scholarly journals ENTUPIMENTO DE GOTEJADORES CONVENCIONAIS POR PRECIPITADOS QUÍMICOS DE CARBONATO DE CÁLCIO E MAGNÉSIO, COM QUATRO ÍNDICES DE SATURAÇÃO DE LANGELIER

Irriga ◽  
2008 ◽  
Vol 13 (4) ◽  
pp. 525-539 ◽  
Author(s):  
Ralini Ferreira de Mélo ◽  
Rubens Duarte Coelho ◽  
Marconi Batista Teixeira
Keyword(s):  
Water Distribution ◽  
Saturation Index ◽  
Operating Time ◽  
Test Conditions ◽  
Terra Preta ◽  
Langelier Saturation Index ◽  
Distribution Uniformity ◽  
Calcium And Magnesium ◽  
Saturation Indexes ◽  
Bench Testing

ENTUPIMENTO DE GOTEJADORES CONVENCIONAIS POR PRECIPITADOS QUÍMICOS DE CARBONATO DE CÁLCIO E MAGNÉSIO, COM QUATRO ÍNDICES DE SATURAÇÃO DE LANGELIER  Ralini Ferreira de Mélo1; Rubens Duarte Coelho2; Marconi Batista Teixeira21Escola Agrotécnica Federal de Vitória de Santo Antão, Propriedade Terra Preta, Vitória de Santo Antão, PE, [email protected] de Engenharia Rural, Escola Superior de Agricultura Luiz de Queiroz, Universidade de São Paulo, Piracicaba, SP  1 RESUMO Com o objetivo de avaliar a influência da indução forçada de precipitados químicos à base de carbonatos de cálcio e magnésio no coeficiente de variação e uniformidade de distribuição de água, foi realizado um ensaio no Laboratório de Irrigação da ESALQ/USP, utilizando-se quatro índices de saturação de Langelier (ISL): ISL -2,268; ISL 0,469; ISL 1,156 e ISL 1,439. Em cada ensaio com um determinado ISL, foram utilizados oito tipos de gotejadores convencionais, instalados em uma bancada com11 mde comprimento. As obstruções observadas nos gotejadores, tanto parciais como totais decorrentes do tempo de funcionamento, resultaram em aumento do coeficiente de variação e redução drástica da uniformidade de distribuição de água. Para as condições de ensaio realizado, observou-se que o índice de saturação de Langelier não deve ser usado como único parâmetro para prever a obstrução dos gotejadores. UNITERMOS: irrigação localizada, cálcio e magnésio, Índice de Saturação de Langelier.  MÉLO, R. F.  de; COELHO, R. D.; TEIXEIRA, M. B. CLOGGING OF A COMMERCIAL DRIPPERS BY CALCIUM AND MAGNESIUM PRECIPITATES USING FOUR LANGELIER SATURARION INDEXES  2 ABSTRACT An essay was carried out in the laboratory of irrigation at ESALQ/USP   to evaluate the effect of calcium and magnesium precipitates on the variation and uniformity coefficients in irrigation drippers. Four Langelier saturation indexes (LSI) (-2,268; 0,469; 1,156; 1,439) and eight commercial drippers were used. They were installed on an 11m bench testing apparatus. Both partial and total obstructions of the drippers were observed over the operating time increasing the variation coefficient and reducing the water distribution uniformity. Within the test conditions, LSI should not be used as a single parameter to estimate dripper clogging. KEY WORDS: drip irrigation, calcium and magnesium, Langelier saturation index

scholarly journals Scaling and Corrosion Potential in Drinking Water Distribution Systems of Meshginshahr City, Iran Using Langelier Saturation Index and Ryznar Stability Index

2020 ◽  
Vol 9 (3) ◽  
pp. 201-208
Author(s):  
Kamal Hasani ◽  
◽  
Hadi Sadeghi ◽  
Abdollah Dargahi ◽  
Mehdi Vosoughi ◽  
...  
Keyword(s):  
Drinking Water ◽  
Distribution System ◽  
Water Distribution ◽  
Water Distribution System ◽  
Saturation Index ◽  
Stability Index ◽  
Drinking Water Distribution System ◽  
Scaling Potential ◽  
Drinking Water Distribution ◽  
Langelier Saturation Index

Background: Corrosion and scaling are major problems in the drinking water facilities causing problems such as water loss, recued life of facilities, pipe punctures, clogging of pipes, and pressure loss in drinking water distribution system. This study aims to determine the corrosion and scaling potential in drinking water distribution system of Meshginshahr, Ardebil, Iran. Methods: This descriptive cross-sectional study was conducted during the two seasons (summer and winter) in 2019. A total of 20 water samples, which were obtained by averaging 100 samples, were analyzed to determine the corrosion and scaling potential using Langelier Saturation Index and Ryznar Stability Index. Results: The results showed that the annual average of LSI and RSI were -1.34 and 10.03, respectively, indicating that the drinking water of Meshginshahr was corrosive and scale-forming. Conclusion: Therefore, it is necessary to constantly evaluate the drinking water supply resources of this city and try to adjust the pH of water and control other factors affecting corrosion, including concentrations of chloride, dissolved oxygen, and sulfate.

The influence of aeration on the change in corrosiveness and aggressiveness of groundwater

2015 ◽  
Vol 16 (2) ◽  
pp. 445-452 ◽  
Author(s):  
Tadeusz Siwiec ◽  
Magdalena M. Michel ◽  
Lidia Reczek ◽  
Piotr Nowak
Keyword(s):  
Carbon Dioxide ◽  
Water Treatment ◽  
Saturation Index ◽  
Stability Index ◽  
Water Layer ◽  
Water Stability ◽  
Air Bubbles ◽  
High Concentration ◽  
Aeration Time ◽  
Langelier Saturation Index

A high concentration of aggressive carbon dioxide disturbs many technological processes in water treatment. It also causes the development of corrosion in steel and concrete. De-acidification of groundwater by means of air bubbles alters pH and the concentration of aggressive carbon dioxide. This was investigated for the variables of air flow (Q = 20–50 L h−1) and height of water layer (H = 25–75 cm) as well as aeration time (t = 0–20 min). The obtained three-parameter models showed good correlation with the experimental results, except in a few cases where r2 was bigger than 0.9. Furthermore, they allow for prediction of an increase of pH and a decrease in concentration of aggressive carbon dioxide in aerated water. The effectiveness of de-acidification of groundwater was evaluated using indices of water stability (Langelier Saturation Index, Precipitation Index, Ryznar Stability Index, Aggressiveness Index and Index of Aggressiveness). Although as a result of aeration an increase of pH over 7 was observed, the non-corrosive values of the indices were not reached. This was due to a very low alkalinity of water, which was 0.7 meq L−1.

scholarly journals Effect of Pulse Drip Irrigation Duration on Water Distribution Uniformity

Water ◽  
2020 ◽  
Vol 12 (8) ◽  
pp. 2276
Author(s):  
David Lozano ◽  
Natividad Ruiz ◽  
Rafael Baeza ◽  
Juana I. Contreras ◽  
Pedro Gavilán
Keyword(s):  
Drip Irrigation ◽  
Water Distribution ◽  
Crop Yields ◽  
Irrigation System ◽  
Irrigation Schedule ◽  
Sandy Soils ◽  
Field Evaluation ◽  
Irrigation Performance ◽  
Standard Procedures ◽  
Distribution Uniformity

Developing an appropriate irrigation schedule is essential in order to save water while at the same time maintaining high crop yields. The standard procedures of the field evaluation of distribution uniformity do not take into account the effects of the filling and emptying phases of the irrigation system. We hypothesized that, in sloping sandy soils, when short drip irrigation pulses are applied it is important to take into account the total water applied from the beginning of irrigation until the emptying of the irrigation system. To compute distribution uniformity, we sought to characterize the filling, stable pressure, and emptying phases of a standard strawberry irrigation system. We found that the shorter the time of the irrigation pulse, the worse the distribution uniformity and the potential application efficiency or zero deficit are. This effect occurs because as the volume of water applied during filling and emptying phases increases, the values of the irrigation performance indicators decrease. Including filling and emptying phases as causes of non-uniformity has practical implications for the management of drip irrigation systems in sloping sandy soils.

scholarly journals Influence of the degree of soil organic matter lability on the calcium carbonate equilibrium of soil water

2010 ◽  
Vol 5 (No. 2) ◽  
pp. 58-68
Author(s):  
S. Kužel ◽  
L. Kolář ◽  
J. Gergel ◽  
J. Peterka ◽  
J. Borová-Batt
Keyword(s):  
Organic Matter ◽  
Calcium Carbonate ◽  
Soil Water ◽  
Saturation Index ◽  
Farmyard Manure ◽  
Hot Water ◽  
Organic Matters ◽  
Langelier Saturation Index ◽  
The Stability ◽  
Carbonate Equilibrium

: In average samples of three sandy-loamy acid Cambisols from a South Bohemian area labile organic matters were determined by the permangate method modified by the dichromate method, and the rate constant of their biochemical oxidation was determined in hot water extracts of the samples. The need of liming was determined by means of 2 methods. In soil solutions of these samples, all values necessary to evaluate their calcium carbonate equilibriums were determined. The soil samples were enriched with 3% of dry matter of two organic materials, farmyard manure and meadow clover meal, and were incubated at 25&deg;C for 180 days under wetting above 50% of their retention water capacity, and after this procedure all analyses were repeated. Both methods were found to increase the need of liming in all three soils: the more labile the organic matter in 3% addition, the higher the need. The meadow clover matter was more labile than the farmyard manure matter. All three methods for the study of soil carbon lability yielded similar results while the potassium permanganate method was more sensitive than the dichromate one. Increases were observed in equilibrium [Cr(H<sub>2</sub>CO<sub>3</sub>* )] and in Langelier saturation index I<sub>s</sub>. This means that soil liming cannot be considered only as an adjustment to the soil acidity and supply of calcium to plants to meet their requirements, but also as a replacement of the spontaneous adjustment to calcium carbonate equilibrium of soil water, for which through mineralisation of labile organic matters in conditions of our experiment about 220 kg CaCO<sub>3</sub> per hectare of land were consumed on condition that it was not necessary to re-establish it. The process of Ca-compound consumption to establish the calcium carbonate equilibrium is controlled exclusively by the degree of mineralising organic matters lability while the influence of soil properties is only marginal. The same results were provided by the comparison of calcium carbonate equilibriums in nine &Scaron;umava brooks of the total watershed area 78 564 km<sup>2</sup> with the degree of lability of organic matters in their sediments in 1986, 2001 and 2004. A reduction in the intensity of agricultural production in 1986&ndash;2004 resulted in an increase in the stability of organic matters in the sediments, in a decrease in I<sub>s</sub>, and in a lower corrosivity of brooks water towards CaCO<sup>3</sup>. However, the quality of soils and their potential soil fertility decreased due to the loss of labile organic matters.

Effect of sprinkler structure on water distribution uniformity

2012 ◽  
Vol 15 (5) ◽  
pp. 052028
Author(s):  
M Xu ◽  
H Li ◽  
C Chen ◽  
Q Tu ◽  
J P Liu
Keyword(s):  
Water Distribution ◽  
Distribution Uniformity

scholarly journals AVALIAÇÃO DO DESEMPENHO DE SISTEMAS DE IRRIGAÇÃO POR ASPERSÃO CONVENCIONAL FIXO E GOTEJAMENTO EM VILA RURAL

Irriga ◽  
2008 ◽  
Vol 13 (1) ◽  
pp. 47-62 ◽  
Author(s):  
Eguimar Amorim Maciel de Souza ◽  
Paula Cristina de Souza ◽  
Márcio Antônio Vilas Boas
Keyword(s):  
Water Distribution ◽  
Irrigation System ◽  
Field Tests ◽  
Irrigation Systems ◽  
Rural Village ◽  
System A ◽  
De Se ◽  
Distribution Uniformity ◽  
And Storage

AVALIAÇÃO DO DESEMPENHO DE SISTEMAS DE IRRIGAÇÃO POR ASPERSÃO CONVENCIONAL FIXO E GOTEJAMENTO EM VILA RURAL  Eguimar Amorim Maciel de Souza; Paula Cristina de Souza; Márcio Antônio Vilas BoasCentro de Ciências Exatas e Tecnológicas, Universidade do Oeste do Paraná,  Cascavel , Pr, [email protected]  1 RESUMO           O manejo racional da irrigação consiste na aplicação da quantidade necessária de água às plantas no momento correto. É recomendável após a instalação de um sistema de irrigação, proceder-se a testes de campo, com o objetivo de se verificar a adequação da irrigação recomendando, quando necessário, ajustes na operação e, principalmente, no manejo. O propósito deste trabalho foi avaliar dois sistemas de irrigação, sendo um por aspersão convencional fixo e outro por gotejamento,  implantados na Vila Rural Flor do Campo, localizada na região Noroeste do Estado do Paraná, através da determinação dos parâmetros de uniformidade e eficiência de distribuição de água.  Foram utilizadas as metodologias propostas na norma ABNT NBR ISO 7749-2, Asae (1995) e por Keller & Karmeli (1975).   Foram realizados trinta ensaios em cada sistema de irrigação. Para o sistema de irrigação por aspersão foi obtido  CUC  de 77,9%, considerado abaixo do valor mínimo aceitável de 80%, sendo que  a velocidade do vento variou de 0 a 2,4 m s-1. As eficiências de aplicação (Ea) e armazenagem (Es) obtidas neste sistema foram, respectivamente, de 77,0% e 48,8%. No sistema de irrigação por gotejamento foi obtido CUC de 93,7% considerado valor excelente. A Uniformidade de Emissão (UE) encontrada foi de 89,3% sendo considerada boa. As eficiências de aplicação (Ea) e armazenagem (Es) obtidas neste sistema foram, respectivamente, de 100% e 65,0 %. UNITERMOS: Irrigação, aspersão convencional, gotejamento,       uniformidade, eficiência,  avaliação.  SOUZA, E. A. M.; SOUZA, P.C.; VILAS BOAS, M. A. PERFORMANCE EVALUATION OF FIXED CONVENTIONAL ASPERSION AND DRIPPING IRRIGATION SYSTEMS IN  A RURAL VILLAGE  2 ABSTRACT The rational handling of the irrigation consists of the application of the necessary amount of water to the plants at the correct moment. After the installation of an irrigation system, it is recommended the field tests be carried out in order to  verify the adequacy of the recommended irrigation and , when necessary, to adjust the operation and, mainly, the handling. The aim of this work was to evaluate two irrigation  systems,  a fixed conventional aspersion system and a dripping one, installed in the l Flor do Campo, a rural village located in the Northwest of Paraná state, through the determination of the parameters of water distribution uniformity and efficiency. The methodologies used were according to the  ABNT NBR ISO 7749-2 norm, Asae (1995) and for Keller & Karmeli (1975). Thirty assays in each irrigation system were tested. In the irrigation system with  aspersion CUC of 77.9%, which is considered below the minimum acceptable value of 80%, was found  considering that the wind speed varied from   0 to  2.4 ms-1. The efficiencies of application (Ea) and storage (Es) obtained in this system were 77.0% and 48.8 %, respectively. In the dripping  irrigation system, a CUC of 93.7%, considered an excellent value,  was found. The EU was 89.3% and considered good. The efficiencies of application (Ea) and storage (Es) gotten in this system were  100% and 65. 0 %, respectively. KEY WORDS: Irrigation, conventional aspersion, dripping, uniformity, efficiency, evaluation.

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