Numerical Description of Jet and Duct Ventilation in Underground Garage after LPG Dispersion

Contamination of toxic and odorous gases emitted from stacks in buildings located in an urban environment are potential health hazards to citizens. A simulation using the computational fluid dynamic technique may provide detailed data on the flammable region and spatial dispersion of released gases. Concentrations or emissions associated with garage sources and garage-to-house migration rates are needed to estimate potential exposures and risk levels. Therefore, the aim of the study was to use an original mathematical model to predict the most accurate locations for LPG sensors in an underground garage for vehicles powered with LPG. First, the three-dimensional geometry of an underground garage under a multi-family building was reconstructed. Next, two types of ventilation, jet and duct, were considered, and different sources of LPG leakage were assumed. Then, the Ansys Fluent software was applied as a solver, and the same initial value of released LPG (5 kg) was assumed. As a simplification, and to avoid the simulation of choked outflow, the emission from a large area was adopted. The results showed stagnation areas for duct ventilation in which gas remained for both the jet and duct ventilation. Moreover, it was observed that the analyzed gas would gather in the depressions of the ground in the underground garage, for example in drain grates, which may create a hazardous zone for the users of the facility. Additionally, it was observed that for jet ventilation, turbulence appearance sometimes generated differentiated gas in an undesirable direction. The simulation also showed that for blowing ventilation around the garage, and for higher LPG leakage, a higher cloud of gas that increased probability of ignition and LPG explosion was formed. Meanwhile, for jet ventilation, a very low concentration of LPG in the garage was noticed. After 35 s, LPG concentration was lower than the upper explosive limit. Therefore, during the LPG leakage in an underground garage, jet ventilation was more efficient in decreasing LPG gas to the non-explosive values.

Hazardous area classification for wheat flour processing plant

Dust explosion possibly occurs in common unit operations such as mills, grinders, dryers, and other modes of transport. The basic element for the setting of hazardous zone types consist of identifies release sources, determination of classification region of hazardous area, overviewing the basic operation in wheat flour processing plant with their specification requirement and use of a suitable code or calculations to determine area scope. Therefore, this analysis can be more elaborate by classifying the hazardous area into several areas using the International Electro Technical Commission System for Certification to Standards Relating to Equipment for Use in Explosive Atmospheres standard. Thus, wheat flour processing plant area classification can be categorized according to three zones based on the quantity of an explosion into atmosphere and its release frequencies which are zones 20, zones 21, and zones 22. From the results, it can be summarized that zone 20 is almost inside or closer one with the main equipment located near the ignition source which could lead to dust explosion, whereas zone 21 and zone 22 comes after zone 20 which is a less hazardous area as compared to zone 20 areas.

New Well Intervention Means as an Answer to Offshore Minimalist Platform Concept: A Breakthrough from Mahakam, Indonesia

Nowadays oil and gas industry are encouraging the independents and majors to take a fresh look at the technology and concepts required to develop marginal shallow water fields using a minimal platform approach. Innovation on well intervention means (lighter, smaller and less footprint) that fit for Offshore Minimalist Platform (OMP) is needed, including optimizing time and cost during well intervention activities in OMP. To achieve the objectives, well intervention innovation and technology are the main focuses. Intervention activities commonly done on campaign basis with several units (slickline, wireline, coiled tubing, testing) shall be integrated in a safe manner. The approach of integration shall signify these points:Identifying potential jobs in OMP to be done by well intervention methodsIdentifying necessary well intervention means and methods to support the jobs (combo unit, micro coil, hazardous zone redefinition, remote operation)Creating project planning and schedulingPerforming site visit and risk assessmentImplementation and operational executionEvaluation of overall project execution result The following results were obtained after the integration performed:No major safety issues during operationExemplary method and risk assessment for well intervention activities which can be applied for next campaignsTrials on well intervention new units and method (combo unit, micro coil, hazardous zone redefinition, remote operation), were safely performed with some optimization100% success ratio60% on supply boat arrangement35% efficiency in N2 consumption for CT operation45% efficiency in diesel consumption20% - 40% efficiency in Rig Up Time28% less in Job Cost compared to conventional unit These innovations are proven as reliable method to answer OMP challenges with main advantages on footprint and cost optimization. Through this paper, we would like to share lucrative well intervention breakthrough and innovation in OMP with measurable milestones.

Slinger Personal Protection System at Load-Lifting Mechanism Operation Employing Radio-Frequency Identification Devices

The rapid implementation of information technologies into all strata of the civil society activities has already significantly modified lives of every citizen, including production processes. The usual practice is using electronic safety devices in the technical units, including hoisting cranes. The consumer market offers remote control systems for equipment; continuous video surveillance over workflows is widely employed. Unmanned productions and unmanned technologies are being implemented, which is especially relevant at operation of potentially harmful and hazardous units. However, for a human actively participating in workflows, control and maintenance of technical devices, his/her safety during fulfillment of working functions is still a matter of great importance. In Russia, the requirements to production employees safety are determined by legislative and regulatory documents in the sphere of labor protection. Special rules of industrial safety are applied to hazardous production facilities. An important aspect of slinger protection against hazardous and harmful factors of production during operation of a hoisting crane as well as observing production discipline is using personal protection equipment and special working clothes. The constant monitoring of safety requirements in order to ensure their implementation in the real-time mode via the RFID-tags integrated into the elements of personal protection equipment and special working clothes is substantiated. The information on slinger location and availability of the required protection equipment within the hazardous zone of hoisting crane operation received to a mobile device of a person responsible for safe operation enables control of the situation, prevention of adverse events and minimization of risk of injury.

Multidisciplinary analyses for mapping and evaluating kinematics and stress/strain field at active faults and fissures at NE Rift, Mt Etna (Italy)

<p>Strategies for disaster risk reduction in volcanic areas are mostly driven by multidisciplinary analyses, which offer effective and complementary information on complex geomorphological and volcano-tectonic environments. For example, quantification of the offset at active faults and fissures is of paramount importance to shed light on the kinematics of zones prone to deformation and/or seismic activity. This provides key information for the assessment of seismic hazard, but also for the identification of conditions that may favor magma uprising and opening of eruptive fissures.</p><p>Here we present the results of a study encompassing detailed geological, structural and seismological observations focusing on part of the NE Rift at Etna volcano (Italy). The area is situated at an elevation ranging between 2700 and 1900 m a.s.l. where harsh meteorological conditions and difficult logistics render classical field work a troublesome issue. In order to bypass these difficulties, high-resolution (2.8 cm) UAV survey has been recently completed. The survey highlights the presence of 250 extension fractures, 20 normal fault segments, and 54 eruptive fissures. The study allows us to quantify the kinematics at extensional fractures and normal faults, obtaining an extension rate of 1.9 cm/yr for the last 406 yr. With a total of 432 structural data collected by UAV along with SfM photogrammetry, this work also demonstrates the suitability of the application of such surveys for the monitoring of hazardous zone.</p>

Numerical Simulation of Emergency Release of Liquid Petroleum Gas on a Car Gas Station

LPG storage tanks may be seriously threatened by a fire coming from nearby fuels or by leakage appearance. The aim of the study was to prepare a three-dimensional model of LPG release on a car gas station under different environmental conditions. CFD simulations of liquid and gas phase release from a tank localized on a car gas station was performed. First, ALOHA software was applied to determine mass flow rate, while Ansys software was used to determine the shape and size of hazardous zone. To reflect real condition atmospheric stability classes were applied. It was observed that for classes A-D the hazardous zone was decreasing. While, for E and F class the range was increased. It was noticed that the location of the leakage affects the extent of the danger zone. For the leaking below the liquid surface analyzed LPG has liquid form. While, for the leaking above the liquid surface analyzed LPG has gas form. Furthermore, for liquid leakage the largest hazard zone of release was observed.