High-efficiency energy-saving low-temperature negative pressure deammonia and ammonia recovery system device

Scope of application: high-concentration ammonia nitrogen wastewater, ammonia-containing wastewater, ammonia water recovery, ammonia gas recovery, ammonia nitrogen wastewater recycling

Typical industries: ternary precursors, non-ferrous metals, rare earths, fine chemicals, new energy, coal chemical, petrochemical, metallurgical and other industries

Technical introduction:

Ternary materials, rare earths, non-ferrous metals such as zirconium, niobium and tantalum, as well as coking, chemical, metallurgical and other industries will produce a large amount of high-concentration ammonia nitrogen wastewater. At present, the ammonia removal technology commonly used in this type of ammonia nitrogen wastewater mainly includes air stripping and stripping distillation. The traditional stripping process cannot achieve the efficient removal of ammonia, and the stripping distillation process often has the problem of large steam consumption. At the same time, the two processes have the problems that the ammonia content of the tail gas cannot be stably reached or the ammonia recovery path is single.

The low temperature negative pressure deamination and ammonia recovery system device is a new type of energy-saving and high-efficiency technology developed by our company to solve the problems of high steam consumption and ammonia nitrogen resource recovery in the existing wastewater deamination process; its process flow is:

Ammonia nitrogen-containing wastewater is added with a pH adjuster to adjust the pH of the wastewater to alkaline through a pipe mixer. After the preheater and the water from the tower kettle are exchanged for heat exchange, it enters the low-temperature ammonia removal tower and comes into countercurrent contact with the steam in the tower. Mass and heat transfer is performed in the tower. When ammonia-containing wastewater reaches the bottom of the tower, ammonia nitrogen is converted to ammonia gas removal, and when the bottom of the tower is produced, deammonia wastewater is generated, which is discharged out of the boundary after passing through the tower kettle water pump and preheater. It collects high-concentration ammonia-containing gas, enters the condenser after heat exchange with the reflux liquid, and the ammonia water condensed by the condenser is returned to the low temperature deamination tower through the reflux pump; the heat exchanger increases the temperature of the reflux liquid, thus saving Consumption of deaminated steam reduces the temperature of ammonia-containing gas, thereby reducing the temperature of the condenser and saving investment costs;

The absorption liquid from outside the boundary enters the super ammonia scrubber, circulates in the super ammonia scrubber through a circulating ammonia scrubber, and sucks the high-concentration ammonia gas in the condenser and the gas-liquid separation tank at the inlet to maintain the deamination system in the previous stage. Negative pressure, which reduces the ammonia removal temperature and saves steam consumption. A cooler is installed between the circulating ammonia scrubber pump and the super ammonia scrubber to reduce the temperature of the absorption liquid and improve the absorption efficiency. The condensed gas is sent to the ammonia gas purification tower, which is absorbed by the absorption liquid in the ammonia gas purification tower through the spray circulation pump. The absorption liquid feed port is set on the upper part of the ammonia gas purification tower to ensure that the tail gas is discharged in compliance with the standards. According to different needs, the absorption liquid of the super ammonia scrubber and the absorption liquid of the ammonia gas purification tower can be different media, different concentrations and ratios, so as to achieve high value recovery of ammonia.

Technical advantages:

(1) By providing a super ammonia scrubber, it provides negative pressure to the front-end deamination system, reduces the temperature of the deamination system, saves steam consumption, and improves ammonia removal efficiency; the system steam consumption is 60-90kg per ton of wastewater; deamination efficiency Reach 99.98%;

(2) By setting up a heat exchanger between the low temperature deamination tower and the condenser to exchange heat with the reflux liquid, the temperature of the reflux liquid is increased, the steam consumption of the low temperature deamination tower and the heat exchange area of the condenser are saved, thereby saving investment and land occupation. Area, saving circulating cooling water consumption;

(3) Set up two ammonia recovery points to ensure that the tail gas can still be discharged when the equipment fails or the ammonia concentration is high; and different types and proportions of products can be recovered at the same time according to different absorption liquids; high-value recovery of ammonia nitrogen resources can be realized according to needs ;