Study On Preparation And Application In Treatment Of Petrochemical Wastewater Of Microbial Flocculant

Bioflocculant was prepared firstly. The effect of waterpower condition to flocculationefficiency was investigated and industrial feasibility was analyzed by using the small air floatequipment to simulate float section of industrial wastewater treatment. Flocculability wasenhanced through protoplast amalgamation, the forming and regenerating condition ofprotoplast, the amalgamation with oil degradation strain and the fermentation flocculationcondition were discussed for strain KJ-10 which could produce bioflocculant. At last,bioflocculant industrial feasibility was analyzed.The ingredient analysis for bioflocculant KJ-10 showed that the bioflocculant was milkyfloccule and the extraction efficiency was 6.98g/L. The bioflocculant was of goodthermostability and it could maintain nice flocculation stability in the pH range from 4 to 9.The polysaccharide density of the flocculant was 0.54mg/mL.During the simulation of float section of industrial wastewater treatment by using small airfloat equipment in the laboratory, the flocculation effect was better when wastewater qualitywas acidic or alkaline than neutral. The flocculation activeness increased with the temperaturein the temperature range from10 to 60. The best adding amount of bioflocculant and calciumchloride was respectively 0.04-0.06mL/300mL and 3mL/300mL. The orthogonal experimentresults indicated that the best operating condition was as follow: water temperature 50℃, pH8.0 and the flocculant adding amount 0.06mL.The best forming and regenerating condition for strain KJ-10 was as follow: activating for12 hours in the CM liquid medium with 1% vaccination quantity, processing 12h beforeenzymolysis by adding glycine of 5mol·L^-1, enzyme density 0.1mg·mL^-1, enzymolysis for120 minutes during water bath under temperature of 37 and spreading to regeneration plate which using sucrose as the stabilizer. The protoplast forming and regenerating efficiency couldachieve 93.5% and 20.5% respectively.The amalgamation strain RH-21 was obtained through screening by protoplastamalgamation experiment, of which removing efficiency of COD and the oil degradationeffect is 28.1% and 65.1% respectively. The best fermentation condition for RH-21 was asfollow: organic carbon source sucrose, The carbon nitrogen source combination: Sucrose10g/L, lactose 9g/L, ammonium nitrate 0.8g/L, peptone 0.8g/L, yeast paste 0.2g/L, culturetemperature 30℃, adding amount 0.5%-1%, initial culture liquid pH value neutrality androtational speed 140 r·min-1. The best flocculation condition for RH-21 was as follow:inoculation 0.02-0.07mL/150mL, pH value 5.5-10, and CaCl₂5%. And the flocculation effectbecame better along with the temperature ascension.At last, bioflocculant could be applied inindustryl though analysis.