Chemical Neutralization to Control Denting in Nuclear Steam Generators

1983 ◽  
Vol 105 (4) ◽  
pp. 763-770 ◽  
Author(s):  
T. A. Beineke ◽  
J. F. Hall ◽  
K. E. Marugg ◽  
D. B. Scott ◽  
R. M. Orsulak ◽  
...  
Keyword(s):  
Boric Acid ◽  
Calcium Hydroxide ◽  
Calcium Concentration ◽  
Chloride Concentration ◽  
Line Treatment ◽  
Steam Generators ◽  
Adverse Side Effects ◽  
On Line ◽  
Full Power ◽  
Power Operation

Laboratory testing at Combustion Engineering has indicated promise in controlling simulated steam generator tube denting through chemical neutralization. Testing was limited to on-line treatment, and two neutralizers have been evaluated: (i) calcium hydroxide, and (ii) boric acid. On-line treatment with calcium hydroxide successfully halted active denting whenever the bulk calcium concentration (in ppm) equaled or exceeded the bulk chloride concentration (in ppm). Calcium hydroxide also was effective as an alternative to ammonia as a pH controlling agent in two tests conducted without ingress of chloride. On-line treatment with boric acid consisted of a four-day soak at simulated low (approximately 30 percent) power with 50 ppm B followed by one month full-power operation with 10 ppm B. This treatment also halted denting. Nondestructive and destructive examination of test boilers gave no indication of adverse side effects associated with either neutralizer.

Experimental Investigation on Denting in PWR Steam Generators: Causes and Corrective Actions

1983 ◽  
Vol 105 (4) ◽  
pp. 755-762 ◽  
Author(s):  
F. Nordmann ◽  
G. Pinard-Legry ◽  
J. Daret ◽  
J. P. Brunet
Keyword(s):  
Carbon Steel ◽  
Boric Acid ◽  
Calcium Hydroxide ◽  
River Water ◽  
Ph Value ◽  
Steam Generators ◽  
Oxide Morphology ◽  
Specific Effects ◽  
On Line ◽  
Oxygen Addition

Denting studies have been undertaken in order to assess the influence of the most important parameters which could initiate corrosion of the carbon steel occurring in the tube-tube support plate crevices of some PWR steam generators. Tests have been carried out in model boilers where feedwater was polluted with sea or river water. Specific effects of chloride or sulfate and influence of oxygen content, magnetite addition and pH value were investigated. In magnetite prepacked crevices, denting is obtained within 1000 hrs for seawater pollution of 0.3 ppm chloride at the blowdown. In neutral chloride or in river water, denting is observed only with oxygen addition. Denting prevention is effective in the case of an on-line addition of phosphate, boric acid, or calcium hydroxide. For denting stopping, boric acid or calcium hydroxide is efficient even with a high seawater pollution. Soaks cannot stop denting if they are not followed by an on-line treatment (boric acid, calcium hydroxide). With quadrifoil holes, denting doesn’t occur. In very severe test conditions, 13 percent Cr steel can be corroded, but the corrosion rate is low and oxide morphology is different from that growing on carbon steel.

scholarly journals Optical Methods for On-line Quality Assurance of Welding Processes in Nuclear Steam Generators

10.5772/15579 ◽  
2011 ◽  
Author(s):  
Adolfo Cobo ◽  
Jesus Ma ◽  
David Solana ◽  
Alfonso Alvarez-de-Miranda ◽  
Pilar-Beatriz Garcia-Allende ◽  
...  
Keyword(s):  
Quality Assurance ◽  
Optical Methods ◽  
Steam Generators ◽  
On Line ◽  
Welding Processes

scholarly journals Nickel Effect on Pomegranate Cracking, Nutrient Concentrations, and Biochemical Parameters of Pomegranate Peel

HortScience ◽  
2018 ◽  
Vol 53 (11) ◽  
pp. 1677-1682
Author(s):  
Olga Dichala ◽  
Ioannis Therios ◽  
Magdalene Koukourikou-Petridou ◽  
Aristotelis Papadopoulos
Keyword(s):  
Field Experiment ◽  
Boric Acid ◽  
Biochemical Parameters ◽  
Calcium Concentration ◽  
Punica Granatum ◽  
Nutrient Concentrations ◽  
Crop Loss ◽  
Fruit Maturation ◽  
Fruit Peel ◽  
Pomegranate Peel

A field experiment was conducted in a pomegranate (Punica granatum L.) orchard of the well-known cultivars Wonderful and Acco, located in the farm of Aristotle University. The trees were sprayed, every 15 days from flowering (April) to fruit maturation (September), with solutions containing 0, 25, 50, 100 μm Ni, and 100 μm Ni + 100 μm B prepared with Ni(NO3)2·6H2O and boric acid. Leaves and fully ripe fruits were initially sorted into cracked and uncracked ones, then further separated into peel and seeds, sampled, and analyzed. Nickel sprays were effective in controlling fruit splitting as well as Ca and Mg concentration of fruit peels. The correlation between cracking level and Ni concentration in solution was linear and negative. Cracking percentage with 50 μm Ni was lower in ‘Wonderful’, whereas no difference was recorded between the cultivars in the remaining treatments. Leaves had the smallest Ni concentration compared with fruit peel and seeds. Calcium concentration of pomegranate peels was higher than that of control peel at 50 μm Ni in ‘Wonderful’. Concerning ‘Acco’, the treatments 25 μm Ni, 50 μm Ni, and 100 μm Ni + 100 μm B reduced Ca concentration, compared with control. ‘Wonderful’ fruit peel contained more phenolics than ‘Acco’. The treatments 25, 50, and 100 μm Ni increased significantly the flavonoid concentration of fruit peels. The antioxidant capacity ferric-reducing antioxidant potential (FRAP) was linearly increased with Ni concentration in solution in ‘Wonderful’, whereas in ‘Acco’ it decreased at 25 and 50 μm Ni. Our data indicates that improving Ni nutrition of pomegranate can potentially reduce crop loss due to cracking and modified phenol and flavonoid concentration and FRAP value of fruit peel.

scholarly journals FULL POWER OPERATION OF THE LAMPF 805 MHz SYSTEM.

1970 ◽  
Author(s):  
R Jameson ◽  
J Wallace ◽  
R Cady ◽  
D Liska ◽  
J Sharp ◽  
...  
Keyword(s):  
Full Power ◽  
Power Operation

Cyclic Operation of Supercritical High Pressure Feedwater Heater Study

2013 ◽  
Author(s):  
Kellen Muldoon
Keyword(s):  
High Pressure ◽  
Renewable Energy Sources ◽  
Primary Component ◽  
Temperature Data ◽  
Actual Performance ◽  
Cyclic Operation ◽  
On Line ◽  
Full Power ◽  
Flexible Load ◽  
Recent Project

As more renewable energy sources come on line with the inherent inconsistency of load dispatch feedwater heaters become subject to more frequent and rapid cyclic operation. In a recent project, American Exchanger Services (AM-EX) was asked to gather and analyze operating information on a high pressure feedwater heater during daily rapid load changes. This particular supercritical coal plant was designed to operate in flexible load environments, thus acquiring data during the summer months was optimal. The heater was run from rest to full power while temperature data was acquired. All data from the study and supporting plant information was used to generate models for preparing maintenance projections, informing future designs, and repair recommendations. The primary component of focus is the desuperheating zone exhaust where tube failure tends to be greatest caused by wet wall conditions. The result of the analysis was less conclusive than was anticipated. Actual performance of the heaters is a key issue and there were specific indications that the heaters were not performing to specifications. A more detailed thermal performance analysis using the ASME PTC12.1 should be considered to accurately determine the extent to which the heaters are meeting design performance.

Binding of calcium by human plasma proteins under simulated physiologic conditions

1964 ◽  
Vol 19 (2) ◽  
pp. 292-296 ◽  
Author(s):  
Irene R. Held ◽  
Smith Freeman
Keyword(s):  
Human Plasma ◽  
Plasma Proteins ◽  
Protein Concentration ◽  
Calcium Concentration ◽  
Gamma Globulin ◽  
Chloride Concentration ◽  
Total Calcium ◽  
Total Protein Concentration ◽  
Plasma Albumin

The binding of calcium to human plasma albumin, alpha, beta, and gamma globulins was studied with the aid of an ultracentrifuge. The amount of calcium bound to these separated proteins was determined in solutions with electrolyte concentrations and pH within physiological ranges. The total calcium concentration was 2.35–2.90 mm/liter H2O and the total protein concentration was 3.91–4.29 g/100 ml H2O. In these solutions no significant differences were found for the binding of calcium (expressed as mm Ca++ bound per gram protein) by albumin, alpha, and beta globulins; the average values obtained were, respectively, 0.016, 0.018, and 0.023. Significantly less calcium was bound by gamma globulin; 0.009 mm/gram. The pH was varied between 7.200–7.550 and the sodium chloride concentration between 114–157 mEq Na per liter. These changes did not measurably affect the amount of calcium bound to albumin. protein-bound calcium; ultracentrifugation and determination of protein-bound calcium; plasma globulin-bound calcium; plasma albumin-bound calcium Submitted on July 2, 1963

Automated Fluorometric Analysis of Calcium Pantothenate in Multivitamin Preparations

1978 ◽  
Vol 61 (3) ◽  
pp. 720-726
Author(s):  
Ram B Roy ◽  
Anthony Buccafuri
Keyword(s):  
Acid Solution ◽  
Boric Acid ◽  
Fluorescence Intensity ◽  
Analytical Data ◽  
Boric Acid Solution ◽  
Calcium Pantothenate ◽  
Magnesium Trisilicate ◽  
On Line ◽  
The Mean ◽  
Fluorometric Analysis

Abstract An automated fluorometric procedure is described for assaying calcium pantothenate in multivitamin preparations. Sample extracts containing calcium pantothenate are treated on-line with a slurry of magnesium trisilicate which removes any interfering riboflavin that may be present. The nitrate is resampled, mixed online with a slurry of Dowex 50W-X4 (H+) which removes any interfering β-alanine that may be present, and dialyzed. Dialysates are hydrolyzed in an alkaline medium and reacted with a mixture of o-phthalaldehyde and 2-mercaptoethanoI in boric acid solution. The fluorescence intensity due to the formation of a fluorogenic compound is measured at 455 nm after excitation at 350 nm. The procedure developed is capable of analyzing 20 samples/hr. Analytical data indicate that calcium pantothenate is assayed reliably both from real and synthetic multivitamin preparations. The mean recovery of calcium pantothenate added to sample solutions of tablet composites was 95.4%.

Radiation shielding requirements for the full power operation of the linear IFMIF prototype accelerator (LIPAc) at Rokkasho

2019 ◽  
Vol 146 ◽  
pp. 293-298 ◽  
Author(s):  
Keitaro Kondo ◽  
Beatriz Brañas ◽  
Philippe Cara ◽  
Hervé Dzitko ◽  
Dominique Gex ◽  
...  
Keyword(s):  
Radiation Shielding ◽  
Full Power ◽  
Power Operation
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