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Environmental concerns in the Laguna de Bay basin [Philippines]
1997
Tomboc, C.C. | Francisco, F.F. (Laguna Lake Development Authority, Pasig, Metro Manila (Philippines))
Bioprocess development for biosorption of toxic heavy metals from industrial effluents
1997
Mohd Razman Salim | Zaharah Ibrahim | Abu Bakar baba (Universiti Technologi Malaysia, Skudai Johor Darul Ta'zim (Malaysia). Dept. of Environmental Engineering)
Pollution of the environment by toxic metals arises as a result of human activities such as industrial, agricultural, mine-drainage and sewage disposal. Once in the environment, the metal undergo several forms of transformations. The removal of toxic metal is of great significance from the environmental and industrial point of view. The increased in sound environment and stringent legal requirements has led to the need for cost effective treatment technology for metal pollution control. Biological treatment processes using microbial biomass are known capable of treating industrial waste successfully. The initial aim of the project was to screen a number of metal-tolerant organisms and develop microbial strain capable of detoxification, biosorption and recovery of heavy metals. Due to limited knowledge based studies on several industrial wastes are necessary to determine the potential strains as well as the viable technique to be used in recovery/removal of heavy metals
Show more [+] Less [-]Isolation, identification and bioremediation potential of oil-degrading bacteria from Manila Bay and Pasig River [Philippines]
1997
Dela Cruz, J. | Halos, P.M.
Oil-degrading bacteria were isolated from waters and sediments of the Manila Bay and Pasig River [Philippines]. Five types of bacteria were isolated from Manila Bay and four from Pasig River. The identified crude oil degrading species are Vibrio sp., Alcaligenes sp., Flavobacterium indologenes and Acinetobacter sp. from Manila Bay, and Pseudomonas aeruginosa, Bacillus sp., Micrococcus sp. and Pseudomonas putida from Pasig River. These isolates were identified through morphological and physiological characterization. The bioremediation potential for each of the isolates was assessed. The percentages oil conversion for the bacterial isolates ranged from 2.99 percent - 53.44 percent in one week's time. Alcaligenes sp. exhibited the highest biodegradation potential for all isolates. Statistical analysis revealed that the mean percentages diesel oil conversion by the isolates were significantly higher than their mean percentages crude oil conversion. Pure and mixed cultures did not give significant differences in their mean percentages crude oil conversion
Show more [+] Less [-]Key water quality parameters for sustainable development of Laguna de Bay, Philippines
1997
Barril, C.R. | Tumlos, E.T. (Philippines Univ. Los Banos, College, Laguna (Philippines). Inst. of Chemistry)
Some chemical aspects of melanoidin decolorization by Bacillus subtilis
1997
Rico, L.B. | Bugante, E.C. | Del Rosario, E.J. (Philippines Univ. Los Banos, College, Laguna (Philippines). Inst. of Chemistry)
The natural melanoidin from alcohol distillery biogester effluent and synthetic melanoidin, which was prepared in the laboratory from equimolar amounts of glucose and glycine were decolorized by Bacillus subtilis in shake flash culture. After eight days of fermentation at an initial bacterial level of 2.9 x 10 E 9 cfu/mL, natural melanoidin was 61.1 percent decolorized as measured by absorbance readings at 475 nm: the corresponding decolorization of 0.041 M synthetic melanoidin was 71.9 percent. Gel chromatography through Sephadex G-100 of natural melanoidin before and after microbial action showed molecular weight (MW) values of 35.6 and 33.5 kD, respectively; the corresponding MW values of freshly prepared and decolorized synthetic melanoidin were 42.6 and 37.7 kD, respectively. Values of the instrinsic viscosity, which is proportional to MW, of natural melanoidin before and after decolorization were 18.46 and 16.96 mL/g, respectively; corresponding viscosity values for synthetic melanoidin were 19.77 and 17.16 mL/g, respectively. After bacterial action both natural and synthetic melanoidins showed greater absorbance at 220-350 nm and lower absorbance at greater than 370 nm but showed reduced infrared intensities corresponding to C=O, C=C and O-H stretching vibrations; however the C-O infrared intensity increased. The results suggest partial depolymerization and oxidative degradation of both melanoidins caused by the microorganisms
Show more [+] Less [-]Role of EM (effective microorganisms) in sustainable growth
1997
Ono, H. (Larutan Resources Development Corp., Makati City (Philippines))
Role of on-site wastewater treatment system in improvement of water environment in the Philippines
1997
Rondo, M.
Rapid urbanization of the Philippines, especially of Metro Manila area, has caused serious water pollution. Main causes of this are categorized into industrial wastewater and domestic wastewater, discharged without sufficient treatment. As for industrial wastewater, it is essential to put strict regulations on effluent standards, and for municipalities to keep a regular check to ensure these regulations are observed. Philippine government has been working on the improvement of the legislation and control of industrial wastewater until now. However, from now on, it is vital to put more efforts in getting domestic wastewater treated properly. It is indeed crucial to put the existing sewerage construction plans into practice, but generally, sewerage systems require; 1) long construction period, 2) effective funding, 3) high-density construction, and 4) human resources to run the systems effectively. Meanwhile, on-site waste water treatment tanks, or what we called purifiers, can play an important role in controlling the pollution of water environment, and they will serve to complement the sewerage system even after the completion of construction. Small-scale on-site wastewater treatment tanks, or small-scale purifiers, developed and used in Japan especially in developing countries, not only in the scope of environmental conservation but also from the viewpoint of utilizing the economic resources in the private sector
Show more [+] Less [-]Investigations on the adsorption and degradation of different polar organic compounds in test filter systems
1997
Knepper, T.P. | Wilken, R.D. (ESWE-Inst. for Water Research and Water Technology, Sohnlenstrasse 158, C5201 Wiesbaden (Germany))
Test filter systems are quite helpful to study the persistence of organic compounds in order to give hints for a better remediation of the environment. Therefore special test filters are used in the chemical industry in Germany for more than 20 years in order to determine the microbial bad degradable parts of the dissolved organic carbon (DOC) in the sewage outlets. These test filters can be considered as biological active fixed bed reactors which enable to simulate the biological degradation of organic compounds during an underground passage. It was shown by different investigations, that these test filter systems are well suitable for their expected tasks by determining group parameters. While looking for single compounds they were proven to be such good model systems. For good degradable compounds as e.g., 6-(methyl (phenylsulfonyl) amino)-hexanoic acid (HPS) it could be shown that these substances are microbially degraded on the test filter systems, while the more stable compounds, and an important example for that in Germany is naphthalene-1,5-disulfonic acid, showed a total different behavior. Therefore, the elimination of e.g. napthalene-1,5-disulfonic acid was investigated utilizing labscale filters containing Siran (porous, sintered glass) and activated carbon as support materials for bacteria. However, the different adsorption capacities of activated carbon and Siran had large effects on the measured substrate concentration. Thereby the test filter being run with Siran glass showed to be suitable for modeling the degradation behavior of single compounds during the underground passage. It can be concluded that those test filters can be utilized for studying organic compounds on their behavior as being relevant for water works by means of bad microbial biodegradability
Show more [+] Less [-]Review of the biological studies on Laguna de Bay [Philippines] in relation to aquatic pollution
1997
Guerrero, R.D. III (Philippine Council for Aquatic Marine Research and Development, Los Banos, Laguna (Philippines))
Laguna de Bay is the largest freshwater body in the Philippines with multiple-use. The primary use of the lake is to serve as the future domestic water supply at Metro Manila. The biota of the lake consists of 25 species of fish, 24 species of zooplankton, two species of shrimps, 6 species of mollusks, 42 species of aquatic macrophytes and 154 species of algae. A total of 60 mesophilic anaerobic and facultative anaereobic bacteria and 453 bacterial strains belonging to 22 genera have been identified. A review of 12 papers dealing with biological studies on Laguna de Bay in relation to aquatic pollution is presented. Studies on the impact of heavy metal, pesticide and thermal pollution on the biota of the lake have been sporadic and cursory. There is need for a more comprehensive and systematic monitoring of the lake's pollutants to provide time-series for pollution abatement
Show more [+] Less [-]Biological nutrient removal in suspended growth system
1997
Wisjnurapto, IR.
A series of experiments on biological nutrient removal using suspended growth bioreactor with a various reactor configuration have been conducted during the last five years. The first configuration applied a contact stabilization flowed by a denitrification processes in two sludge system. The two sludge systems mean that the aerobic sludge is recirculated in the aerobic circuit, and the anaerobic sludge is recirculated in the anaerobic circuit. The second configuration was conducted in a contact stabilization and denitrification processes in a one sludge system. The one sludge system meant that there are no separation between aerobic and anaerobic sludge; the aerobic and anaerobic processes are in the same circuit and all sludge are recirculated in the same circuit. The third configuration was performed in anaerobic-aerobic-anaerobic reactors and ended by the clarifier to clarify the biosludge before recirculated to the head of the circuit. This configuration was also using a one sludge system. In those three configurations, the hydraulic detention time in the reactors were varied from 2 to 6 hours, and the sludge age from 2 to 15 days. The results showed that the first configuration gave a very high performance in carbon and nitrogen removal. In terms of TOC [total oxygen concentration], the carbon removal achieved up to 92 percent or in terms of total COD [carbon oxygen demand] up to 80 percent, and 97 percent for total nitrogen removal. On the other hand, the phosphorus removal was only limited to the amount required for cells metabolism. More carbon removal were observed in the second configuration (94 percent of total COD) but less total nitrogen were removed (93), however, phosphorus were removed significantly (up to five times of the cells metabolism requirement). The best results in those three nutrients removal was achieved in the third configuration. No less than 95 percent of total COD and 96 percent of nitrogen removal were noticed, and phosphorus were removed at the level of more than six times of the cells metabolism requirement. The experiments concluded that the phosphorus removal was conducted by the aerobic microorganisms which are alternately treated in aerobic-anaerobic conditions. The degree of removal depended on how long the microorganisms were put in the aerobic and anerobic conditions. If the anaerobic condition was too long, the microorganisms would die, and no phosphorus removal took place. If it was too short, the removal would be less. For carbon and nitrogen removals in the system, the hydraulic detention time in the reactors and sludge appeared as the essential parameters in the process
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