Redundant Photo-Voltaic Power Cell in a Highly Reliable System

The conversion of solar energy into electricity makes it possible to generate a power resource at the relevant location, independent of the availability of the electrical network. The application of the technology greatly facilitates the supply of electricity to objects that, due to their location, cannot be connected to the electrical network. Typical areas of use are nature reserves, game management areas, large-scale agricultural areas, large-scale livestock areas, industrial pipeline routes, water resources far from infrastructure, etc. The protection of such areas and assets and the detection of their functionality are of particular importance, sectors classified as critical infrastructure are of paramount importance. This article aims to show the conceptual structure of a possible design of a high-reliability, redundant, modular, self-monitoring, microcontroller-controlled system that can be used in the outlined areas.

An Alternative Corrosion Risk Assessment Method for Industrial Pipelines in Natural Gas Purification Plant

Natural gas is a kind of high-quality and low-carbon energy and its demand is increasing rapidly year by year. The natural gas produced from the gas well contains some corrosive impurities like CO2, H2S, and H2O. Therefore, the gas needs to be purified in purification plants before it can be used. In the process of purification, the impurities in the natural gas will cause corrosion to the purification equipment, especially to the industrial pipeline, which will lead to perforation and leakage of the pipeline, and even cause poisoning, fire or explosion, and other serious safety accidents. In order to ensure the safe operation of the industrial pipeline in the purification plant, it is necessary to carry out effective inspection and maintenance measures for the pipelines. The traditional regular inspection method just inspects a certain proportion of the pipelines which are selected by on-site inspection personnel. But limited by technical level and work experience of the inspection personnel, some high-risk pipelines may be neglected. Therefore, some plants try to adopt risk-based inspection (RBI) to carry out a risk assessment and conduct a comprehensive inspection on high-risk pipelines, so as to improve inspection efficiency and reduce inspection cost. However, in practice, it was found that the pipeline risk levels are not in accordance with the actual inspection results. The reason is that the RBI method developed in the background of oil refining and chemical industry is not suitable for natural gas purification plants. In order to solve the problems, this paper analyzed the relationship between the influencing factors and pipeline corrosion behavior. The influencing factors include the impurity contents (CO2, H2S, H2O, and chlorides), pipeline materials (carbon steel and austenitic stainless steel), and service conditions (operating temperature, operating pressure and flow velocity). Meanwhile, the plant management status and maintenance factors were also considered as the influencing factors to pipelines. According to the analysis, a corrosion risk assessment method for the pipelines in the natural gas purification plant was developed based on fault tree and scoring method. Finally, the method was applied to the pipelines in purification plant to verify the accuracy of this method.

In Situ Verification of Numerical Model of Water Hammer in Slurries

This paper presents a numerical model of transient flow in a pressure slurry pipeline network with verification based on in situ measurements. The model, primarily verified in laboratory conditions, has been extended and applied to the case of a large and complex slurry pipeline network in Poland. In the model, the equivalent density concept was applied. In situ experiments were performed for various unsteady flow episodes, caused by different pump operation strategies in the industrial pipeline network. Based on the measurements of slurry concentration and pressure variations, the numerical model was tested and verified. A satisfactory coincidence between the calculated and the observed pressure characteristics was achieved. Additional numerical tests led to important conclusions concerning safe pump and valve operation and system security threats.

Influence of hydrate formation and wall shear stress on the corrosion rate of industrial pipeline materials

In the modern systems of transportation of oil, gas and condensate, in the units of regasification of liquefied natural gas, two-phase flows play an increasingly important role in technological equipment used in the chemical and oil refining industry, power engineering and other industries. All available studies on the formation of gas hydrates were mainly focused on their ability to clog pipes along their entire length. While their ability to cause (initiate) corrosion remains virtually unexplored. Therefore, to increase the efficiency of industrial pipelines it is necessary to study the joint effect of hydration formation and stresses of friction on corrosion of the pipeline. The mathematical model of pipeline corrosion has been further developed by considering the influence of the gas hydrate. The influence of pressure, temperature on the speed of corrosion processes is estimated and it is shown that under the most unfavorable conditions the corrosion rate under the action of gas hydrates can increase several times.