Research On The Relativity Of Reclrculating Cooling Water Quality Conditions And Bicoides Applied In Biofouling Control

Due to the deficiency of water resources worldwide, refinery wastewater reuse afteradvanced treatment as recirculating cooling water has gained more and more attention. Basedon the problem of biofouling multiply growing in the recirculating cooling water system, thispaper examined the biofouling heterotrophic bacteria number, population structure andadvantages bacteria, and studied the relationship between biocides application and nutrientsystem. And on this basis, the paper had also cleared the effect of oil leak in the recirculatingcooling water system on biocides using. The results showed that: (1) The heterotrophicbacteria quantity, population structure and also the advantage bacteria of biofouling formedunder different nutrient levels were of great differences, so different types biocides should bechose to control the biofouling's growing; (2) With the increasing of water nutrient levels, thebest inactivated concentration and the best detachment concentration of ClO2 increasedgradually; (3)The inactivated concentration of isothiazolinelcetone was not affected by thewater nutrient levels, while the best detachment concentration of isothiazolinelcetonedecreased with the increasing of the water nutrient system; (4) Using scanning electronmicroscopy (SEM), the biofouling space structure, density, thickness and porosity wereobserved in different nutritional system. It found that under low level, the biofouling wasbigger and not very compact. While under high level, the biofouling was smaller and compact.These microscopic structure and feature of biofouling provided a good basis for controllingthe biofouling in the recirculating cooling water system; (5) After oil leaking for 3 days, alongwith the oil leak concentration increased, the DHA of biofouling under different levelsdecreased. Meanwhile, biofouling wet weight, dry weight, volatile biomass and mechanicalstrength also decreased with the increasing of oil content; (6) Oil had some toxic effect onbiofouling, so oil worked together with the biocides control biofouling. However, oil content did not affect the detaching role of biocides.