Abarasi Hart

A review of technologies for transporting heavy crude oil and bitumen via pipelines

Heavy crude oil and bitumen resources are more than double the conventional light oil reserves worldwide. Heavy crude oil and bitumen production is on average twice as capital and energy intensive as the production of conventional oil. This is because of their extremely low mobility due to high viscosity at reservoir conditions alongside the presence of undesirable components such as asphaltenes, heavy metals and sulphur making it more challenging to produce, transport as well as refine. It is well know that pipelines are the most convenient means of transporting crude oil from the producing field to the refinery. However, moving heavy crude oil and bitumen is extremely challenging because of their inability to flow freely. As such, without prior reduction in the heavy crude oil and bitumen viscosity, transportation via pipeline is difficult. This is because of the huge energy (i.e. high pumping power) required to overcome the high-pressure drop in the pipeline due to their high viscosity at reservoir conditions. To reduce this high-pressure drop and cost of transportation, several technologies have been proposed to improve the flow properties of the heavy crude oil and bitumen through pipelines. In this study, different technologies are reviewed and the advantages and disadvantages of each technology are highlighted with the view that the review will provide direction for improvement and development of novel technologies for bitumen and heavy oil transportation via pipelines.

Effect of Particle Size on Detergent Powders Flowability and Tabletability

Detergent powders are sometimes processed into compact tablets for cleaning purposes based on the advantage of dosage, minimised dusting and packaging its offers over their powder counterpart. The flow-ability greatly influences handling. The particle size within the powder plays a key role on handling, flow-ability and the strength of the produced compact detergent tablet. The Ariel powder used in this study was separated into different size ranges via sieving; thereafter flowability, compression and compaction were carried out. The compressibility of the powder under 2 KN compaction force was analysed using Heckel equation. It was found that at the same compaction pressure, smaller size particle powders formed compact of greater tensile strength than larger particle. However, the powder with size range of 125-180 μm showed higher flowability compared to other size range.

An overview of transesterification methods for producing biodiesel from waste vegetable oils

ABSTRACT Compared to petroleum diesel, biodiesel is biodegradable and non-toxic. The use of edible vegetable oils for biodiesel production competes with the need for foodstuff. The continuously rising price of edible vegetable oils makes them uneconomical as a long-term biodiesel source. Waste vegetable oils are considered environmental pollution, despite being a potential raw material for biodiesel production, as well as cheap and readily available. Transesterification of vegetable oil is carried out to produce biodiesel in the presence of a catalyst. The catalyst can be homogeneous, heterogeneous, nanoparticles, or enzymatic. Homogeneous catalysts are considered more effective compared to their heterogeneous counterparts, because of reduced mass transfer limitations and high conversion. However, the challenges of separation and purification of biodiesel produced from homogeneously acid/base-catalyzed transesterification of vegetable oils has shifted attention to non-catalytic supercritical methanol/ethanol. It has been reported that at a reaction temperature of 350°C, with a methanol/oil molar ratio of 42, and in the short time of 400 s, 95% conversion is achievable under supercritical methanol. This study explores and presents the advantages and disadvantages of the biodiesel production processes in addition to the effect of the process variable, and also shows the key data set not presently available that would enhance commercialization and economics and improve biodiesel production.

The Impact of Dry Granulation on Detergent Powder Properties

Physical properties of detergent powders can significantly affect process efficiency during conveying, filling, and storage. Poor flow and mechanical properties are generally attributed to such processing problems as sticking, caking, arching and dusting, which cause unplanned redesign of process equipments, low yield and high processing cost. In this study, the feasibility to improve the flowability, compressibility and compactibility of detergent powders through dry granulation was explored. Professional Ariel® regular detergent powder with biological action was chosen as the model material (the feed powder). The feed powder was roll compacted with roll gaps of 1 mm and 1.2 mm at various roll speeds to produce ribbons that were subsequently milled into granules using a cutting mill. The flowability of the feed powder and granules were assessed using a ring shear cell tester. In order to explore the compressibility and compactibility of the feed powder and granules, uniaxial compaction and diametrical compression were also performed. It was found that the flowability of the granules are slightly poorer than that of the feed powder due to wider size distributions, irregular shapes and increased moisture contents resulted from the breakage of capsules containing liquid perfumes in the formulation during roll compaction. It was also found that at smaller roll gap corresponding to higher roll compaction pressure the tensile strength of the produced granules were lower than that of the feed powder, due to the loss of compressibility through roll compaction. It has been shown that the porosity is a critical factor determining the tensile strength of powder compacts.