Extraction tower processing waste water containing phenol in the process of coke production
Coking wastewater is a kind of ammonia nitrogen and high concentration of organic matter difficult biochemical degradation of organic wastewater, the main pollution of toxic substances for phenolic compounds, coking wastewater biological treatment method in recent years, there are many extraction tower were introduced in this paper to deal with in the process of coke production of phenol wastewater containing phenol GB8978 -
1996 'standard of sewage comprehensive discharge' of the second pollution, a, secondary emission concentration were 0.
Solve the way of wastewater containing phenol in industrial production, the first is actively promote clean production and the reform process, strengthening operation management, try to reduce the discharge production equipment of wastewater containing phenol concentration.
Or will be recycled wastewater containing phenol, in order to reduce waste;
The end of the second is to strengthen management, once the discharge wastewater containing phenol production device, is about to recycle as much as possible, reprocessing, achieve national standards.
Will usually density is above 1000 mg/L, wastewater containing phenol called high concentration phenol wastewater, the wastewater should be recycled after phenol, again for processing;
Concentration is less than 1000 mg/L of wastewater containing phenol, known as the low concentration wastewater containing phenol, often will this kind of wastewater recycling, the post-processing of phenol concentration and recovery;
Concentration of phenol waste water was below 300 mg/L available adsorption, biological and chemical oxidation method for processing after the discharging standard.
with the development of the extraction equipment, as well as the extraction technology in our country want to mature, the present stage phenol wastewater treatment process with extraction, extraction wastewater treatment at home and abroad have been development research, and achieved some results.
Judging from the current situation in our country, there was the main problem is concentrated, the composition of COD and color composition of handling our national conditions cannot be used as liquid CO2 extraction agent, and the commonly used extraction agent is generally need to reverse extraction, extraction solvent after recycling, the extraction solution to deal with.
Domestic wastewater processing by have a common characteristic: a large part of the organic pollutants in waste water as reaction raw materials or products, it is possible to begin from research on extraction, improve the extraction selectivity, make the extraction solution associated with the original production technology.
If it did, solvent extraction method and treatment of high concentration of colored wastewater will be widely used for its economy and practicability.
in the treatment of wastewater containing phenol using pulse vibration of purpose is to make the extraction agent and phenol water produces pulse, make a good contact, prevent emulsion content accumulation in the extraction tower mesh, prevent the sieve pore jams, ensure smooth mesh.
But pulse amplitude to appropriate, amplitude will make liquid flooding, extracting agent and phenol water entrainment each other, a large amount of extraction solvent loss.
The caustic wash tower, the water flooding also affect quality of phenol sodium salt.
Pulse amplitude, general control in 35 mm.
in the extraction process is accompanied by a emulsion content, emulsifying will accumulate on the sieve plate extraction tower, jams mesh, extracting agent and the phenol water is not fully contact, a large number of emulsion also make it easier for oil-water separation, extraction solvent erosion is serious.
Damage emulsifying must get rid of phenol in water hydrophilic substances -
will first phenol water static precipitation in the storage tank, discharge from the bottom of the storage tank tar on a regular basis.
Second will get rid of the phenol water by coke tar filter, its 25 mm to coke, tar phenol water gel, that may be removed.
phenol water processing to appropriate, too much water to produce liquid liquid flooding, general control in 812 t/h.
Extractant recycling in a timely manner regeneration after a period of time.
To pass 75 - extraction agent
85 e hot water, can be emulsified oil emulsion in the extraction solvent, extraction solvent quality to her.
extraction tower DaChu two-phase interface can lead to high extraction oil with water, the impact on the quality of caustic wash tower of phenol sodium salt.
Two phase extraction tower interface is too low will make extractive tower height is too low, influence the extraction efficiency.
So to accurately control interface of two phase extraction tower height, below of extraction tower.