Papers by Keyword: Total Phosphorus

Abstract: This paper describes the fabrication, characterization and the application of the photocatalytic TiO₂ nanofiber as the photocatalyst for the digestion of total phosphorus (TP). The nanoTiO₂ fibers were fabricated by the electro-spinning technique on silicon substrate. Under the conditions of room temperature (25 degrees Celsius) and humidity less than 40%, the TiO₂ fabricated by the electro-spinning presents a silky coagulation appearance, which can be converted to the nanofiber appearance by annealed in the muffle furnace at 450 degrees Celsius for 10 hours. X-ray diffraction (XRD) examination shows that the silky coagulation can be converted to anatase-type TiO₂. The absorbance values of different phosphate concentrations after exposure in UV light at the intensity of 7000μW/cm² were tested in this paper. Sodium tripolyphosphate solutions serve as the water sample of TP, and five standard concentrations (by weight of P) are 0.0mg/L, 1.0mg/L, 2.0mg/L,3.0mg/L and 4.0mg/L, respectively. The digestion rate exhibits satisfied linearity ranges from 0.0mg/L to 4.0mg/L with acceptable linearity R² of calibration curve, in both digestion temperature of 25 degrees Celsius and 50 degrees Celsius.

Abstract: This study, through on-site sampling, performs a content analysis of total organic carbon (TOC), total nitrogen (TN) and total phosphorus (TP) contained in Kaohsiung Harbor surface sediments, and accordingly evaluates their temporal-spatial distribution and sources. The results indicate that the TOC content of Kaohsiung Harbor sediments ranges from 1.0 to 7.0% (average 2.3±0.3%) with the highest level of 6.8±0.2% in the Salt River estuary. The TN content ranges from 990 to 10,582 mg/kg (average 2,665±1,800 mg/kg) and the TP values are between 178 and 784 mg/kg (average 363±147 mg/kg). The content distribution of TOC, TN and TP demonstrates a high-to-low sequence: estuary, channel and Harbor, indicating that the organics in the sediments are mainly from the upstream inflow of rivers. The TOC, TN and TP contents in the wet season are obviously higher than those in the dry season, which might result from the terrestrial organics flushed into the Harbor by the seasonal abundant and concentrated precipitation. The C/N ratio of Kaohsiung Harbor sediments is between 4.6 and 26.9, with an average value of 11.9±6.6. Through further estimation, 76.5% of the TOC is identified as terrestrial, and the TN is dominated by marine autogenetic sources.

Abstract: The total phosphorus in water mainly exists in the forms of phosphate, condensed phosphate, and the compound of organophosphorus. Chemical sampling analysis method has low measuring accuracy and takes long time. NIPGA technology is used in order to detect the total phosphorus content in sewage quickly, and MCNP-4C is used to take simulating calculation. The calculating results show that the measuring accuracy is lower when the total phosphorus content is less than 0.10 mg/L. But this approach can meet the measurement requirements of total phosphorus content in II-type, III-type, IV-type and V-type water.

Abstract: This paper studied the relationship of chlorophyll-a, total nitrogen (TN) and total phosphorus (TP) concentration based on the conventional monitoring data in 2013. The results showed that the concentration of chlorophyll-a (Chl.a) had obvious correlation with TN, TP in July and August, and there was no relationship in October. Furthermore, content of nitrogen is more relevant to chlorophyll-a than phosphorus by regression analysis. Therefore, it was indicated that nitrogen and phosphorus nutrients had intimated relationships with algae growth.

Abstract: In this study, water samples were collected from water system of Beijing urban area and analyzed by inductively coupled plasma-atomic emission spectrometry (ICP-AES) method and total organic carbon analyzer to determine the contents of TOC, TP and TN. The results revealed that among the 133 samples there were respectively 16.54%, 28.57% and 39.85% samples’ detected TOC, TP and TN higher than the permitted values. It was especially serious about the sewage outlet along the riverside.

Abstract: The water environment is a system with many uncertainties and requires doing research by the method of uncertainty. Based on the dynamics of river hydrology and water quality, the uncertainty and incompleteness characteristics of monitoring information and frequency, each parameter in the model of Dillion is managed by using the theory of Unascertained Mathematics and unascertained expected value. This paper probes into the study of the permissible input of total phosphorus of Poyang Lake in Jiangxi and the credible level calculation. With this method, not only can the unascertained expected value of the permissible input of total phosphorus be calculated, its subjective reliability can also be obtained on the basis of the rules of four fundamental operations of unascertained.

Abstract: Water samples were collected from the upstream to the downstream of a seasonal river, the Taizi River, and its main tributaries in dry season, normal season, and wet season. The variations of NH₃-N, and total phosphorus (TP) within a hydrological year were analyzed, aimed to study the pollution characteristics and sources of the water bodies. It was found that the tributaries of the Taizi River were heavily contaminated by NH₃-N, with 83.8%, 100% and 100% of the sampling sites exceeding the fifth level in the dry season, wet season and normal season, respectively. The concentration of TP in the dry season fluctuated wildly, which was much higher than those in the wet and normal season. Compared with the permissible levels set by the environmental quality standards for surface water standard (GB3838-2002) of China, 57.1% of the sampling sites in the main stream and tributaries of the Taizi River belong to the fifth level or exceed the fifth level in the dry season, and only 7.1% of the sampling sites were belonging to the fifth level or exceed the fifth level in the wet and normal season. Overall, the waterbody of Taizi River was more seriously polluted by urban domestic sewage and point source of industrial wastewater.

Abstract: Two aquatic macrophytes (Lythrum salicaria and Alisma plantago-aquatica) were grown in monoculture to test the relative growth rate (RGR) and abilities of removing total phosphorus (TP) by the manipulative indoor experiment. A nutrient treatment consisted of two levels of phosphorus [ low (3 mg L^-1 N) and high (12 mg L^-1 N) ] of nutrient solution. Result revealed that nutrients had significant affect on the RGR, however the RGR of the species was non-significant. The results showed that TP in wastewater were significantly higher from unvegetated microcosms compared to vegetated. L. salicaria was shown to be best removal effect with the removal rates of 81.7% and 91.1% at low and high concentrations of TP.

Abstract: Total phosphorus is an much important key water quality parameter . In view of the technical defects of existing detection methods and instruments for in situ monitoring total phosphorus, a new detection method based on ultrasonic assisted sample digestion and spectrum analysis was put forward in this paper, and the automatic monitoring system prototype based on such detection method had been developed. Aiming at wastewater treatment, the spot experiment had been carried out to contrast prototype with Chinas national standard analysis method for on line measuring total phosphorus in the water, and the results of the comparative experiment showed that the automatic monitoring instrument prototypes had good repeatability (10%) and high accuracy (±10%), which met the technical qualifications of Chinas environmental protection industry standards.

Abstract: This research has examined the aquatic plants ability of removing N and P with the experiment materials of the aquatic plants in the river system in Chaohu Region. Results revealed that Ludwigia peploides subsp, Vallisneria spiralis, Water Hyacinth and Cyperus papyrus contribute to removing TN in water to the effect which correlates the growth rate of the plants. 1) Particularly, Water Hyacinth, which grows the fastest among the sample plants, effects with the highest efficiency in removing TN, with the removal ratio of about 77%, 6.8 times that of the control group; 2) 4 aquatic plants function with higher efficiency in removing NH3-N than TN, and the plants in Test 8d remove NH3-N up to the removing ratio of 65-92% or so; 3) 4 aquatic plants tend to degrade NO₃^--N at the ratio similar to TN, and the absorptive effect of Water Hyacinth tops among the 4 plants, while under the same conditions, the papyrus remains the lowest with the absorptive ratio of only 31.7%; 4) and the regulation that the experiment plants remove the TP in water differs from TP degradation, for, in the early stage of the experiment, plants in Test 20d remove phosphorus at the high rate; however, in the later stage of the experiment, the concentration of phosphorus in water remains stable. At the end of the experiment, the phosphorus removal ratio reached 47.2%, while the ratio that the papyrus removed the phosphorus was only 21.5%. These data suggest that the aquatic plants in Chaohu Region can exert efficient remediation effect upon the eutrophic water.