Fouling in Heat Exchangers

A major problem in industries that use heat exchanger equipment cooled with water in their industrial processes is biofouling. In the design and operation of heat exchangers cooled with water, a coefficient of biological must be considered, which affects the efficiency of the equipment. For this reason, it is necessary to apply appropriate antifouling treatments to the design of each heat exchanger. In order to minimize the undesirable phenomenon of biofouling, various mitigation methods have been developed over the last 30 years, both online and offline, of a physical, chemical, or biological nature. Most of these methods are well contrasted and are applied in the regular operation of the facilities, although some methodology approaches are in the research and development phase. However, the application of most of these methods requires interrupting the production, periodically, in order to clean the biofouling, seriously damaging the performance and operation of the installation. The “online” methods to biofouling control are chemical (oxidizing, and non-oxidants), biological and physical treatments. Nowadays, other methodologies of biofouling mitigation that do not affect the environment are being investigated, although, until now, none have been found that are substitutes for chemical agents and that have the same or with higher efficiency

Production of environmentally innocuous coatings

It is known the biofouling phenomenon, as well as the negative consequences that it means for the artificial structures in contact with seawater in form of structural defects and of additional expenses for the companies which develop their work in the marine scope due to the processes of cleaning and prevention, the evolution in the world of the technology of antifouling paintings, once we analysed the serious environmental problems caused by an indiscriminate use of byocides of high toxicity in its composition as they are the organic derivatives of tin compounds made up and of the uncontrolled emission of volatile organic compounds (VOC) to the atmosphere, according to the present environmental norm, has as only aim to develop environmentally innocuous coverings based on water in which extracts of the very same marine world are used as byocides compound

Bioactive ceramic coating solution for offshore floating wind farms

Biofouling is a natural phenomenon that consists of the accumulation of living organisms on an artificial surface submerged or in contact with water like Offshore platforms. This study highlights the need for offshore floating wind farms structures to consider the choice of material used in offshore applications to minimize microbial-associated and corrosion problems. For this purpose, differences in the total of seawater biofouling attached on two coated paints and three ceramic coatings in carbon steel for offshore structures were evaluated and compared. All ceramic coatings were made of incorporating, by electrophoretic deposition, active ceramic particles against biofouling as copper, silver, zinc and titanium. This experiment consisted of testing ceramic coatings and conventional paints in a real environment with high biological activity and at the same time in a shallow marine environment for a period of 1 year, which provided positive comparisons with the standard system (ASTM-D3623) for using in protecting offshore marine structures

Quantitative Changes in Biofilms of a Seawater Tubular Heat Exchanger Subjected to Electromagnetic Fields Treatment

Biofilms adhesion is one of the more important cost of industries plants on wide world, which use to water for cooling heat exchangers or are in contact with water. This study evaluated the effect of Electromagnetic Fields on biofilms in tubular heat exchangers using seawater cooling. The results showed an up to 40% reduction of the biofilm thickness compared to the untreated control tubes. The presence of organic matter was reduced by 75%, the inorganic mater was reduced by 87%, and 53% of the dissolved solids were eliminated. The biofilm thermal conductivity in the treated tube was reduced by 53% as compared to the control tube. The hardness in the effluent during the experimental period was decreased by 18% in the treated tubes compared with control tubes. Our results show that the electromagnetic fields treatment has a great potential in the process of removing biofilms in heat exchanger

The relationship between expenditure on defence and economic growth in Spain

Purpose: The objective of this article is to perform a causality analysis between defence expenditure and the economic growth in Spain from 1960 to 2018. Design/Methodology/Approach: The VAR model together with the Granger causality test has been used so as to study which is the relationship between the military expenditure and the economic growth. In addition, using France as a benchmark, the results obtained, considering the same parameters, are in line with the obtained for Spain. Findings: The results suggest the existence of a causal relation turning from defence expenditure to economic growth. Practical Implications: In contrast with other studies in which no single conclusion can be arrived at concerning the possible positive or negative effects of defence investment on a country's economy, this work has obtained results that can serve to inspire relevant aspects of economic policy. Originality/value: The relationship between defence expenditure and its impact on the growth of the economy has aroused the interest of not only numerous authors, but also of the countries which are trying to get a clear idea of the economic impact of defence spending before choosing to reduce expenses in order to control both the deficit and the public debt.peer-reviewe

Intercambiador de calor portátil para el ensayo de tubos extraibles de diferentes materiales

Intercambiador de calor portátil para el ensayo de tubos extraíbles de diferentes materiales, que comprende: - una pieza hueca abierta por ambos extremos; - al menos dos tubos situados en el interior de la pieza hueca: al menos un tubo de ensayo y al menos un tubo de control ; - al menos una toma de entrada: - al menos una toma de salida; - una placa que comprende tantas aberturas como tubos comprende el intercambiador de calor, situada en cada extremo de la pieza hueca, y que se encuentra unida al extremo de la pieza hueca mediante una pluralidad de elementos de sujeción; - una junta elástica unida a cada placa en su lado en contacto con la pieza hueca mediante una pluralidad de elementos de sujeción; - El doble de racores de presión que tubos comprende el intercambiador de calor, tal que cada racor de presión se encuentra unido a una de las aberturas de las placas, y tal que cada extremo final de cada tubo se encuentra unido a un racor de presión diferente.Solicitud: 201600940 (03.11.2016)Nº Pub. de Solicitud: ES2598122A1 (25.01.2017)Nº de Patente: ES2598122B2 (20.09.2017

Characterization of leakage verification procedures in refrigeration circuits applied to maritime containers

The evolution of portable refrigeration units and the refrigerants used with them has facilitated enormous advances in autonomous refrigerated maritime shipping containers and temperature control. This has permitted the shipping of products with very strict temperature requirements. It is very important to have a correctly designed system in which the amount of fluid is calculated for a specific construction. A mass above design requirements increases the cost of the finished product. If the mass of refrigerant is below design requirements, more energy is required to maintain the target temperature and, therefore, maintenance costs increase. This paper describes a process to test for leaks in refrigeration equipment. This process can assure the tightness of refrigeration circuits against small leaks over their working lives

Dispositivo portátil para la monitorización, ensayo, incorporación de aditivos y control de tuberías, sus materiales y fluidos

Dispositivo portátil para la monitorización, ensayo, incorporación de aditivos y control de tuberías, sus materiales y fluidos, configurado para albergar en su interior una probeta del material de estudio y monitorizar los parámetros de un fluido que circula por su interior proveniente de una instalación o equipo al que se encuentra conectado, que comprende: - un primer elemento consistente en una pieza hueca, donde uno de sus extremos se conecta a la instalación por medio de un racor de conexión con cierre mecánico, donde el extremo restante está abierto y comprende unos medios de unión configurados para unirse a un segundo elemento, y donde en el interior de dicha pieza hueca se aloja una membrana flexible, de material plástico o polímero flexible, mecanizada y empotrada en el contorno interior de la pieza hueca cubriéndolo en su totalidad; - un segundo elemento consistente en una pieza hueca, donde unos de sus extremos está abierto y comprende unos medios de unión configurados para unirse al extremo del primer elemento no conectado a la instalación, y donde dicho segundo elemento comprende conexiones mecanizadas a lo largo de su contorno con el objetivo de conectar sensores.Solicitud: 201700443 (29.03.2017)Nº Pub. de Solicitud: ES2646732A1 (15.12.2017)Nº de Patente: ES2646732B2 (30.07.2018

Reactor para crecimiento de bioincrustación en condiciones controladas

Reactor para el crecimiento de bioincrustación, configurado para reproducir diferentes entornos en condiciones controladas de laboratorio, que comprende: - un depósito abierto por su parte superior; - al menos una abertura de entrada situada en el depósito, tal que durante la realización del ensayo una tubería de alimentación se introduce en la abertura de entrada: - un intercambiador de calor situado en la tubería de alimentación, fuera del depósito; - al menos una abertura de salida situada en el depósito; - una tubería de rebose, situada tal que uno de sus extremos atraviesa la abertura de salida, y su extremo restante se encuentra conectado a un rebosadero; - al menos una abertura de vaciado situada en el depósito, tal que durante la realización del ensayo una tubería de vaciado se introduce en la abertura de vaciado; - una estructura portaprobetas situada en el interior del depósito; - un agitador de paletas; - un sistema de iluminación regulable.Solicitud: 201600942 (03.11.2016)Nº Pub. de Solicitud: ES2601930A1 (16.02.2017)Nº de Patente: ES2601930B1 (16.10.2017

Dispositivo manual y portátil para el enrollado y la deshidratación de mangueras planas

Dispositivo manual y portátil para el enrollado y la deshidratación de mangueras planas, que comprende:- una varilla configurada para que, durante el funcionamiento del dispositivo, ésta gire sobre la base de la varilla, donde la varilla presenta al menos tres tramos, a) un tramo inferior comprendido entre la base de la varilla y un punto de doblado inferior; b) un tramo superior comprendido entre la parte superior de la varilla y un punto de doblado superior; y c) al menos un tramo intermedio comprendido entre los puntos de doblado superior e inferior;- al menos dos dientes situados en la parte inferior del tramo inferior de la varilla, tal que los dientes se unen a la varilla de manera perpendicular y presentan a su vez un curvado hacia la base de la varilla cuyo ángulo está comprendido entre 75º y 95º, tal que los dientes se sitúan equidistantes con respecto a la varilla, tal que los dientes tienen una separación entre sí de 360º/número de dientes, y tal que existe un desfase de medida entre la base de la varilla y la base del diente de al menos 1 centímetro.Solicitud: 201601108 (23.12.2016)Nº Pub. de Solicitud: ES2608844A1 (17.04.2017)Nº de Patente: ES2608844B1 (26.12.2017