With increasing concerns of organic micropollutants, which are not removed by conventional wastewater treatment process, advanced oxidation processes (AOPs) are recently introduced. Among AOPs, electrochemical advanced oxidation processes (EAOPs) have advantages of simple operation and reasonable costs for construction and maintenance. However, low diffusion rate of pollutants from solution to electrode is regarded as a limitation. In this study, hollow fiber type of carbon nanotube (CHF) was fabricated and operated with flow through system to enhance mass transfer rate. The removal efficiency of BPA was achieved in following order: flow through, cross-flow, and batch methods. In addition, rate of removal in flow through system was significantly enhanced, comparing that of cross-flow operation.
In this study the effects of co-digestion of sewage sludge and food waste leachate on the anaerobic digestion efficiencyfrom sewage treatment facilities in S. Korea were investigated. For this study 15 facilities were selected including 9facilities treating sewage sludge only (S-Only) and 6 facilities treating sewage sludge and food waste leachate (S-MIX).The average volatile solid (VS) removal rate of S-Only was 30.7% and that of S-MIX was 45.2%. The COD removalrate of S-MIX (61.3%) was higher than that of S-Only (48.6%). It has been observed that the anaerobic digestion efficiencyof S-MIX was superior to that of S-Only because S-MIX contained more sufficient nutrient with higher VS contents andtotal solid (TS) contents emerging from food waste leachate. Therefore food waste leachate addition in sewage sludgeanaerobic digestion would be the preferred option to treat only sewage sludge.
The strength, water permeability, and photo-degradation efficiency of NOx of porous concrete with a new concept were studied in this paper. The porous concrete was comprised of coarse aggregate of maximum size 40 mm, cement, silica fume, water and air-entraining(AE) water reducing agent. The strength of porous concrete was strongly related to its matrix proportion and compaction energy. An experimental test was carried out to study the parameters of cement proportions and silica fume content for pavement applications of porous concrete which were paving a footpath, a bikeway, a parking lot, and a driveway. The regressed equations of relationships between compressive strength and flexural strength, and coefficient permeability and void ratios were indicated as y=7.69x+71.74 and y=0.42e0.28x. A method of making an air purification-functioning road, which was spraying a mixture of a photocatalyst, cement, and water onto the surface of the road, was suggested.