The solutions for acid-base waste gas treatment
Publish Time：2022-11-10 Views：126
Source of acid-base waste gas
In some processes that use nitric acid or mixed acid containing nitric acid, such as aluminum pickling, copper pickling, stainless steel pickling, single crystal silicon and polysilicon pickling, diamond pickling, etc., or where nitrates are decomposed, there are often a large number of NOx exhaust gas (yellow smoke) is discharged. Due to the violent reaction, the instantaneous concentration of NOx is very high.
Acid-base waste gas is generally flammable, explosive, toxic and harmful, insoluble in water, soluble in organic solvents, and difficult to treat. Acid-base neutralization method is commonly used in acid-base waste gas treatment.
Treatment process of acid and alkali waste gas
The main operation method of acid-base waste gas treatment is to introduce acid mist waste gas into the spray tower from the air duct. After passing through the packing layer, the waste gas and the sodium hydroxide absorbing liquid undergo a gas-liquid two-phase full contact absorption and neutralization reaction. After the acid mist waste gas is purified , and then discharged into the atmosphere by the fan after dehydration and defogging by the defogging plate. The absorption liquid is pressurized by the water pump at the bottom of the tower and sprayed down at the top of the tower, and finally refluxed to the bottom of the tower for recycling. The purified acid-base waste gas is discharged after reaching the standard.
Excluded acid mist exhaust gas → enter the air duct → pass through the acid-base exhaust gas spray tower → fan → air duct → discharge up to the standard.
Workflow of the spray tower
The exhaust gas spray tower is operated in gas-liquid countercurrent. The extracted exhaust gas enters the tower BODy from the bottom inlet of the tower, passes through the packing layer from bottom to top, and finally is discharged from the outlet of the top pipe through the anti-corrosion fan. The neutralizing liquid is sprayed evenly into the packing layer through the liquid distributor at the top of the tower, flows down along the surface of the packing layer until the bottom of the tower, and is discharged out of the tower through the pipeline, and is circulated by the anti-corrosion circulating pump. Due to the continuous contact between the rising exhaust gas and the falling absorbent in the packing layer, the concentration of the solute in the rising gas flow is getting lower and lower, and when it reaches the top of the tower, it has reached the absorption requirement and is discharged out of the tower. On the contrary, the concentration of the medium in the descending liquid is getting higher and higher, and when it reaches the bottom of the tower, it reaches the requirements of the process conditions and is discharged out of the tower.
Our spray towers are widely used in the purification and treatment of acid and alkaline waste gas discharged from the chemical, electronics, metallurgy, electroplating, textile (chemical fiber), food, machinery manufacturing and other industries. Such as seasoning food, acid making, pickling, electroplating, electrolysis, storage battery, etc.