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Henderson, Andrew R. (Section Wind Energy, Delft University of Technology) | Morgan, Colin (Garrad Hassan & Partners Ltd) | Barthelmie, Rebecca (Risø National Laboratory) | Smith, Bernie (John Brown Hydrocarbons Ltd) | Sørensen, Hans C. (Energi & Miljoe Undersoegelser (EMU)) | Boesmans, Bart (Tractebel Energy Engineering)
ABSTRACT After several decades of theoretical developments, desk studies, experimental wind turbines and prototype windfarms, the first largescale commercial developments of offshore windfarms are now being built. To support and accelerate this development, the European Commission funded a project, ‘Concerted Action on Offshore Wind Energy in Europe’ (CA-OWEE), which aimed to gather, evaluate, synthesize and distribute knowledge on all aspects of offshore wind energy, including: offshore technology, electrical integration, economics, environmental impacts and political aspects. The partners are from a wide range of fields and include developers, utilities, consultants, research institutes and universities. This paper reports on the final conclusions of this project. INTRODUCTION Offshore wind farms promise to become an important source of energy in the near future: it is expected that within 10 years, wind parks with a total capacity of thousands of megawatts will be installed in European seas. This will be equivalent to several large traditional coalfired power stations. Plans are currently advancing for such wind parks in Swedish, Danish, German, Dutch, Belgian, British and Irish waters and first such park is currently being constructed at Horns Rev, off Denmark's western coast. Onshore wind energy has grown enormously over the last decade to the point where it generates more than 10% of all electricity in certain regions (such as Denmark, Schleswig-Holstein in Germany and Gotland in Sweden). However, this expansion has not been without problems and the resistance to windfarm developments experienced in Britain since the mid 1990s, is now present in other countries to a lesser or greater extent. However the cost of wind turbines is falling and is expected to continue doing so over the coming decade and once sufficient experience has been gained in building offshore projects, the offshore construction industry is likely to find similar cost-savings.
Heerten, Georg (Naue Fasertechnik GmbH & Co. KG) | Jackson, Angus (International Coastal Management) | Restall, Simon (Soil Filters Australia Pty Ltd) | Stelljes, Katja (BBG Bauberatung Geokunststoffe GmbH & Co. KG)
ABSTRACT: Continuing coastal erosion across the world is leading to the development and installation of innovative techniques for the effective and unobtrusive shoreline and near shore control. This paper looks at a variety of coastal structures built utilising only sand filled goesynthetics over the last fifteen years. INTRODUCTION The use of sand filled geotextile units as permanent construction elements in coastal works as a replacement of rock or concrete armour units elements is already more than 50 years old. With the increasing cost of the "conventional" construction materials and environmental awareness of coastal engineering activities, the use of sand filled geocontainers and tubes especially made of nonwoven staple fibre geotextiles has increased. Sand filled geocontainers and tubes forming "Soft Rock Structures" have proven to have significant environmental advantages over conventional "hard" rock, so that they have also been used in areas where rock is readily available at a reasonable cost. CASE STUDIES Groyne – North Kirra, Gold Coast, Australia This project pioneered the use of multiple, large diameter tubes in Australia. The structure was designed as a temporary structure for a design life of 5 years as an erosion protection groyne. Despite some initial damage by vandalism, this structure is now over fifteen years old and has been covered by sand nourishment. As a result, a number of other structures in a variety of configurations were constructed in the Gold Coast and other areas. Groyne – Maroochy River, Sunshine Coast, Australia In 1994, two major groynes were constructed in the Maroochy River on the Sunshine Coast following extensive model testing and studies by the Coastal Management Branch of the Department of Primay Industries. The Maroochy Shire Council constructed these groynes to protect the badly eroding northern shore of the popular Cotton Tree recreational holiday caravan park.
ABSTRACT Flue gas desulfurization scrubbers for waste incineration plants can be lined with soft rubber or hard rubber for corrosion protection. Hard rubber is cured under high temperature and pressure in an autoclave. The advantage of hard rubber is the excellent temperature and chemical resistance. We have experience with hard rubber lined scrubbers that are in service without failures for over 20 years. FIELD HISTORY Flue gas desulphurization (FGD) scrubbers for waste incinerator plants have been in service now for many years. Figure 1shows common materials used for corrosion protection of scrubbers These are stainless steel, fiber reinforced plastics (FRP) and rubber lining over carbon steel. Recently we have seen stainless steel scrubbers being rubber lined due to waste stream changes. There are several ways how to use the benefits of rubber lining over other materials. The chemical composition and the temperature range of the flue gas can show major variations during operation depending ultimately on the nature of the waste which is burned. Its typical conditions at the scrubber inlet are shown in figure 2. Past experience shows that, over a period of many years, the waste composition has changed dramatically because of change of consumer behavior, local and federal regulations and general changes in the waste stream. Therefore the corrosion protection system for flue gas scrubbers for waste incinerator plants needs to cover a wide variety of operating conditions. Experience of more than 20 years of operation of hard rubber lined scrubbers shows the excellent performance of rubber in those areas. through out waste composition changes. The first hard-rubber lined scrubber was installed at a waste incineration plant in Kiel, Germany in 1974and is still in operation without problems. Subsequently hard rubber linings have been installed in over 75 scrubbers, all of which are still in operation.
1.0 Introduction With the expansion of offshore operations in the deep and shallow water regions of the world's oceans a need for more accurate engineering design of offshore equipment has become apparent. The associated design criteria include considerations of ocean wind wave effects. Yet methods of accounting for these effects are still in widespread use. The dichotomy between the presently used wave design methods and the need for innovative, cost effective engineering methods may have unwanted and unnecessary monetary consequences for the offshore industries. This paper is offered with the hope that it will help bridge the gap between recent advances in wave research and the needs of the offshore industry. This "gap" is perhaps best thought of as an "Applications gap." The following Section describes the recently concluded Joint North Sea Wave Project (JONSWAP); a large multi-nation experimental effort designed to understand the processes of wind wave generation and dissipation. Section 3 describes selected experimental results and their implications to the offshore industry. The final Section offers suggestions for closing the applications gap. 2.0 Background Previous reports (Barnett, 1970a, 1970b) have described the history, goals, and procedure of JONSWAP. This Section presents only a brief review of these discussions. An international group of scientists met in Bern, Switzerland in 1967 to discuss the unsatisfactory nature of then existing measurements on wind wave generation and dissipation. The result of the meeting was a proposal to measure wave generation and dissipation processes during a large scale experiment in the North Sea. Funding from the governments of England, Germany Holland, and the United States, plus NATO made it possible to carry out the experiment during the summers of 1968 and 1969. The experimental site was located off the Island of Sylt (Fig 1), an infamous nudist resort on the border of Germany and Denmark. A total of thirteen measurement stations were located out from Sylt (Fig 1). Under conditions of offshore (east) wind, the measurement array afforded excellent data on limited fetch wave spectra (generation). During light (onshore) winds the measurement of swells propagating from the outermost station in toward the coast of Sylt provided data on wave dissipation. Numerous wind, wave, and current measurements were made throughout the experiment. Sufficient-to-say, the statistical and directional properties of these three geophysical fields were simultaneously monitored on a nearly continuous basis for a total of two months. Analysis of the 50 million data points gathered during the experiment was a slow tedious procedure. At that time the experienceand facilities for handling and analyzing such large amounts of data did not generally exist among the European participants. It was, therefore, necessary to develop these capabilities. The final scientific analyses of the data were completed by an international scientific team at Woods Hole during the spring and summer of 1971.
Hecht, F. (DEA, Deutsche Erdöl-Aktiengesellschaft, Hamburg) | Helms, H. V. (PRAKLA, Gesellschaft für praktische Lagerstättenforschung, Hannover) | Kehrer, W. (WIAG, Wintershall-Aktiengesellschaft, Celle)
SY~Ol'SlS. Detailed reflection-seismic surveys have been carried out all over Schleswig-Holstein. They have resulted in an accurate delaneation of geological structures, because the exact stratigraphical position of typacal seismic horizons was obtained from well data, and becausp on a regional scale, certain horizons could be traced by means of uniform velocity-parameters. The geophysical investigation was considerably intensified when exploration wells found excellent oil reservoirs in the Wealden and Dogger. Thus, the geophysical problems changed from those associated with salt-domes to those arising in the search for structural and stratigraphical traps within the Dogger (Chapter P. The geophysical results, combined with those of more than 40 deep wells, have furnished detazled stratigraphical, lithological and structural data on the most dominant structures, the flanks of salt domes and sedimentary basins. As a result, the main structural units of Schleswig-Holstein have been disclosed as:the West-Schleswzq block, the East-Holstein block both being smooth uplifts with structurally high-lying Trias, and the Middle-Holstein block, which is divided into the two deep-rooted Jurassic troughs of Heide and Bramstedt-Kiel with marked subsidence and sedimentation during the Jurassic, and the Rendsburg uplift which lies between them and is characterized by high-lying Trias and by shallow depressions between salt-diapirs which have a Rhenish trend (Chapter II). The paleogeographical and structural genesis of these Jurassic troughs is discussed in detail (Chapter III). Typical Saxonian tension tectonics are confined to the Middle-Holstein block, the western and eastern boundaries being characterized by strong fault zones. A distinctive swing from S-N to SE-NW in the northeastern part of the Middle-Holstein block probably indicates a break in Stille's U Mittelmeer-Mjosen-Zone », caused by proximity to the (1 Tempelburger Achse ». The Rhenish zone reappears again farther north in the Zechstein sali dome basin of Northwest Jutland (Chapter IV). The newly discovered oil fields of Schleswig-Holstein produce exclusively from the "Wealden" (Hohenworden) and the Dogger (Hohenworden, Plon, Boostedt, Bramstedt). They are confined, together with the long known deposits on the Heide salt-diapir, to the Jurassic troughs and the Tertiary depression zones. The conclusion is justified, that the development of the oil deposits depends on the structural configuration of the area. The Lias with its sapropelific Sediments is believed to be the source rock, from which the oil was moved as a result of the enormous subsidence in the Tertiary depressions (Chapter V). Rl%WMIk Dans le passé, tout le Schleswi