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Yunnan is generally famed Kingdom of plants, treasuring the trove of medicines. According to medicinal plants census, the categories of medicinal plants are more than five hundred and with the abundant reserves. There are 63 enterprises in Yunnan which produce medicines using medicinal plants; the Annual output value is more than 3 billion. This makes a great contribution to economy and to Yunnan’s medical and health industries. Meanwhile, hundreds and thousands of organic wastewater discharged every year in the production process. According to the survey, only 30% of enterprises treated wastewater and the wastewater treatment ratio is less than 40%. They generally use normal aerobic oxidation technology, activated sludge treatment or contacting oxidation treatment. The botanicals organic wastewater is with high concentration of COD, generally more than 1000 mg/L, complicated composition of a variety of natural organic compounds, such as sugar, anthraquinones, lignin, alkaloids, tannin, protein, pigment, etc, even containing some toxicity chemical material. This kind of wastewater is regard as hard to treat wastewater.This paper researched the special technologies of selecting, domesticating, strengthening microorganisms naturally existing. According to the properties of wastewater, assort multi-kinds of microorganisms constitute special bacterium groups, dependent on each other, shaping a decomposing chain （food chain） in the sewage treatment facilities and decompose organisms all the time through combination and collaboration in order to achieve high efficiency. The bacterium micelle, shaped by this method with good stability and sedimentation performance, high organic loads and removal rate of pollutants, can remove phosphor and nitrogen at the same time. Meanwhile, the bacterium with good adaptability can survive in the water with some limited toxic and harmful stuff (heavy metal,Cl-, SO42- and etc.). The treatment technical system with the above bacterium and proper operation methods has strong tolerant capacity for the shock loads, quick startup, stable operation and convenient maintenance and management.This 6 month experiment completes a series of cultivation of microorganisms in domesticating, proliferation and etc., on the basis of dominant bacterium acquired through selecting, separating and designing 60 liter anaerobic reactor and 200 liter aerobic experimental tanks. The removal rate of anaerobic unit of COD can reach more than 75% and the removal rate of pollutants is following: COD≥90%, BOD5≥95%, NH4-N≥70%, TP≥95%, if aerobic unit of volume loads is 2.3kgCOD/m3.d, MLSS 1200mg/L. It would satisfy the first standard of GB8978-96. This technique has more obvious superiority than present biological treatment technique for it has high removal rate of pollutants, better efficiency of removing phosphor and nitrogen, high volume loads, little production of sludge and strong tolerance of shock loads.
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