Environment-friendly high-performance waste water ammonia-removal process and device thereof

Abstract

The invention relates to an environment-friendly high-performance waste water ammonia-removal process, which absorbs ammonia in tail gases to remove ammonia by a dilute acid solution, and leads air containing no ammonia or infinitesimal ammonia to the inlet of a blower for recycled use. The invention further comprises a device which comprises a pH adjusting pond, a sedimentation tank, a waste water intermediate vessel, a waste water feed pump, an ammonia-removal tower, a blower or an induced draft fan, an absorption liquid circulating pump, an absorption liquid circulating groove, a highly dispersing element and a vapor riser, wherein, the absorption liquid circulating pump is connected with the two interfaces on the absorbing section of the ammonia-removal tower to circulate; and the top part and the lower end of the ammonia-removal tower are connected with the blower simultaneously to circulate. The process has the advantages that no tail gas is exhausted while removing ammonia and nitrogen in waste water; and as the temperature of the waste water is kept unchanged, the temperature of the waste water can not decline along with the series increasing of ammonia removing stage by stage during ammonia-removal process, thereby further keeping the ammonia-removal efficiency in a higher range.

Description

technical field [0001] The invention relates to an environment-friendly and efficient waste water ammonia removal process, which can be widely used in the treatment of ammonia nitrogen waste water in petrochemical, chemical fertilizer, textile, pesticide, biological products, catalyst production and other industries, and can also be used in the treatment of municipal sewage and landfill leachate . Background technique [0002] In the traditional ammonia nitrogen wastewater treatment process, air or water vapor is usually selected as the stripping medium, and an empty tower, packed tower or plate tower is used to provide a gas-liquid contact interface to achieve the purpose of removing ammonia from the solution. [0003] The air stripping method is an air stripping process, which is often used to remove ammonia nitrogen in wastewater, that is, the externally supplied gas (carrier gas) is passed into the stripping tower, and the packing filled in the tower is used as a medium ...

AI Technical Summary

Problems solved by technology

[0005] (1) For the occasions where the amount of wastewater treatment is large or the concentration of ammonia nitrogen is high, the design will have to consider increasing the height of the discharge cylinder to 50-60m to meet the requirements of the discharge rate. This will not only increase the investment in the device, but also Increased maintenance difficulty and cost of the device;

[0006] (2) In some areas, due to close proximity to residential areas, or the environmental capacity has reached saturation, the requirements cannot be met at all, and other technologies with higher investment or operating costs have to be sought;

[0007] (3) In the case of high ammonia nitrogen content in wastewater, it is necessary to set up a multi-stage ammonia removal process to meet the discharge requirements. However, due to the temperature drop during the ammonia removal process, the wastewater must be heated to maintain a suitable ammonia removal efficiency. This will not only increase the energy consumption of ammonia removal, but also increase the operating cost

Taking wastewater ammonia nitrogen 20,000-40,000mg / l as an example, if it is treated to ≤15mg / l, the steam consumption will be 350-630kg / t waste water. If the steam price is 100 yuan / ton, the cost of steam alone will reach 35-63 yuan / ton Wastewater, plus chemicals (alkali, flocculant) and power consumption, the cost of wastewater treatment per ton is about 100 yuan

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