, management, maintenance and other features, purification efficiency is higher and more effective.
Nitrogen oxide exhaust gas purification tower operation and maintenance
1, the purification tower must have a special person responsible for management, set inspection records, and regularly check whether the fan and water pump operate normally every day; Whether the liquid level in the liquid storage tank is within the normal scale; Whether the concentration of NaoH solution is within the prescribed range, if the problem is found, it should be solved in time.
2. Adjust the opening size of the outlet valve of the liquid pump to ensure that the nozzle in the purification tower is covered with water mist to ensure the exhaust gas treatment effect.
3, the concentration of NaoH solution in the liquid storage tank should be maintained in the range of 2-5%, when the concentration is less than 2%, it must be added NaoH solution, the concentration of salt generated by acid and alkali neutralization in the liquid storage tank is higher than 20%, or according to the actual use of regular replacement of the solution, generally completely replace the circulating liquid every month.
4, when replacing the solution, first turn off the pump, drain the saturated solution, and then put the water into the storage tank, and use the pump to cycle for 30 minutes to clean the nozzle and the packing layer.
5, fan, water pump and air valve switching procedures: when starting, first open the air valve, then open the fan, and then open the water pump. When shutting down, turn off the water pump first and then the fan.
6. The dual water pump or dual fan system should switch the water pump or fan every month.
7, according to the use of glass fiber reinforced plastic acid mist purification tower cleaning nozzle, PP filler twice a year, and then regularly replace the nozzle, PP filler, in order to ensure the exhaust gas treatment effect.
8, fiberglass acid mist purification tower air volume regulation is best to use the frequency converter and open air regulation valve.
9, if the weather is cold, if the shutdown, it is best to set PVC pipe insulation or PVC pipe water light, so as to avoid freezing.
10, nitrogen oxide waste gas purification tower equipment neutralization absorption liquid need NaOH and Na2S at the same time to have an ideal treatment effect.
11, the filled NaOH, Na2S to liquid is appropriate, do not use solid content of 98% NaOH or Na2S directly into the equipment liquid storage tank, otherwise it is easy to damage the chemical reaction caused by excessive heat and liquid storage box.
12, in accordance with the first dosing time, according to the production process and production volume, observe the smoke out of the exhaust pipe every day, when the exhaust pipe is seen to produce light yellow gas, it should be added again after 50% of the total amount of the first drug can continue to use (the specific dosage is different due to the amount of waste gas treatment of each project).
13. The liquid in the storage tank must be completely drained after 3 times of circulating dosing, and then it can be continued to be used after re-injection.
14, there is a total dosing box and sub-dosing box, in each sub-dosing box and purification tower dosing, must ensure that the solution temperature is below 50℃, that is, after the total dosing box solution is prepared, especially in hot days, to wait for a period of time, so that the solution temperature is reduced after operation, otherwise the temperature is too high will shorten the dosing pipe, dosing pump service life!
