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The purpose of this paper is to explore the process, and analyse the implementation of constructability improvement and innovation result during the planning and design for seawater intake structure of fertilizer plant project.

The research methodology approach is case study method at the project level. This constructability improvement process was investigated by using constructability implementation checklists, direct observation, documented lessons learned analysis and key personnel interviews.

The case study shows that the implementation of constructability during planning and design stage for this seawater intake structure has increased the project performance as well as improved the schedule by five months (14.21 percent) and reduced the project cost by 15.35 percent.

This case study was limited to three previous seawater intake projects as references and one new method seawater intake structure at a fertilizer plant project.

A constructability improvement checklist using theory and lessons learned for the specific construction project was documented.

The findings support the relevant study of constructability and provide specific lessons learned for three previous projects and one of the new methods of the construction project and which are documented by the company.

This paper aims to determine the optimum arrangement of a reverse osmosis system in two methods of plug and concentrate recycling.

To compare the optimum conditions of these two methods, a seawater reverse osmosis system was considered to produce fresh water at a rate of 4,000 m3/d for Mahyarkala city, located in north of Iran, for a period of 20 years. Using genetic algorithms and two-objective optimization method, the reverse osmosis system was designed.

The results showed that exergy efficiency in optimum condition for concentrate recycling and plug methods was 82.6 and 92.4 per cent, respectively. The optimizations results showed that concentrate recycling method, despite a 36 per cent reduction in the initial cost and a 2 per cent increase in maintenance expenses, provides 6 per cent higher recovery and 19.7 per cent less permeate concentration than two-stage plug method.

Optimization parameters include feed water pressure, the rate of water return from the brine for concentrate recycling system, type of SW membrane, feedwater flow rate and numbers of elements in each pressure vessel (PV). These parameters were also compared to each other in terms of recovery (R) and freshwater unit production cost. In addition, the exergy of all elements was analyzed by selecting the optimal mode of each system.

Underground cast iron and steel pipelines are used for the conveyance of potable water for domestic supply and steel pipelines are used to transport fresh water in fire water mains in both installations onshore and on offshore oil and gas platforms. Seawater is conveyed by pipeline for industrial cooling applications.

Introduction The degree of adsorption of organic inhibitors on a metal surface in presence of halide anion is predominantly influenced by the synergistic effect. The synergistic effect brings about an improvement in inhibition as a result of chemisorption or physical adsorption depending on the nature of the interaction between the halide and the cation of the inhibitor. This effect is partly attributed to the stabilization of the adsorbed anion layer by an organic cation through a possible covalent linkage. The degree of availability of electrons influences the mode of adsorption. Investigations on ferric ion corrosion have shown that the synergistic inhibition effects the corrosion processes by primarily increasing the polarization of the cathodic reaction. The adsorption of quinoline on 18–8 steel in the presence of halider ions is predominantly influenced by the synergistic effect. It has been found that the addition of smaller concentration of quinoline inhibits the cathodic reaction and higher concentrations of quinoline inhibit the anodic reaction as well. According to Iofa the formation of an adsorbed layer of positively charged ion retards the transfer of cation through a binary layer and lowers the transfer rate. Work on amines has shown that tertiary and secondary amines are stronger than the primary amines as a result of increase of dipole moment of the doublet, increase of ionisation energy and increase of polarizability. Basicity and stearic effects, both are important. The high effectiveness of cyclic amines with more than seven carbon atoms appears to be correlated with the character of the free electron. It has been shown that whereas the organic compounds of cationic type were weakly absorbed on the iron surface in H2SO4 the addition of halides produced a considerable increase in the adsorption. Cavallaro and others have shown that several nitrogen molecules inhibit both the anodic and cathodic reactions.

The main aim of this study is to determine the fracture toughness and accordingly to predict the fracture initiation, crack propagation and mode of crack extension accurately in polypropylene subsea pipes subjected to internal pressure.

Tensile test was performed following the ISO 527–1 standard. An elastic-plastic constitutive model was developed based on the tensile test results, and it is implemented in the FEA model to describe the constitutive behaviour of the polypropylene material. Three-point bend tests with linear-elastic fracture mechanics (LEFM) approach were conducted following ISO-13586 standard, from which the average fracture toughness of the polypropylene pipe material in crack-opening mode was found as KIc = 3.3 MPa√m. A numerical model of the experiments is developed based on the extended finite element method (XFEM), which showed markedly good agreement with the experimental results.

The validated XFEM modelling approach is utilised to illustrate its capabilities in predicting fracture initiation and crack propagation in a polypropylene subsea pipe subjected to an internal pressure containing a semi-elliptical surface crack, which agrees well with existing analytical solutions. The XFEM model is capable of predicting the crack initiation and propagation in the polypropylene pipe up to the event of leakage.

The methodology proposed herein can be utilised to assess the structural integrity and resistance to fracture of subsea plastic pipes subjected to operational loads (e.g. internal pressure).

As a result of the increasing costs of protecting conventional pipes a number of alternative pipe materials have been introduced in the last two decades with considerable emphasis on plastics. Thus a range of thermo‐plastics such as PVC or Polyethylene have been used for both pressure and non pressure applications in the smaller diameters but the most significant addition to the range of pipe materials has been that of fibre reinforced composites particularly glass fibre reinforced plastics (GRP).

Natural gas (NG) consumption is increasing at an alarming rate, and more than 50 percent of this gas is used in generating electric power (EP) and desalted seawater (DW) in what is called cogeneration power desalting plants (CPDP). In this context, the purpose of this paper is to study the energy status in Qatar. More specifically, Qatar energy supply side is studied through the CPDP. In an effort to decrease the energy consumption by raising the efficiency of the CPDP (at the supply side), and conserving energy at the demand side, primarily energy footprint is performed.

The status of CPDP, in terms of the type, capacity, fuel consumption is studied, and measures that should be taken to improve their performance and reduce their consumed fuel are presented.

Study of the EP and DW sector showed that the fuel consumed in the CPDP can be reduced substantially by converting the simple gas turbine cycle to combined cycle to raise its efficiency from 30 percent to up to 50 percent. On the demand side, it was shown that air conditioning (AC) of buildings consumes about two‐third of the summer peak load; and about half of the annual EP output. So, measures to decrease the AC cooling load are suggested by implementing building code to decrease the consumed energy in buildings.

Data on the NG and oil proven reserve, production, and consumption are limited and scattered. It is necessary to have a clear picture of Qatar showing the flow of energy supply, demand, consumption, and losses in certain sectors to know where energy can be conserved; and this paper is the first trial in that direction. Although prime energy looks abundant today, it can be consumed locally within few decades if consumption is not controlled.

This paper aims to examine the reliability of a cooling seawater pumping station which pumps seawater to refineries and petrochemical plants in Kuwait mainly for cooling purposes. Owing to the harsh operating climate and the lack of other alternative sources of water, high reliability of the pumping system is crucially important.

The reliability of a system can be considered from different views. The one taken in this study is to measure the reliability of the cooling seawater arriving to the consumer at the required pressure and flow rate while observing the operational constraints on the system. A reliability model has been developed and applied to the actual data from the pumping station.

The preliminary results indicate that the model could be a useful tool to assess the current condition of the system and to find ways of improving system reliability and availability.

The paper provides information of value to all concerned with relibility management.

The utilisation of renewable energy sources for generating electricity and potable water is one of the most sustainable approaches in the current scenario. Therefore, the current research aims to design and develop a novel co-generation system to address the electricity and potable water needs of rural areas.

The cogeneration system mainly consists of a solar parabolic dish concentrator (SPDC) system with a concentrated photo-voltaic module at the receiver for electricity generation. It is further integrated with a low-temperature thermal desalination (LTTD) system for generating potable water. Also, a novel corn cob filtration system is introduced for the pre-treatment to reduce the salt content in seawater before circulating it into the receiver of the SPDC system. The designed novel co-generation system has been numerically and experimentally tested to analyse the performance at Karaikal, U.T. of Puducherry, India.

Because of the pre-treatment with a corn cob, the scale formation in the pipes of the SPDC system is significantly reduced, which enhances the efficiency of the system. It is observed that the conductivity, pH and TDS of seawater are reduced significantly after the pre-treatment by the corncob filtration system. Also, the integrated system is capable of generating 6–8 litres of potable water per day.

The integration of the corncob filtration system reduced the scaling formation compared to the general circulation of water in the hoses. Also, the integrated SPDC and LTTD systems are comparatively economical to generate higher yields of clean water than solar stills.

Here, attempts have been made to explore the possible use of Marine waste as filler materials into the bio-fibre composites. Clam shell is a type of marine waste which belongs to the class of Bivalvia. It is mainly made of aragonite crystalline polymorphs. This paper aims to develop a new class of natural fibre composite in which jute fibre as reinforcement, epoxy as matrix and clam shell, as particulate microsphere filler. The study investigates the effects of different amounts of clam shell powder on the kinetics of water absorption of jute fibre-reinforced epoxy composite. Two different environmental conditions at room temperature, i.e. distilled water and seawater, are collected for this purpose. Moisture absorption reduces when clam shell is added to the jute-epoxy composite. The curve of water absorption of jute-epoxy composites with filler loading at both environmental conditions follows as Fickian behaviour.

Hand lay-up technique to fabricate the composite – Experimental observation

The incorporation of Clam shell filler in jute epoxy composite modified the water absorption property of the composite. Hence the present marine waste is an potential filler in jute fibre reinforced polymer composite.

The paper demonstrates a new class hybrid composite material which uses a marine waste as important phase in the bio-fibre-reinforced composite. It is a new work submitted for original research paper.