Introduction:
pharmaceutical wastewater mainly includes four categories: antibiotic production wastewater, synthetic drug production wastewater, Chinese patent medicine production wastewater, and washing water and flushing wastewater in the production process of various preparations. The wastewater is characterized by complex components, high organic content, high toxicity, deep color and high salt content, especially poor biochemical properties, and intermittent discharge, which is difficult to treat industrial wastewater.
With the development of my country's pharmaceutical industry, pharmaceutical wastewater has gradually become one of the important sources of pollution. How to deal with this type of wastewater is a difficult problem in environmental protection today.
Features
1. High load: COD of pharmaceutical wastewater mainly comes from reactants, solvents, products, and by-products. The COD value is generally in the tens of thousands to hundreds of thousands, and the B/C ratio is <0.1. The biochemical property is poor, and it is difficult to carry out conventional biochemical treatment.
2. High toxicity: The pollutant factors of pharmaceutical wastewater include antibiotics, DMF, THF, acetone, chloroform, and benzene, which inhibit the activity of microorganisms.
3. High salinity: The source of wastewater is raw materials, by-products of synthesis reactions, etc. Cl-, SO42- content >20000 ppm; belong to mixed salt. High salinity will dehydrate, inactivate or even kill microbial cells; exceed the limit of conventional biochemical treatment; increase the density of wastewater and accelerate sludge floating; corrode equipment
4. Complexity: Due to the particularity of the pharmaceutical industry, different production products will lead to great changes in the quality of wastewater.
Solution
Common wastewater treatment process flow:
Antibiotic wastewater treatment process: wastewater→regulation tank→anaerobic tank→contact oxidation tank→dissolved air flotation device→UASB reactor→contact oxidation tank→radial flow sedimentation tank→standard discharge
Synthetic drug production wastewater treatment process: wastewater→bar screen→regulating tank→acidification tank→CASS reaction tank→standard discharge
Traditional Chinese medicine wastewater treatment process: wastewater→bar screen→regulating tank→SBR reaction tank→standard discharge
Introduction to the characteristics of wastewater treatment process:
Saving energy consumption: The amount of oxygen required for biological nitrification and destocking mainly includes the oxygen demand for digestion, endogenous respiration, and degradation of organic matter. The A/O process degrades organic matter while out of stock, greatly reducing oxygen demand, and is an energy-saving biological treatment system.
Good sludge settling performance: In order to maintain a high digestibility, the reaction residence time is longer than the ordinary activated sludge method, microbial endogenous respiration will occur, the sludge growth rate is low, the amount of residual sludge is small, the digestion process is high, and the settling performance it is good.
Save water treatment chemicals: In the A/O process, removing 1mg/l of NO3-N in the destocking process can produce an alkalinity of 3.75mg/l, and the nitrification process of nitrating 1mg/l of NH4-N needs to consume 7.141mg/l of Alkalinity, the alkalinity of the whole system can complement each other, no need to add alkali to neutralize, the organic matter in the garden sewage is used as the hydrogen supplier when it is out of stock, and no external carbon source is needed.
The anoxic tank is in front, and the organic carbon in the sewage is used by denitrifying bacteria, which can reduce the organic load of the aerobic tank. At the same time, the alkalinity produced by the denitrification reaction in the anoxic pool can compensate for the alkalinity demand of the nitrification reaction in the aerobic pool.
After the anoxic tank, the aerobic tank of the A/O process can further remove the organic pollutants left by denitrification and improve the quality of the effluent.