Finite element method (FEM) was utilized to determine the natural frequency of two turbine blade materials applicable to Trans-amadi power plant in Port Harcourt, Nigeria. Comparing the two gas turbine blade materials, the fundamental frequency under the same load condition was 751Hz for IN 738 and 896Hz for U500 turbine blade material. This implies that the natural frequencies obtained for both materials were much higher than the operational frequency of 85Hz for resonance to occur. Therefore, resonance would be delayed across the blade materials in service condition, indicating that gas turbine blades designed with both materials would be dynamically stable under operational frequency approaching 745Hz. It was observed that U500 gas turbine blade material which had a higher fundamental frequency has a better mechanical properties that can undergo a longer service condition in extreme working phase before failure compared to IN 738 material. This justification was deduced from the difference between the operational frequency and the fundamental frequency; as the closer the value obtained for fundamental frequency to the operational frequency, the higher the possibility of failure and vice versa. To avoid unforeseen failure and downtime in service operation, vibration test should be conducted on routine schedule in order to meet the expected performance of the gas turbine blade.

Pipeline leakage has both economical and environmental effect. This research work is aimed at the design of a pipeline leakage detection system. In this research work, pressure analysis and K-epsilon turbulence model is one of the common turbulence models used by star CCM+ in resolving fluid flow and is used in this simulation. The parameters used were velocity of fluid (crude oil and gas) and pressure. Different velocities (5m/s, 20m/s, etc.) were used to determined increase or drop pressure. The results from the research work show that excessive drop in pressure is as a result of pipeline leakage and this is mostly likely to occur at the highest bent in the pipeline.

 Abstract - We developed and analyzed a Fault Tree Diagram for the production section/line of a soft drink bottling company in Benin City, Nigeria. A number of faults were identified in this study. One of these faults (basic event) had the following characteristic: "Bottle not full with content and has particle inside". Responses were obtained from employees as to the cause of this failure. The probability of occurrence of this event was computed, after comparing with the Kirsten model. On the whole, 20 logic gates (G1 - G20), 14 interconnecting basic events (primary failures: X1 - X14), 9 undeveloped events, (secondary failures: Z1 - Z9), and nine initiating events (H1 - H9), were used to construct the fault tree. The resultant Fault tree was drawn and validated with ten First-order cut-sets. It was a valid path of occurrence of the top events. The probability of occurrence obtained using Boolean algebra and the bottom up algorithm yielded 0.38.

District cooling (DC) systems have recently proven to be more economically and environmentally viable as compared to conventional cooling techniques. In most DC setups, electric centrifugal chillers (ECCs) are installed to provide chilled water (CW) to charge the thermal energy storage (TES) tank or for direct CW supply to the DC network. The operation of these ECC systems consumes most of the electrical power supplied to the entire DC plant; this therefore strengthens the need to conduct a comprehensive environmental assessment in order to quantify the indirect ecological impact resulting from the energy consumed in the ECC system operation. In order to achieve this, a case study was conducted of four ECC systems with a use-life of 25 years installed in a large DC plant in Malaysia. A gate-to-gate life cycle assessment (LCA) methodology was adopted to analyze the environmental performance of the system setup. The result of the study year reveals that April and June account for the ...

For the past three centuries, there has been a very high demand for stainless steel for different applications, due to its corrosion resistance coupled with the good strength and low cost of the metal. Several welding techniques have been adopted in the fabrication of stainless steel, with the choice of welding technique hinged on the desired requirements. Advancement has been made in its dissimilar welding with other metals like aluminum, copper and titanium. While similar welding of stainless steel faces the challenge of weld metal property deterioration, dissimilar welding poses more serious challenges due to the differential in chemical composition and the thermophysical properties of the base metals. A review of the literature reveals that considerable progress has been made in the improvement of the properties of the weld joint by the application of several weld treatment processes. It was discovered that most of the researchers focused on the effect of these weld treatment pr...

In standard district cooling (DC) plants, central chillers produce cold energy for space cooling throughout the district network. In recent times, the integration of the vapor compression system, which includes the functionalities of vapor compression chillers (VCC), and thermal energy storage (TES) tanks in the DC setup, has gained more implementation across the globe. This is due to the possibility of load shifting by using the VCC to produce chilled water for charging the TES tanks during off peak periods. Since the environmental implications of various energy intensive systems are largely determined by the amount of material and energy consumed throughout their life cycle, it is critical to conduct a sustainability assessment of these systems in terms of environmental contributions, and suggest design options to reduce these impacts. A cradle to grave life cycle assessment (LCA) model is created in response to these issues and in order to meet the project’s objectives. The life ...

This study’s primary goal is to evaluate the performance of a large thermal energy storage tank installed in a Gas District Cooling (GDC) plant. The performance parameters considered in this study include thermocline thickness (WTc), Cumulated Charge (Qcum), and Half Figure of Merit (½ FOM). The operation sensor data of a large Thermal Energy Storage (TES) tank was acquired for this analysis. The recorded temperature sensor from the 1st to 7th January and from 12th to 17th October 2019 was considered in this research. GraphPad prism computer software was deployed for analyses, and the temperature distribution data were analyzed to determine the four temperature parameters (hot water temperature (Th), cool water temperature (Tc), cool water depth (C), and slope gradient (S)) using a non-linear regression curve fitting technique and sigmoid Dose Responses function as integrated with the software. At the end of this research, the relationship between the growth of the determined perfor...

The concept of industrial symbiosis have contributed to the achievement of a circular economy—a production and consumption model that promotes sustainability and also benefits countries economically, socially, and environmentally. There exists a variety of literature that highlights several cases of the application of industrial symbiosis in different geographical locations of the world. However, only a few of these studies have investigated its prevalence in Africa. Therefore, the goal of this study is to analyze the few cases of industrial symbiosis in Africa, highlight the current status, the current regulatory context, the challenges to the implementation of this model, and propose new paths for industrial symbiosis in Africa. The study carried out shows that there exists good potential for industrial symbiosis to thrive in Africa, owing to the type of economic activities and the waste generated in Africa. It also shows that if industrial symbiosis is implemented on a larger sca...