The effect of Aspergillus niger bioaugmentation on COD and protein removal in domestic wastewater under sewage conditions was assessed. The sewer simulating bioreactor was running at a hydraulic retention time of 17 h, 20°C and pH 7.8 under aerobic condition. When A. niger was bioaugmented, 45 % to 72 % of COD was removed compared to 28 % to 48 % removal of COD in the control at the same period. An overall protein removal of 66 % resulted when A. niger was bioaugmented compared to 29.7 % in the control. Regarding enzymatic activities, we observed that as long as the bioaugmented system biomass concentration was higher than the control, the enzymatic activities were also higher. This research is an initial investigation on wastewater transformation under transitory conditions by A. niger and demonstrated the capacity of A. niger to remove both COD and protein under actual conditions. A. niger bioaugmentation under sewer conditions could be an alternative for wastewater treatment with a valorisation of fungal waste biomass.
This research investigated the effect of mature compost from cassava pulp and swine manure on soil chemical characteristics and growing greenhouse plants i.e., morning glory, Chinese cabbage and Chinese kale. Mature compost with an initial C/N ratio of 30/1 seeded with microbial activator p.d.1 was used in this study. Results revealed that compost in both ground and pelletized forms improved soil quality as indicated by significant increases in TOC content and macronutrients (NO-3-N, available P, and K2O) in soil added with compost compared to control (no compost applied). Plants could use compost in ground form better than pelletized form in which ground compost added at 15.63 ton/ha was the most suitable in growing morning glory, Chinese cabbage, and Chinese kale as indicated by the highest shoot dry weight (1.63, 2.16, and 1.33 g/plant, respectively), and plant circumference (0.56, 3.07, and 0.61 cm/plant, respectively) obtained.
This research investigated the composting process of cassava pulp and swine manure at various initial C/N ratios of 20/1, 30/1, and 40/1 and the effect of microbial activator, p.d.1, on composting process. Compost with an initial C/N ratio of 30/1 seeded with p.d.1 showed the highest maximum temperature (63.5°C), the lowest number of faecal coliform (2.87 Log10 MPN g-1), and the shortest time (around day 42) to reach maturity, suggesting a suitable initial C/N ratio.
Wastewater generated by various processing industries resists conventional wastewater treatment due to its complexity and recalcitrant nature. Ozone is a potential oxidant and is used for various types of wastewater treatment applications. Ozone forms no additional sludge, and aids in the removal of color and chemical oxygen demand (COD). The aim of this work is to investigate ozone application as a pretreatment technique for complex industrial wastewater of Hudiara drain and find an appropriate choice of reaction conditions like ozonation time, pH and temperature necessary to increase ozonation process efficiency. Ozone process efficiency is measured in terms of color and COD removal. Results show that increased ozonation time results in increased color and COD removal due to enhanced mass transfer. A 20-minute ozonation time appears to be optimal for further application. Alkaline pH shows significant effect on the ozonation process. A pH value of 9 is optimal reducing color up to 82% and COD to 67% but the effect of temperature is immaterial. Ozonation process followed pseudo-first order reaction kinetics for color and COD removal.
Metal contents of sediments in Manila Bay - Laguna Lake watershed in the Philippines were measured and detailed horizontal distribution was obtained. The distribution of zinc and lead concentration in Manila Bay clearly shows the effect of anthropogenic contamination and it was explained by the diffusion of lead and zinc rich anthropogenic particles discharged from Pasig River. The sediments in Laguna Lake were mostly natural particulate matters from surrounding mountains and they contained 20 mgPb/kg and 100 mgZn/kg, while the sediment taken at the heavily polluted branches of the Pasig River contained as high as 88 mgPb/kg and 310 mgZn/kg. The lead and zinc concentrations in the sediments of Manila Bay - Laguna Lake watershed were compared with those in the mouth of the Tama River, Tokyo, where the faster deposition of coarser natural origin particles and slower deposition of lead and zinc rich anthropogenic particles determined the sediment concentration. The comparison was also made with Hanoi City, Vietnam. In spite of the difference in time when leaded gasoline was prohibited, the difference in the lead concentrations of roadside deposits and sediments was not obvious in the vicinity of these three target cities. This is probably due to dilution by a large amount of suspended solids conveyed by the Pasig River in the case of the Philippines. Storm water runoff containing roadside deposits and discharge of untreated wastewater were identified as factors increasing zinc and lead concentrations of sediments in receiving waters based on the measurements on roadside deposits and the estimation of the contribution of untreated wastewater.
This study investigated the adsorptive capacity for lead ions of wheat bran (WB), which is a vegetable biomass. The results show that in adsorption by WB, lead ions are competitive with calcium ions. Also, the ability of WB carbonized at 1000°C, to remove lead ions, was higher than that by WB in the low concentration range. The amount of magnesium ions eluted from carbonized WB per unit mass was highest for WB carbonized at 800°C, and was approximately 8 times the amount eluted from WB. Furthermore, the total viable bacteria count after 36 h of WB treatment at 15 - 35°C was 7380 or more. However, the total viable bacteria count after 48h for carbonized WB was 20 - 280, suggesting the possible usage for treatment of drinking water. These results suggest that carbonized WB can be a new adsorbent, have the mineral release ability -- i.e. an adsorbent which removes lead ions which are harmful to people, and releases calcium ions and magnesium ions which are beneficial to people.