In order to find a more practical, effective, low-cost pharmaceutical wastewater treatment methods, will be the existing methods to do a discussion, and from the new ideas, new technologies, this idea, the development of pharmaceutical wastewater treatment methods proposed direction. The current pharmaceutical wastewater treatment methods can be roughly summarized in the following categories.
1. Catalytic oxidation method
Under the action of the catalyst, the organic matter in the wastewater can be oxidized by a strong oxidant decomposition, the double bond in the structure of the organic matter is broken, oxidized by large molecules into small molecules, small molecules are further oxidized into carbon dioxide and water, so that the COD decreased dramatically and the value of BOD/COD increased, increased the biochemistry of wastewater, and the depth of the treatment can be discharged to meet the standards. The wastewater can be discharged to the standard after deep treatment. Catalytic oxidation method to treat pharmaceutical industrial wastewater, can overcome the traditional biochemical treatment of pharmaceutical wastewater effect is not obvious shortcomings, and effectively destroy the organic molecules of the **** conjugate system, to achieve the removal of COD, improve the purpose of biochemistry. Catalytic oxidation method, the choice of catalyst and oxidizer is the key. Selection of suitable catalysts and oxidizers, in the appropriate process conditions for the treatment of wastewater and then after secondary treatment can meet the discharge standards. For example, under the catalytic effect of activated carbon with transition metal oxide catalyst, the use of Cl02 as an oxidizing agent to treat pharmaceutical wastewater, not only low treatment costs, oxidation is much higher than sodium hypochlorite, and will not generate trihalomethanes and other carcinogenic substances.
2. Endoelectrolysis
The principle of endoelectrolysis is the use of iron chips in the iron and graphite components constitute a microelectrolysis of the negative electrode and positive electrode to fill the sewage electrolyte solution, in the acidic medium, the positive electrode produces a new ecological hydrogen with a strong reductive properties, can reduce heavy metal ions and organic pollutants. The negative pole generates ferrous ions with reducing properties. Generated ferrous ions, ferrous ions by hydrolysis, polymerization of hydroxide polymer formed in the form of colloids, which has precipitation, flocculation and adsorption, can form flocs with the pollutants, produce precipitation. The application of endoelectrolysis can remove part of the chromaticity, part of the organic matter in the wastewater, and improve the performance of biochemical treatment of wastewater, increase the removal effect of biological treatment of organic matter. The reaction mechanism is as follows:
Anode (Fe): Fe=Fe2++2eE=-0.44V
Cathode (C): 2H++2e=H2E=0.00V
When there is oxygen: O2+4H+4e=2H2OE=1.23V
O2+2H2O+4e=4OH-E=0.40V
Experimentally, it is proved that the biochemical performance of wastewater is obviously improved after internal electrolysis, which is mainly due to the new ecological hydrogen and ferrous ions produced in the process of internal electrolysis have strong reducing property, which can have redox reaction with the difficult organic matter in wastewater and destroy its chemical structure, thus improving the biodegradation performance. In addition. At the same time as the electrode oxidation and reduction, certain colored substances in the wastewater are also degraded as a result of participating in the redox reaction, thus reducing the chromaticity of the wastewater. Units with pharmaceutical wastewater to be treated can also consult companies with similar wastewater treatment experience at the Sewage Treasure project service platform.
3. Adsorption method
Adsorption method of wastewater treatment is through the activated carbon, sulfonated coal and other adsorbents and adsorbent (solute) and the adsorbent (solute) between the physical adsorption, chemical adsorption, and exchange adsorption of a combination of the role of the pollutants to achieve the purpose of removing. It has the following characteristics:
(1) activated carbon has strong adsorption of organic matter in water;
(2) activated carbon has strong adaptability to changes in water quality, water temperature and water quantity. For the same kind of organic pollutant sewage, activated carbon has better removal effect at high or low concentration;
(3) Activated carbon water treatment device occupies a small area, easy to automatic control, simple operation and management;
(4) Activated carbon also has strong adsorption capacity for certain heavy metal compounds, such as mercury, lead, iron, nickel, chromium, zinc, drilling and so on;
(5 ) saturated carbon can be regenerated and reused without secondary pollution;
(6) useful substances can be recovered, such as the treatment of high concentration of phenol-containing wastewater, regenerated with alkali can be recovered after the phenol sodium salt.
A lot of research and practice has proved that activated carbon is a kind of excellent adsorbent, which has special treatment effect in industrial wastewater treatment. However, due to the limitation of production raw materials and the expensive price, which leads to its popularization and application is limited, and the research of lignite, coke slag, slag and fly ash as adsorbent to treat industrial wastewater has become very active, so whether or not the regeneration of adsorbent can be solved is the key to whether or not the method can be accepted by the manufacturers.
4. Coagulation and precipitation method
Coagulation is an important process in water treatment, through coagulation and precipitation filtration, can significantly reduce the turbidity of the water, chromaticity, removal of suspended solids and impurities in the water. Coagulation process is a very complex physicochemical process, it is in a certain pH, temperature and other conditions, to the wastewater by adding a certain amount of coagulant, through the mixing of sewage and suspended water insoluble and supersaturated substances such as reaction precipitation, so that the wastewater from turbidity to become clear.
The effect of coagulation and coagulant type, impurities in the water, turbidity, PH value, water temperature, the amount of chemicals and hydraulic conditions and other factors are closely related to the coagulant, in which the key to coagulation is to add coagulant chemicals. Coagulant with superior performance is not only good water treatment effect, the cost is also low.
5. Anaerobic biological treatment
Anaerobic biological treatment of wastewater is the use of anaerobic microbial metabolic processes, without the need to increase the oxygen in the case of organic matter into inorganic and a small amount of cellular material, these inorganic substances mainly include a large amount of methane gas and water. This treatment method is a highly efficient and energy-saving treatment process for low-concentration organic wastewater; for high-concentration organic wastewater, it is not only an energy-saving means of treatment, but also a way of production capacity. Anaerobic biological treatment technology is now widely used in the treatment of a variety of industrial wastewater around the world, and it is mainly used in ordinary anaerobic digestion, anaerobic contact process, upflow anaerobic sludge bed (UASB), anaerobic fluidized bed, anaerobic biological carousel and so on. The process combines environmental protection, energy recovery and ecological virtuous cycle organically, can significantly reduce organic pollutants, with anaerobic treatment of high concentration of organic wastewater has a high treatment effect, BOD removal rate of up to 90% or more, COD removal rate of up to 70% -90%, and most of the organic matter is converted into methane.
Wastewater treatment with this method is less expensive than aerobic treatment, high equipment load, covers an area of less, produces less residual sludge, can be directly treated with high concentration of organic wastewater, does not require a large amount of dilution of water, and can be made in aerobic conditions difficult to degrade organic matter degradation, but it is still shortcomings, its initial start-up process is slower, the more sensitive to toxic substances, the operation of the control factors are more complex, and the effluent COD concentration is higher than the aerobic condition, the COD removal can reach 70% -90%, and most of the organic matter into methane. And the COD concentration of the effluent is higher than aerobic treatment, and it still needs subsequent treatment to achieve higher drainage standards. For example, the two-phase anaerobic system composed of UBF acidification reactor with iron chips as packing and UASB studied by Sun Jianhui et al. can treat Zn5-ASA wastewater stably and efficiently. The experimental results showed that the OLR (in terms of COD) of this system was as high as 58.44 and 17.01 kg/(m3.d) for the UBF and UASB when the HRT of the UBF and UASB were controlled at 5.95h and 11.43h, respectively.
The total removal rates of SCOD and BOD5 were about 90% and 95%, respectively, with the advantages of stable system operation and high treatment efficiency. The iron chip filler selected for the UBF reactor in the system can effectively improve the biochemistry of wastewater through the action of microelectrolysis, and the usual alkali adjusting process can be eliminated, which opens up a new way for the treatment of difficult-to-degrade organic wastewater.
Gongyi Yusong Water Supply and Drainage Equipment Factory specializes in the production of a variety of water treatment filter media, water purification chemicals.