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At least 19 recordsLinked to original sources
PubMed2002

Water treatment plants assessment at Talkha power plant.

Talkha power plant is the only power plant located in El-Mansoura. It generates electricity using two different methods by steam turbine and gas turbine. Both plants drew water from River Nile (208 m3 /h). The Nile raw water passes through different treatment processes to be suitable for drinking and operational uses. At Talkha power plant, there are two purification plants used for drinking water supply (100 m3/h) and for water demineralization supply (108 m3/h). This study aimed at studying the efficiency of the water purification plants. For drinking water purification plant, the annual River Nile water characterized by slightly alkaline pH (7.4-8), high annual mean values of turbidity (10.06 NTU), Standard Plate Count (SPC) (313.3 CFU/1 ml), total coliform (2717/100 ml), fecal coliform (0-2400/100 ml), and total algae (3 x 10(4) org/I). The dominant group of algae all over the study period was green algae. The blue green algae was abundant in Summer and Autumn seasons. The pH range, and the annual mean values of turbidity, TDS, total hardness, sulfates, chlorides, nitrates, nitrites, fluoride, and residual chlorine for purified water were in compliance with Egyptian drinking water standards. All the SPC recorded values with an annual mean value of 10.13 CFU/1 ml indicated that chlorine dose and contact time were not enough to kill the bacteria. However, they were in compliance with Egyptian decree (should not exceed 50 CFU/1 ml). Although the removal efficiency of the plant for total coliform and blue green algae was high (98.5% and 99.2%, respectively), the limits of the obtained results with an annual mean values of 40/100 ml and 15.6 org/l were not in compliance with the Egyptian decree (should be free from total coliform, fecal coliform and blue green algae). For water demineralization treatment plant, the raw water was characterized by slightly alkaline pH. The annual mean values of conductivity, turbidity, and TDS were 354.6 microS/cm, 10.84 NTU, and 214.6 mg/I, respectively. There was an increase in the results of conductivity, turbidity, total hardness, and TDS in carbon filter effluent which was attributed to the desorption of adsorbed ions on the carbon media. The removal efficiencies of turbidity, total hardness, and TDS indicated the high efficiency of the cationic filter. The annual removal efficiencies of conductivity, turbidity, chloride, and TDS proved the efficiency of the anionic filter for removing the dissolved and suspended ions. All of the recorded values of the pH, conductivity, turbidity, chlorides, hardness, and TDS of the mixed bed effluent indicated that the water at this stage was of high quality for boiler feed. The study recommended adjustment of coagulant and residual chlorine doses as well as contact time, and continuous monitoring and maintenance of the different units.

Egypt↗
PubMed1989

[Fly ash and its biological effects. 3. Exposure to dust of workers in the energy-generating industry (power plants and thermoelectric power stations)].

An evaluation of exposure to dust of workers employed at typical work-stands in power industry plants was made. Mean concentrations of respirable dust determined at 14 different work-posts range from 0.45 to 8.95 mg/m3, and of total dust from 1.55 to 85.0 mg/m3. Mean content of free crystalline silica in dust samples is less than 10%. At the work-stands where ash dust was encountered, the presence of respirable fibres at concentration below 0.2 fibre/cm3 was observed. In all ash samples alpha-quartz and mullite were found: in some of them also kaolinite and orthoclase were traced. Only at five out of all 14 work-stands examined mean concentration of respirable dust was lower than the hygienic standard value.

Air Pollutants, Occupational↗
PubMed2003

Micronucleus frequency is increased in peripheral blood lymphocytes of nuclear power plant workers.

Nuclear power plant workers are exposed to ionizing radiation at relatively low doses and for prolonged periods of time. To investigate the extent of genetic damage in these workers, a group of 133 nuclear power plant workers and 39 healthy controls were compared using the cytokinesis-block micronucleus assay. The frequency of micronuclei was significantly increased in peripheral lymphocytes of nuclear power plant workers (20.5 +/- 9.7% compared to 13.7 +/- 5.9%). A significant dose-response relationship was observed between micronucleus (MN) frequency and both the accumulated dose and the duration of employment (P < 0.01 for both variables after adjusting for age, gender and cigarette smoking) with an evident leveling off for exposures over 200 mSv. Accumulated dose and duration of employment were significantly correlated but exerted independent effects on MN frequency. For non-occupational parameters, age was significantly associated with the frequency of micronuclei, while gender was not. Smoking habit showed no overall effect, whereas increased chromosome damage was evident in smokers of more than 20 cigarettes per day. In conclusion, a dose-related association between MN frequency and exposure to ionizing radiation was evident in nuclear power plant workers, encouraging the application of the cytokinesis-block micronucleus assay in biomonitoring studies of human populations with prolonged exposure to ionizing radiation.

Adult↗
PubMed2003

A feasibility study on the predictive emission monitoring system applied to the Hsinta power plant of Taiwan Power Company.

The continuous emission monitoring system (CEMS) can monitor flue gas emissions continuously and instantaneously. However, it has the disadvantages of enormous cost, easily producing errors in sampling periods of bad weather, lagging response in variable ambient environments, and missing data in daily zero and span tests and maintenance. The concept of a predictive emission monitoring system (PEMS) is to use the operating parameters of combustion equipment through thermodynamic or statistical methods to construct a mathematic model that can predict emissions by a computer program. The goal of this study is to set up a PEMS in a gas-fired combined cycle power generation unit at the Hsinta station of Taiwan Power Co. The emissions to be monitored include nitrogen oxides (NOx) and oxygen (O2) in flue gas. The major variables of the predictive model were determined based on the combustion theory. The data of these variables then were analyzed to establish a regression model. From the regression results, the influences of these variables are discussed and the predicted values are compared with the CEMS data for accuracy. In addition, according to the cost information, the capital and operation and maintenance costs for a PEMS can be much lower than those for a CEMS.

Automation↗
PubMed2006

Radiation protection performance indicators at the Nuclear Power Plant Krsko.

Nuclear power plant safety performance indicators are developed "by nuclear operating organisations to monitor their own performance and progress, to set their own challenging goals for improvement, and to gain additional perspective on performance relative to that of other plants". In addition, performance indicators are widely used by regulatory authorities although the use is not harmonised. Two basic performance indicators related to good radiation protection practice are collective radiation exposure and volume of low-level radioactive waste. In 2000, Nuclear Power Plant Krsko, a Westinghouse pressurised water reactor with electrical output 700 MW, finished an extensive modernisation including the replacement of both steam generators. While the annual volume of low-level radioactive waste does not show a specific trend related to modernisation, the annual collective dose reached maximum, i.e. 2.60 man Sv, and dropped to 1.13 man Sv in 2001. During the replacement of the steam generators in 2000, the dose associated with this activity was 1.48 man Sv. The annual doses in 2002 and 2003 were 0.53 and 0.80 man Sv, respectively, nearing thus the goal set by the US Institute of Nuclear Power Operators, which is 0.65 man Sv. Therefore, inasmuch as collective dose as the radiation protection performance indicator are concerned, the modernisation of the Krsko nuclear power plant was a success.

Humans↗
PubMedDate not supplied

Prospective lung health monitoring in relation to a new power plant.

A new power plant has been in operation in Ashkelon since the end of 1990. In order to record the effect of the environmental changes on lung health, a prospective monitoring system was established during the planning and construction phase of the plant. Data about lung health in the general population as well as the sensitive population (asthma patients) are recorded, and air pollution is monitored by seven monitoring stations located within a 5-25 km radius of the power plant. The lung health monitoring system includes: (1) A record of all visits to the local emergency room. (2) A record of visits to ten representative outpatient clinics related to cardiac and pulmonary symptoms. (3) A close follow-up of 200 asthmatic children enrolled in the local pediatric pulmonary clinic. This includes spirometry four times yearly, an annual winter check-up by a pediatric pulmonologist, and daily symptoms diary filled in by each patient for two weeks after the spirometry. (4) Spirometry and health questionnaires filled out by the parents of the 3600 studied children once in three years. (5) Mortality rate monitoring, relying on the Ministry of Health death registration. This system has been in operation since 1988, collecting base line data; the follow-up is planned to be operating for ten years. A dynamic interaction of the environmental and epidemiological monitoring systems will facilitate more efficient control of the emmissions from the power plant and better protection of the health of the population.(ABSTRACT TRUNCATED AT 250 WORDS)

Child↗
PubMed1992

14C release from a Soviet-designed pressurized water reactor nuclear power plant.

The Paks Nuclear Power Plant in Hungary runs with four pressurized water reactors, each of 440-MWe capacity. Sampling systems have been developed and used to determine the 14C of various chemical forms (14CO2, 14CO, 14CnHm) in the airborne releases. The average normalized yearly discharge rates for the time period 1988-1991 are equal to 0.77 TBq GWe-1 y-1 for hydrocarbons and 0.05 TBq GWe-1 y-1 for CO2. The contribution of 14CO was less than 0.5% of the total emission. The 14C discharge rate is estimated to be four times higher than the corresponding mean data of Western European pressurized water reactors. The calculated effective dose equivalent to individuals living in the vicinity of the power plant, due to 14C release, was 0.64 microSv in 1991 while the effective dose equivalent due to the natural 14C level was 15 microSv y-1. The long-term global impact of the 14C release in the operational period of the plant (1982-1991) was 1,270 man-Sv. The 14C excess in the environmental air has been measured since 1989 by taking biweekly samples at a distance of 1.7 km from the nuclear power plant. The long-term average of radiocarbon excess coming from the power plant was 2 mBq m-3. The local 14C deposition was followed by tree ring analysis, too. No 14C increase higher than the uncertainty of the measurement (four per thousand = 0.17 mBq m-3) was observed.

Air Pollutants, Radioactive↗
PubMed2000

Environmental releases of radioactivity and the incidence of thyroid disease at the Ignalina Nuclear Power Plant.

The Ignalina Nuclear Power Plant consists of two Russian-made RBMK-1500 reactors. The plant uses Lake Druksiai as a natural reservoir for cooling water. Within the framework of the revised radiation dose limitation system, site-specific routine release conversion factors and maximum annual effective doses for the dominant radionuclides and pathways were evaluated for both atmospheric and aquatic releases. Using calculated release conversion factors, the locations of the highest predicted activity concentrations were determined for air and for the dilution zone of heated effluent water during the period 1984-1998. Committed effective doses for critical group members were less than 0.001 mSv for Ignalina Nuclear Power Plant airborne releases and less than 0.05 mSv for aquatic releases. These dose estimates are lower than the 1 mSv dose limit for the adjacent population. In the case of Ignalina Nuclear Power Plant, taking into account the uncertainties, a recommendation for the administrative dose constraint is 0.25 mSv y(-1). This dose level may scarcely affect human health. Interestingly, during screening for thyroid disorders, endocrinologists and pediatric-endocrinologists determined a dominance of abnormal thyroids (up to 60%) among school children in the vicinity of Ignalina NPP. The data on neonatal screening for congenital hypothyroidism and transient hyperthyrotropinemia, however, suggested a possibility that the majority of abnormal thyroid cases were related to stable iodine deficiency. Thus, the influence of Ignalina Nuclear Power Plant on thyroid disorders is highly conjectural and unlikely to be associated with the observed levels of childhood thyroid disease.

Adult↗
PubMed2002

Concentration of caesium-137, cobalt-60 and potassium-40 in some wild and edible plants around the nuclear power plant in Bulgaria.

The activities of 137Cs, 60Co and 40K were determined in samples of wild (Taraxacum officinale, Plantago lanceolata and Populus nigra 'Italica') and edible (vegetable, corn, fruit) plants as well as soil collected from the 30 km safety zone of the Bulgarian NPP "Kozloduy" and comparisons with earlier measurements and analyses of samples from other regions and with literature values were performed. The derived transfer factors for 137Cs and 40K from soil to plants ranged between 0.002 and 0.009 for 137Cs, and between 0.09 and 0.35 for 40K. The individual effective dose (calculated from the present results and data on the activity of other foodstuffs and from information about dietary habits) comprises 4.5% of the annual dose limit.

Bulgaria↗
PubMed2005

Influence of operating conditions on the ammonia electro-oxidation rate in wastewaters from power plants (ELONITA technique).

Power plants, like many other industries, are confronted with the need to reduce the nitrogen content of their wastewaters. Indirect electro-oxidation, through hypochlorite formation, is a possible answer to an ammonia-nitrogen problem, through converting it into gaseous nitrogen. Several parameters affect the ammonia oxidation rate: current density, chloride concentration and the presence of oxygen-containing anions, mainly SO(4)(2-), CO(3)(2-) and PO(4)(3-). pH values between 5.5 and 10 have been found to have no effect on the ammonia oxidation rate. However, at higher pH values (above 11), the oxidation slows down and chlorate ions appear. A model can be fitted from the experiments to predict the ammonia oxidation rate based on four main parameters: pH, current density, sulfate concentration and chloride concentration. The average difference between the predicted oxidation rates and the experimental measures is only 6.5%. This model confirms that the optimal operating conditions are a high chloride concentration (7 gl(-1)), no sulfate and a high current density (1200 Am(-2)).

Ammonia↗
PubMed2005

Air quality impact of the coal-fired power plants in the northern passageway of the China West-East Power Transmission Project.

This paper analyzes the air quality impacts of coal-fired power plants in the northern passageway of the West-East Power Transmission Project in China. A three-layer Lagrangian model called ATMOS, was used to simulate the spatial distribution of incremental sulfur dioxide (SO2) and coarse particulate matter (PM10) concentrations under different emission control scenarios. In the year 2005, the emissions from planned power plants mainly affected the air quality of Shanxi, Shaanxi, the common boundary of Inner Mongolia and Shanxi, and the area around the boundary between Inner Mongolia and Ningxia. In these areas, the annually averaged incremental SO2 and PM10 concentrations exceed 2 and 2.5 microg/m3, respectively. The maximum increases of the annually averaged SO2 and PM10 concentrations are 8.3 and 7.2 microg/m3, respectively, which occur around Hancheng city, near the boundary of the Shaanxi and Shanxi provinces. After integrated control measures are considered, the maximum increases of annually averaged SO2 and PM10 concentrations fall to 4.9 and 4 microg/m3, respectively. In the year 2010, the areas affected by planned power plants are mainly North Shaanxi, North Ningxia, and Northwest Shanxi. The maximum increases of the annually averaged SO2 and PM10, concentrations are, respectively, 6.3 and 5.6 microg/m3, occurring in Northwest Shanxi, which decline to 4.4 and 4.1 microg/m3 after the control measures are implemented. The results showed that the proposed power plants mainly affect the air quality of the region where the power plants are built, with little impact on East China where the electricity will be used. The influences of planned power plants on air quality will be decreased greatly by implementing integrated control measures.

Air Pollutants↗
PubMed1988

Concentrations of Co, Cd, Cr, Ni, and Zn in crop plants cultivated in the vicinity of coal-fired power plants.

In order to determine the effect of airborne emissions of trace elements (Co, Cd, Cr, Ni and Zn) from coal-fired power plants on the environment, concentrations were determined in different species of agricultural plants from the local environment (1-15 km radius) and compared with the corresponding concentrations in soils and fallout. The spatial distribution of trace elements in the soil over 7 years did not indicate any significant increased exposure to plants. In agricultural soils exposed to particle fallout produced by the combustion of brown coal, the trace element content changes slowly; it may decrease owing to its removal with the harvesting of crop plants and due to an insufficient supply of fertilizers. Particle fallout from local power plants is too small to change significantly the natural distribution pattern of trace elements in soils and in plant tissues. For monitoring purposes attention should be paid to the leaves and roots of sugar beet and oat seeds in the vicinity of coal-fired power plants.

Cadmium↗
PubMed2004

Radiological characteristics and investigation of the radioactive equilibrium in the ashes produced in lignite-fired power plants.

Coal- and lignite-fired power plants produce significant amounts of ashes, which are quite often being used as additives in cement and other building materials. In many cases, coal and lignite present high concentrations of naturally occurring radionuclides, such as 238U, 226Ra, 210Pb, 232Th and 40K. During the combustion process, the produced ashes are enriched in the above radionuclides. The different enrichment of the various radionuclides within a radioactive series, such as that of 238U, results in the disturbance of radioactive secular equilibrium. An extensive research project for the determination of the natural radioactivity of lignite and ashes from Greek lignite-fired power plants is in progress in the Nuclear Engineering Department of the National Technical University of Athens (NED-NTUA) since 1983. This paper presents detailed results for the natural radioactivity, the secular radioactive equilibrium disturbance and the radon exhalation rate of the fly-ash collected at the different stages along the emission control system of a lignite-fired power plant as well as of the bottom-ash. From the results obtained so far, it may be concluded that 226Ra radioactivity of fly-ash in some cases exceeds 1 kBq kg(-1), which is much higher than the mean 226Ra radioactivity of surface soils in Greece (25 Bq kg(-1)). Furthermore, the radioactivity of 210Pb in fly-ash may reach 4 kBq kg(-1). These results are interpreted in relation to the physical properties of the investigated nuclides, the temperature in the flue-gas pathway, as well as the fly-ash grain size distribution. It is concluded that towards the coldest parts of the emission control system of the power plant, the radioactivity of some natural nuclides is gradually enhanced, secular radioactive equilibrium is significantly disturbed and the radon exhalation rate tends to increase.

Air Pollutants, Radioactive↗
PubMed1977

Mercury emissions from geothermal power plants.

Geothermal steam used for power production contains significant quantities of volatile mercury. Much of this mercury escapes to the atmosphere as elemental mercury vapor in cooling tower exhausts. Mercury emissions from geothermal power plants, on a per megawatt (electric) basis, are comparable to releases from coal-fired power plants.

Air Pollutants↗
PubMed1987

[Occupational radiation exposures during maintenance activities at nuclear power plants].

Occupational exposures at nuclear power plants occur mostly during maintenance activities rather than during routine reactor operation. In this paper, statistical summaries of occupational exposures during routine maintenance activities for the years 1982-84 at nuclear power plants in Japan are presented, including comparison of the exposure levels by reactor type and by plant age. Average annual collective doses per reactor for BWRs and PWRs are 7.30 man-Sv and 2.84 man-Sv, respectively, and 78% and 89% of annual doses are incurred during maintenance activities. Average annual outage days of BWRs and PWRs for routine maintenance are 102 d and 97 d. Annual collective doses per reactor, most of which occur during maintenance activities, usually increase with plant age. Higher collective doses are observed for routine maintenance performed on older reactors as compared to newer reactors, especially in BWRs. Collective doses accrued during respective routine maintenance activities have a significant correlation with duration of maintenance and number of workers involved in maintenance.

Environmental Exposure↗
PubMedDate not supplied

[Molecular-biological nature of morphological abnormalities induced by chronic irradiation in coniferous plants from the Chernobyl nuclear power plant exclusion zone: emphasis on a possible role of the cytoskeleton].

Results of the analysis of morphological abnormalities in coniferous plants from the Chernobyl exclusion zone are described. It is shown that such features as total and individual protein content, genome organization and peculiarities of its expression, and karyotype are different for the control and morphologically abnormal needles. A possible role of the cytoskeleton structures in the abnormal morphogenesis in plants is discussed.

Cytoskeleton↗
PubMed1983

Role of inhalation studies with animals in defining human health risks for vehicle and power plant emissions.

Automotive vehicles and power plants using fossil fuels emit a complex array of gases and particulate material. The physical and chemical characteristics of these emissions vary markedly between sources and comprise only a portion of the contributors to air pollution exposure of people. Further, it is well recognized that a single form of self-inflicted air pollution, cigarette smoking, is the dominant cause of air pollution-induced disease. These factors minimize our potential for developing an adequate understanding of the health effects of vehicle and power plant emissions by studying only people. The alternative is to use the human data to the extent feasible and complement it with information gained in studies with macromolecules, organelles, cells, tissues and whole animals. Within this context, this paper reviews the use of inhalation studies with animals for defining human health risks of airborne materials, especially particulate materials. The major areas covered are: the fate of inhaled materials, the pathogenesis of disease induced by inhaled materials and long-term animal studies to identify late-occurring effects. Emphasis is placed on the utility of studies in whole animals as integrative models in which the multiple processes such as xenobiotic metabolism, cell injury, repair, transformation and promotion under the influence of many host factors interact in a manner that may not be directly observed in isolated cells or tissues.

Air Pollutants↗