Troubleshooting Gas Compression Systems Using Data Analysis

The objective of this paper is to showcase the successful and innovative troubleshooting data analysis techniques in one of the gas compression systems in upstream gas oil separation plants (GOSP-A). The gas compression system using gas compressors, dry gas seal systems and due point controls is used in almost all of upstream operation. These proven data analysis techniques were used to tackle major and chronic issues associated with gas compression system operation that lead to excessive flaring, mechanical seal failures, solidification, hydrate formation and off-specification products. Dry Gas mechanical seals are an important key element in gas compression and its lifetime represents a concern to the operation personnel. Most gas compression systems have a mechanical seal lifetime of 2 years which in some cases limit production, increase the potential of unnecessary flaring and increase OPEX significantly. In addition, solidification due to constant liquid carry over result in a wide range of undesirable results such as blockages that constrain production rates and result in safety concerns. In this paper, comprehensive data analysis of the potential root causes that aggravate undesired premature mechanical seal failure, material solidification, equipment damage and off-specification gas products will be discussed along with solutions to minimize expected impact. For example, improper product specification in some applications have been found to promote seal failures, corrosion, solidification and incur additional flaring which is both costly and environmentally undesirable. In addition, after extensive analysis improper operation practices during compressor startups, steady state operation and gas conditioning have been linked with premature compressor failures, product off spec and safety device failures. The field trial proved the effectiveness of the proposed innovative troubleshooting data analysis techniques in reinstating the gas compression unit in GOSP-A to its recommended design conditions, eliminated compressors and mechanical seal failures and avoided the off-specification products at the lowest operating cost. This innovative technique was based on deep and extensive process data analysis, evaluating operating and design data, reviewing international standards, benchmarking against other facilities, process simulation using Hysys, and finally the actual field trial.

A dual pressure indicator, two-layer compression system for treatment of venous leg ulcers: a review

Objective: Venous leg ulcers (VLUs) are considered the most frequent category of hard-to-heal limb ulcers. Although evidence-based care of VLUs suggests that compression therapy plays a pivotal role in the standard of care, patient adherence is considered low, with at least 33% non-compliance, either due to perceived problems from clinicians regarding their own competency in applying the bandages, or from the patient finding the wrapping bothersome. For many years, four-layer bandaging has been considered the ‘gold standard’, but application can be difficult and may also prove uncomfortable for patients. Accurate application may be facilitated by a stretch indicator which has been engineered to act as a surrogate for appropriate pressure application that can address the skill concern, while fewer layers can save clinicians' time and improve the quality of life of patients. Here, we review the literature supporting a two-layer system which combines elastic (long stretch) and inelastic (short stretch) components as well as both layers having graphic markers to define that the dressing has been applied at the proper tension. Method: An initial search was conducted on PubMed and then followed up by a manual search of Google Scholar to retrieve evidence of different levels, in order to evaluate the outcomes of use of the specific two-layer compression system with pressure indicators in the management of patients presenting with VLUs. Results: A total of four papers discussing the specific compression system in question were identified from 32 publications retrieved from PubMed, while a further six were retrieved from Google Scholar. These 10 publications were considered relevant to the two-layer system and were analysed for the outcomes of care, including wound healing, appropriate application, time-saving and better patient acceptance and adherence. Conclusion: Previous authors have demonstrated that two-layer systems are equivalent to four-layer systems. However, the ability to reproducibly apply appropriate compression has remained a question. The papers reviewed demonstrate that evidence suggests that the two-layer compression bandage system with indicators provides continuous, consistent and comfortable treatment that may be easier to apply with accurate pressure levels due to their indicator systems, and therefore, is a procedure that may increase patient adherence and acceptability to the wound therapy.

Analysis of supplemental dehumidification for increased energy efficiency of shoulder seasons based on climate change predictions in Austin Texas

This research project compared a standard vapor compression system and a standard desiccant dehumidification system with heat wheel to determine if there was some potential energy savings for “shoulder season” hours in Austin Texas. “Shoulder season” hours as defined in the paper are hours during which the dry bulb temperature falls within the American Society of Heating Refrigeration and Air Conditioning Engineers (ASHRAE) comfort bound but the humidity is above the comfortable humidity point. These hours are normally addressed with vapor compression systems which dehumidify by cooling the air under the comfort setpoint to dehumidify, which is wasteful of energy. The study found that for these shoulder season hours a desiccant dehumidification system was around 4.5 times more energy efficient at reaching comfort setpoints if free heating was used for drying the desiccant.

Color image compression based on spatial and magnitude signal decomposition

<p>In this paper, a simple color image compression system has been proposed using image signal decomposition. Where, the RGB image color band is converted to the less correlated YUV color model and the pixel value (magnitude) in each band is decomposed into 2-values; most and least significant. According to the importance of the most significant value (MSV) that influenced by any simply modification happened, an adaptive lossless image compression system is proposed using bit plane (BP) slicing, delta pulse code modulation (Delta PCM), adaptive quadtree (QT) partitioning followed by an adaptive shift encoder. On the other hand, a lossy compression system is introduced to handle the least significant value (LSV), it is based on an adaptive, error bounded coding system, and it uses the DCT compression scheme. The performance of the developed compression system was analyzed and compared with those attained from the universal standard JPEG, and the results of applying the proposed system indicated its performance is comparable or better than that of the JPEG standards.</p>