When crude oil is extracted out of a subterranean reservoir at high temperature and pressure, it is usually transported via a pipeline, where the crude oil experiences radical changes in its physical and chemical properties, instigating numerous complications. Among the various flow assurance problems, wax deposition and build up are among the most commonly found. However, the accurate mechanism of wax deposition is still unclear and is widely debated among researchers. The mechanism under multiphase conditions is also an ambiguity. This review covers the six wax deposition mechanisms, the challenges in multiphase flow conditions, the latest types of chemical inhibitor, and a summary of factors governing chemical inhibitor performance.

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The indoor environmental factors considered in office building must be determined in order to meet user's requirement. Disruption of indoor environment may constitute to reduce occupants' efficiency and work productivity. Therefore, Post-occupancy Evaluation (POE) is a prominent tool that able to indicate satisfaction and comfort level needs by building occupants as lessons learned to identify problems in indoor environment. By using occupants as benchmark of evaluation, the potential of improving the indoor environment in buildings is enormous. With relation to the title, the main purpose of this study is to provide recommendation to improve quality of indoor environment in office building, by analytical study on the level of effort and phases of conducting POE and determining occupant's satisfaction level. The survey used in conjunction with physical measurements to determine how environmental factors affect occupants' perceived comfort and productivity levels, and a benchmarking example of using the survey to establish how new buildings are meeting a client's design objectives. It is recommended that the application of POE is prioritized as strategic level decision making and emphasized as continuous activity in environmental evaluation.

The pipeline system in the oil and gas industry is the heart for transportation of crude and refined petroleum. Nevertheless, continuous exposure of the pipeline surfaces to impurities and sources of corrosion such as sulfur and chromate is totally unavoidable. Vast employment of commercial corrosion inhibitors to minimize the corrosion is being restrained due to toxicity towards the environment. The emergence of “green” chemistry has led to the use of plant extracts and fruit wastes which have proven to be good corrosion inhibitors. This paper aims to provide insight into carrying out further investigation under this research theme for accurate inhibition efficiency measurement.

The general building conditions in low cost housing are part of human's quality indicator. However, there are rising issues on the safety performance of the housing since the occupants are inclined to perceive safety hazards. Therefore, this paper explores the concept of Post Occupancy Evaluation (POE) as safety performance tool. This research conducted a survey on safety performance and occupants' satisfaction to 24 numbers of low cost housing at Kuala Lumpur, Malaysia. The correlation result shows that safety performance has a significant relationship with occupants' satisfaction. The findings supported the application of POE as the tool for safety performance.

The ever-increasing demand for the finite source of oil has led oil production companies to produce and transport the produced crude oil as efficiently and economically as possible. One of the major concerns especially in waters like the South China Sea is the deposition of wax on the walls of the pipeline or wellbore, constricting and hindering the hydrocarbon flow. This is due to the low seabed temperatures, which can be below the wax appearance temperature (WAT), leading to the deposition of wax out of waxy crude oil through the molecular dispersion mechanism. Currently, many prevention and remedy methods are in place to overcome the problem, but most of the additives possess environmental threat, as most of the chemical solutions used are toxic, nonorganic, and costly. Hence, this paper aims to provide some insights into the effect of palm oil derivatives such as crude palm oil (CPO) and crude palm kernel oil (CPKO) on wax inhibition. The effect of aging time (i.e., immersion time) was also evaluated. A comparison was made between paraffin inhibition efficiency results (PIE %) obtained by CPO, CPKO, poly(ethylene- co -vinyl acetate) (EVA), and triethanolamine (TEA). It was observed that the average efficiency of 81.67% was obtained when 1% CPO was added to heavy crude oil. The wax inhibition performance reached a plateau after 1.5 h of aging time for all of the investigated samples.

Matrix-acidizing operations have been accounted to be the most hazardous and environmentally harmful among all the well-stimulation techniques. For instance, diesel oil-based emulsified acids have been prohibited from usage due to their high level of toxicity. There is, therefore, a dire need for emulsified acids that are environmentally viable and technically competent to replace the diesel-based emulsified acids. In this study, a novel oil-based environmental friendly emulsified acid has been synthesized from Jatropha curcas oil and, then, compared against diesel and palm oil-based emulsified acids. The technical evaluation of the three acids has been done based on experimental results obtained from thermal stability, droplet size analysis, rheological study, acid solubility, and toxicity screening. In addition, core flooding experiments have been conducted to evaluate the performance of the three emulsified acids as well stimulants. The results revealed that Jatropha oil-based emulsified acid has the potential to replace diesel-based emulsified acid. Jatropha oil-based emulsified acid was found to perform better than the diesel-based emulsified acid as indicated by having greater thermal stability and more popular rheological properties at varying temperatures of ambient, 50 and 70 °C. Furthermore, it possessed a lower toxicity load and a higher retardation effect on acid solubility than that of the diesel oil-based emulsified acid. The core flooding results have also indicated better well-stimulation performance of Jatropha-based emulsified acid as compared with dieselbased emulsified acids.

Water-based mud is known as an environmental-friendly drilling fluid system. The formulation of water-based mud is designed to have specific rheological properties under specific oil field conditions. In this study, graphene nanoplatelet and silver nanoparticle (nanosilver) were added to a water-based mud formulation in which they act as drilling mud additives. Rheological properties measurements and filtration tests were conducted for evaluating the influence of the added nanoparticles. The results showed that the graphene nanoplatelet and the nanosilver increased the plastic viscosity (PV) by up to 89.2% and 64.2%, respectively. Meanwhile, both the yield point (YP) and the fluid loss values were reduced. In addition, we believe this is the first result ever report where nanosilver is utilized for enhancing-enhanced water-based mud's performance.