Moradi S.,Shahid Chamran University |
Steel and Composite Structures | Year: 2012
In this paper, the thermal buckling analysis of rectangular composite laminated plates is investigated using the Differential Quadrature (DQ) method. The composite plate is subjected to a uniform temperature distribution and arbitrary boundary conditions. The analysis takes place in two stages. First, pre-buckling forces due to a temperature rise are determined by using a membrane solution. In the second stage, the critical temperature is predicted based on the first-order shear deformation theory. To verify the accuracy of the method, several case studies were used and the numerical results were compared with those of other published literatures. Moreover, the effects of several parameters such as aspect ratio, fiber orientation, modulus ratio, and various boundary conditions on the critical temperature were examined. The results confirm the efficiency and accuracy of the DQ method in dealing with this class of engineering problems. Source
De La Fuente J.G.,Repsol |
Capelle J.-Y.,Total S.A. |
Lemmers S.,Vopak |
Frost S.,Repsol |
And 18 more authors.
International Gas Union World Gas Conference Papers | Year: 2015
With natural gas advancing its position in the world energy mix, exploration activity, which has been historically focused on oil, now embraces gas with the same enthusiasm. Today it is the gas discoveries, which are dominating the headlines. Driven by demand, technological advances and viable economics, LNG is allowing the development of gas discoveries in more and more remote and hostile regions of the globe. As exploration moves into these new frontiers, gas liquefaction projects will similarly be located in increasingly distant and hostile areas. Perhaps considered the most hostile region of all, the Arctic Circle provides some of the most challenging projects for LNG today and looks to be one of the biggest growth areas in the coming 20-30 years of exploration. The purpose of this IGU report is to review the new and challenging remote and hostile regions where LNG projects are being planned and could be located in the future, and discuss the particular challenges that are faced in the whole chain from site selection through design and construction to the operation and LNG export from these plants. Whilst Floating LNG (FLNG) can be considered as another remote concept, it was decided to exclude FLNG from this discussion due to the very specific nature of the concept and extensive discussion in other publications or working groups. The term "remote"generally implies a significant distance from a particular place, and it is fair to say that, by definition, the majority of LNG production projects are in geographically isolated areas, as the driving force behind liquefaction projects has always been the need to monetize and transport isolated gas reserves in an economic way to markets, which can be anywhere in the world. However, this report proposes to include other factors into the term "remote" to give a more complete indication of the challenges that are faced by complex projects in complicated areas of the world. Therefore a Remoteness Index has been developed and presented in this report. The Remoteness Index, quantifies just how remote and hostile a particular project is and, based upon past projects experiences, looks at correlations, which may be useful in predicting outcomes and success rates of future projects. Several case studies are discussed of projects that are in operation or are under the planning/construction phase, and specific lessons learned are highlighted. The Remoteness Index does not just measure geographical distance. There are other factors that cause severe challenges in any or all of the planning, design, construction, operations, and export phases, and therefore these are incorporated into the concept of the remoteness of a project. The criteria identifying REMOTE are as follows: - Geographical Remoteness - This refers to the site being a significant distance from any infrastructure, any urban centre and any notable logistical availability. - Extreme climatic conditions - This refers to either constant extreme temperature, significant seasonal temperature swings, or other adverse constant or varying extreme conditions. - Manpower Problems - Severe operational challenges caused by lack of skilled affordable manpower, applicable mainly to the construction phase but also relevant to the operational phase. - Operational Challenges / infrastructure - Access to the site, local content problems through lack of local suppliers. This affects both the construction phase as well as the operational phase. - Technical hurdles - The need for a technical solution drives the development of the technical solution. This criterion rates the projects in relation to the technological challenges faced in the design, construction, and operational phases. - Environmental Sensitivity - By default most remote areas of the world are untouched and considered environmentally sensitive. New projects have an effect on the environment and there is an increasing public resistance to such intrusions. The earliest liquefaction plants were ground-breaking in terms of technology application and provided great leaps forward regarding know-how, and, whilst at the time they were constructed in what were considered out-of-the-way places, today many of the plants are now considered as standard. So, which plants are more remote than others, what makes them more remote and what does the future hold? In order to address this, and be able to have a quantification of remoteness, the previously mentioned factors can be defined and weighted to provide a numerical indication of remoteness. And when statistically analysing LNG Plants it was concluded that the distribution of the Remoteness Index was quite narrow in a band between 3 and 4, which nicely fitted a Gaussian distribution. However, new projects, especially in the United States do not follow the former trend. This is explained by the fact that these new liquefaction plants use a new production scheme (i.e. conversion of existing LNG receiving terminal into a liquefaction plants), are located close to the source of gas (not stranded gas) and are in an area where infrastructure is fully developed. United States shale gas has triggered a series of new projects with surprisingly low Remoteness Indices. The Remoteness Index can be used as an analytical tool to identify historical and future trends, and allows explanation of the historical trends and potential prediction of future trends. This will also be an indication for the complexity of certain remote projects. Major conclusions presented in the extended IGU report for the criteria defining the Remoteness Index are: Geographical and climatic conditions The Arctic Circle offers perhaps the most prolific potential regarding exploration, but at the same time it presents some of the biggest challenges regarding development and export of gas to market. Cold and harsh conditions present a unique set of technical challenges in all phases of the project, including LNG export in carriers with ice-breaking capability. Other locations in Asia-Pacific and in East Africa are likely hard to reach due to geographical isolation and lack of well-developed infrastructure. Severe climatic conditions affect the design of the project and can significantly influence construction activities. All planning cycles should be carefully matched with adequate contingencies for the weather cycles. While infrastructure will develop over the years, adverse climatic conditions cannot be changed by mankind. Thus, this aspect will remain a significant indicator for a competitive sufficient profit generating LNG liquefaction project. Social and environmental issues The majority of remote projects, even though initially located in areas of little or no urbanisation, do affect the socio-political landscape, often leading to development of urbanisation and bringing significant social change. In addition, the social implications of large scale investment projects are increasingly an obligation in the design and planning stage. They carry a large social responsibility towards indigenous habitants. Social responsibility programs need to be part of project execution and operation. Environmental aspect constraints need to be taken into account to minimise impact on marine and wildlife environment, which has not seen industrial development. While people may assimilate to changes in their social and cultural life within decades, the environment needs much longer periods to recover from imprudent disturbances. Short sighted run for profit may cause tremendous expenses to re-establish fair living conditions. Thus, a high rating in the category Environmental Concern needs to be considered seriously, when new projects approach FID. Technical and operational challenges All countries, especially the new LNG players are demanding significant Local Content in projects. Whilst most LNG project shareholders fully support the notion of Local Content, the reality is often a big obstacle in the sanctioning and development of remote projects. Development of these project requirements has a special focus on operation, maintenance, safety, and occupational health. From a design point of view remote projects have special requirements due to soil conditions, ambient conditions like snow and ice or storms, humidity, floods and sun radiation. This results in selecting optimal liquefaction technology, redundancy of equipment to ensure reliability and sometimes extensive winterisation of structures and equipment. Proper planning is critical since construction windows may be limited. Standardisation and modularisation to minimise construction work on site is one of the key success factors of constructing remote projects. However, technology is keeping pace with hostile environment project requirements. No project as yet has been shelved due to purely the lack of technological solutions, but due to the lack of economical sense of the required technological solutions. Cost impact of Remoteness Index From an aprioristic approach it could be expected, that the costs for an LNG project directly correlate to the remoteness (and therefore the Remoteness Index). However by evaluating past projects it is not possible to infer such a relationship exists. While certain remoteness criteria clearly do have an impact on a projects overall costs, other factors also have a very large impact on a particular projects costs (such as: raw materials costs, contractors' workload panorama, projects confluence, and many others). A clear view on the correlation between remoteness and cost looks as likely to be as absent for future projects as has been the case up until now. Usage of Remoteness Index Nevertheless, the Remoteness Index can be taken as an indication about how challenging a new LNG project can be due to its location; in this sense developers of new remote projects, can find it useful to check their new projects Remoteness Index estimate against other past projects with similarities. All of those projects, which have been classified as highly remote (Remoteness Index ≥4.0) and have started up already, are located in hot areas of the Asia-Pacific. Future projects including Yamal LNG and Alaska LNG will go further North and will be more in line with the general perception of remote. Source
Mering W.,Royal Dutch Shell |
Gomes I.,Energix strategies |
Tholen H.,Royal Dutch Shell |
Fiandaca G.,Royal Dutch Shell |
And 19 more authors.
International Gas Union World Gas Conference Papers | Year: 2015
Fifty years ago, the first commercial LNG cargo was shipped from an LNG export facility in Algeria in 1964. Since then, LNG has grown into a truly global commodity. This growth has been accompanied with, and driven by, economies of scale in the design and construction of facilities. Since the first trains in Algeria of 0.4 mtpa LNG, the conventional LNG business has evolved into 7.8 mtpa mega-trains in the 77 mtpa Ras Laffan Industrial City in Qatar In recent years, a comeback of smaller scale LNG facilities has emerged. New liquefaction and distribution facilities are being constructed and operated across the globe. Currently, the global small-scale LNG (SSLNG) installed production capacity is of 20 mtpa spread around more than hundred SSLNG facilities. This is on top of the installed capacity for conventional LNG plants of approximately 300 mtpa. The SSLNG market is developing rapidly, especially as a transportation fuel and to serve end users in remote areas or not connected to the main pipeline infrastructure. This report, written by the IGU Program Committee (PGC) D3, provides an overview of this new and dynamic SSLNG business worldwide. Its objective is to increase awareness and understanding in this area as a basis for an informed discussion on how to further develop this industry. In terms of scope, this study considers the wholesale SSLNG supply chain, including production, liquefaction, transport, reception, break-bulk and regasification. The IGU defines small scale liquefaction and regasification facilities as plants with a capacity of less than 1 mtpa. In turn, SSLNG carriers are defined as vessels with a LNG storage capacity of less than 30,000 cubic metres. The retail LNG business is described in the Program Committee (PGC) D2 report on LNG as fuel, which covers the more user-oriented supply chain, including distribution and end-use. The global commoditisation of LNG has provided a solid base for the emergence of new LNG applications and markets. The key drivers for SSLNG are environmental, economic and geopolitical. The environmental benefits of LNG in terms of CO2, SOx, NOx, and particulate emissions are undisputed when compared to alternative fossil fuels but it also needs to have a transparent and profitable business model to be feasible. The supply chain can be rather expensive due to the diseconomy of the small scale and the relatively small size of the market, but as technology solutions mature, standardisation, modularisation and therefore competitiveness are expected to increase. The lower entrance hurdle compared to large LNG projects opens up opportunities for creativity and fast new technology deployment. Most of the growth is in China where efforts are in place to get clean fuels to fight air pollution in the cities, stimulated by the availability of gas and the price differential between natural gas and diesel. Price arbitrage is also the primary driver in the US with the abundance of shale gas. Stricter regulations on the marine sector are stimulating the use of SSLNG as bunker fuel in Europe (Scandinavia, Baltic and NW Europe). In Latin America, the key drivers are the monetisation of stranded gas supplies and the need to reach remote-located consumers. Significant SSLNG import, break bulk and regasification is already present in China, Japan, Spain, Portugal, Turkey and Norway with hundreds of small terminals and it continues to grow to service remote local areas and fluctuating consumption profiles. The development and maturation of SSLNG technology are key enablers for the pursuit of the SSLNG business. Here, significant progress has been made in all areas across the value chain. In the liquefaction plants, the development and optimisation of a wider range of processes and equipment helped to counter the diseconomy of small scale and to reduce initial investment cost. The application of pressurised LNG tanks provides a more cost-effective means for storing smaller parcels of LNG when compared to the conventional atmospheric flat bottom tanks. It also allows for a more effective way to manage boil-off gas (BOG) and pressure build-up across the value chain, thus eliminating the need for more expensive BOG compression solutions. Developments in shipping (cargo containment systems, commoditisation) and transfer (ship-to-ship transfer, emergency shutdown and release systems) also support the trend towards more fit for purpose solutions in SSLNG. New project execution principles such as modularisation, containerisation, replication and standardisation enable further growth of LNG. Small scale LNG creates opportunities for lean operational and maintenance strategies, i.e. unmanned operation, multi-disciplinary staff, etc. However there are still many challenges. One of the challenges of SSLNG globally is meeting the security of supply and demand, for example to overcome the concern of customers to step into the SSLNG market with only limited supply alternatives available. Some SSLNG opportunities become only feasible with a complete supply chain development, from well to end-customer. The challenge here is to operate and design all elements within such a supply chain effectively and competitively. The development of cost-effective, modularised and standardised supply networks is crucial to overcome this challenge. Another challenge is the implementation of a fiscal regime and a regulatory framework, conducive to investment decisions for SSLNG opportunities. An important consideration is the impact of the recent drop in oil prices in the investment decision for natural gas and LNG projects. This is expected to affect the SSLNG business in particular, due to its fast-responding nature and because these projects require large oil/gas price differentials, that may no longer be available in the current oil price scenario. The development of downstream infrastructure and logistics - remote regas facilities, bunkering and trucking stations - is key for building up a robust market for SSLNG. Historically, LNG has displayed a very good safety track record. The very high reliability and safety level achieved by the traditional LNG industry does not guarantee that the same safety standards can be maintained for the small scale business due to the many differences between the two business models. For example, due to the large number of smaller parcels and multiple players in a rapidly growing market, the SSLNG business is scattered and more challenging to manage. Sharing of best practice, developing consistent national and international safety standards and creating a certified training level for staff involved in SSLNG are needed to maintain the high safety standards of the industry. The expectation for the small scale LNG business is that the expansion will continue towards 2020, growing towards a 30 mtpa business globally. This growth is predicated on the implementation of a level playing field, with economic incentives and robust environmental regulations, on technology developments driving down costs, and on the sustainability of a competitive price spread between natural gas and oil. Source
News Article | January 28, 2016
Now that Western sanctions have been lifted from Iran’s energy sector, the country wants to sell its natural gas (the largest gas reserves on the planet at 1,201 trillion cubic feet) to the world. However, unfortunately for Iran it lacks the necessary infrastructure to quickly enter the market. Alireza Kameli, managing director of National Iranian Gas Export Co. (NIGC) said on Tuesday that the Islamic Republic is exploring several options to help join the international LNG club. In a Wall Street Journal interview he laid out several options to jump start Iran’s gas ambitions, including finishing the Iran LNG project, which is 40% completed.
Trovag Amundsen G.J.,Statoil |
Copin D.,Total S.A. |
Madros N.H.,Petronas |
AL Narayanamoorthy T.R.,Petronas |
And 3 more authors.
International Gas Union World Gas Conference Papers | Year: 2015
The world requires secure, reliable, and affordable energy supplies to sustain economic growth. The fossil fuels are expected to continue to play a significant role in supplying the needs of future global energy. In the meantime, carbon dioxide emissions associated with fossil fuels are thought to be the main cause of global warming. There is an increasingly urgent need to mitigate greenhouse gas emissions, including those related to energy production and consumption. Carbon Capture and Storage (CCS) is one of the most viable technologies currently available to mitigate GHG emissions from large-scale fossil fuel usage. CCS involves the capture, transport, and injection of CO2 into suitable geological formations. The injected CO2 is monitored to verify its storage. Although CCS from coal has generally received most attention, the use of CCS with gas can enhance natural gas' advantage of the low carbon emissions. This report studies the various merits and synergies of CCS on gas and examines how CCS can be applicable and advantageous to gas industries. ©TOTAL. Source