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The performance of three BAFs with zeolite, activated carbon and anthracite media for the treatment of polluted Huaihe raw water were investigated. All three BAFs performed promising permanganate index (CODMn) and ammonia nitrogen (NH4+-N) removal efficiency as well as the turbidity removal was over 60%. Moreover, the CODMn and NH4+-N removal in the three BAFs were affacted by the characteristics of filter media. Activated carbon and anthracite had better CODMn removal than zeolite. Zeolite had the best NH4+-N removal, followed by activated carbon, anthracite was the worst.

As a result of the base-rock corrosion effects and the suspension-carrying capability of polymer in the system of strong base ASP flooding, the concentration of silicon ions in reservoir liquid increases. As the liquid flows into the surface pipelines with tracer heating water injecting, thermodynamics and kinetics conditions change. Suspending power and pH value also decrease. Heavy oil (which content is more than 25%), silts, carbonates and silicates co-deposite, which can cause surface pipelines jamming and even production stopping. Physical or chemistry methods can prolong the rinsing cycles of surface pipelines. Pilot tests indicated that injecting resistance sedimentation agents cost little which had a long rinsing cycle above one year. Hot washing technology had a low cost but with a short rinsing cycle about 2-4 months and the treatment efficiency was easy influenced by the content of oil in blockages. Cavitating water jets technology had good effects and its rinsing cycle were 6 months but cost was high.

Biological Aerated Filter (BAF) has been global applied in secondary and tertiary wastewater treatment process in the past decades. As the increasing application of BAF, it was required to get deeper understanding of the operational discipline, parameter optimization and structural characteristics of BAF to improve the treatment efficiency and to operate stability constantly. In this paper, a physical filtration equation of clean filter bed was established firstly based on an average porosity ratio equation and Kozeny-Carman filtration equation. And then the influence of biological oxidation and biofilm development were introduced, of which the Eckenfelder mode and oxygen transfer were considered, to induce a hybrid physical- biologically equation to describe the headloss development in the BAF.

In order to evaluate the feasibility of the hybrid physical– biologically filtration equation of Biological Aerated Filter (BAF) developed previously, the parameters of the filtration equations were determined through the numerical simulation and experimental fitting, and the empirical formula was carried out finally. The results showed that experimental data were in agreement with the simulated data very well, illustrated that the determined parameter was reasonable and the equation can be used to forecast the headloss development of the tested filter.