DYWIDAG LNG technology STRABAG International GmbH
Our Company DYWIDAG has been renowned in the worldwide construction business for technical excellence and comprehensive service since 1891. DYWIDAG is now part of STRABAG SE, one of Europe s leading construction groups. STRABAG s activities span the entire construction industry (Building Construction and Civil Engineering, Transportation Infrastructures, Special Foundation Engineering and Tunnelling) and cover the entire value-added chain. Building Construction & and Civil Engineering Transportation Infrastructures Special Divisions DYWIDAG has been involved in the development, design and construction of storage systems for liquefied gases with prestressed concrete components right from the beginning nearly 50 years ago. The current safety standards for container systems were to a large extent influenced by DYWIDAG s work. STRABAG constantly advances the technology to further the success of these storage facilities. Solutions like the development of isolators for LNG Tanks in areas with seismic activity are typical for our special know-how. Gases requiring storage range from natural gas and ethylene to propane and butane, which are by-products of oil refining. LNG is the abbreviation for Liquefied Natural Gas. Natural gas is liquefied by cooling it to around -162 C. This reduces its volume by a factor of about 600. The space required for transport and storage is accordingly reduced. Liquefaction is therefore an economical solution to the problem of storing large quantities of gas at atmospheric pressure and transporting them by ship over large distances is technically safe. The beginning and end of such transport chains are formed in each case by a base load terminal with storage tanks. Currently the largest above-ground tanks have a capacity of 200,000 m³. Future tanks are planned with a capacity of 250,000 m³ to 300,000 m³. A further reason for storing liquefied natural gas is to cover peaks in demand in a regional or local supply network. This takes place in a peak-shaving facility, where the tanks are, however, generally smaller than in liquefaction or receiving plants. Smaller tanks are also required for Small Scale LNG Terminals or Bunker Stations and are as well within the range of our development and project range. Cover: Tongyeong LNG Terminal (South Korea)
1 MILESTONES STRABAG/DYWIDAG LNG Technology has been involved in the development of LNG storage systems right from the beginning and built its first prestressed concrete protective tanks in the late 60s. By exchange of experience and knowledge between engineering and construction the permanent development and improvement of the engineering methods and design solutions is guaranteed. STRABAG/DYWIDAG LNG Technology offers solutions for liquefied gas storage systems which meet all protective requirements, e.g. spillage, liquid impact, explosion, missile impact, fire. STRABAG/DYWIDAG LNG Technology is actively involved in the development of isolators in order to damp seismic influence on the tank structure. Together with their international operating partners STRABAG/DYWIDAG LNG Technology offers the entire scope for the engineering, design and construction of on-shore Export and Import Terminals - starting from the FEED to Cool Down. 1 LNG Tanks, Sagunto (Spain) 2 LNG Tank, Stuttgart (Germany, 1968) 3 Regassagunto LNG, Sagunto (Spain, 2002) 4 Atlantic LNG Tank 4 (Trinidad & Tobago, 2002) 5 LNG Tanks, Inchon (South Korea, 1993) 2 4 3 5
DYWIDAG LNG Technology KNOW-HOW basic research and feasibility studies development of different solutions, comparative studies of operational safety and economy, costs and period of construction risk analysis collection of reference data on material properties, performance of structures and materials under cryogenic conditions by laboratory experiments and model tests basic and detail engineering EPC contractor not only for concrete works and full containment tanks, but also for the coordination of the steel and plant erection supervision, quality assurance and control FULL CONTAINMENT SYSTEM The outer tank in the form of a prestressed concrete containment represents the protective component in the container system. The inner tank as an independent component forms the primary storage tank. The thermal insulation between the inner and outer tanks prevents cold loss, thus limiting the vaporisation rate. The inner and outer tanks are both stable under hydrostatic load. In addition, the design of the tank system aims at restricting all the effects of any conceivable accident to the inner storage system. The outer tank protects the primary tank from potential operational disturbances from outside sources and, conversely, also protects people and the environment from a potentially explosive gas-air mixture forming as a result of a leak in the inner tank. In this system the outer tank has to fulfil the following protective functions: physical protection e.g. against pressure waves from explosions, impact caused by parts of the plant flying through the air, helicopter collision and liquid impact thermal protection e.g. against fire in adjacent tanks, fire on the tank roof, cold shock, collecting and retaining fluids or gases e.g. escaping from a leak in the inner tank. These requirements mean that the outer tank must form a self-contained prestressed concrete containment. 1 Hazard and Safety Investigations 1
1 PROTECTION FROM EARTHQUAKES Locations with high levels of seismic activity pose special problems. Large storage tanks have a fundamental frequency of approx. 2 to 10 Hz and thus lie more or less within the resonance range of typical earthquakes, i.e. they will be accelerated 3 to 4 times more than the ground on which the tanks are built. This critical condition can be largely avoided if the vibrational behaviour of the tank can be decoupled from that of the ground. One step in this direction is to isolate the base, a technique also applied to machine foundations. To effect this, the container is placed on isolators. If the isolation is correctly designed to take into account the dynamic properties of the ground and the structure, the stresses on the vulnerable steel inner tank can be reduced by 80-90 %. For these calculations a dynamic model of the tank structure is prepared. The complex interaction between foundation, isolators, outer tank, inner tank and the liquid can be reproduced realistically with a Lump-Mass model. DYWIDAG pioneered the worldwide systematic use of base isolation for large-scale LNG Tanks in the design of the Inchon LNG Receiving Terminal, using round elastomeric bearings made of natural rubber and steel. 1 Tongyeong LNG Terminal (South Korea) 2 LNG Tanks, Inchon (South Korea, 1993) 2
DYWIDAG LNG TECHNOLOGY SMALL SCALE LNG LNG is becoming more and more accepted as a fuel for ships and ferries and therefore smaller LNG Tanks had to be designed over the last years to create an infrastructure. The industry is always looking for new means of energy supply and has developed engines and fuelling stations to run vessels and trucks either on hybrid or on gas alone. The low emission values of LNG make it the ideal medium to comply even with the new environmental requirements after 2015. Together with Linde LE/Cryo AB, we have established the first small scale LNG Terminal in Sweden for AGA AB. This terminal operates as centre for the supply of Stockholm by truck and will in the near future operate as bunkerage station for the shipping industry and ferries in the Baltic sea. 1 4 LNG Tank, Nynashamn (Sweden) 1 2 3 4
1 SAFETY PHILOSOPHY Our safety philosophy has led us to develop and continually enhance the design and construction of such storage tank systems taking into account all aspects of safety. Together with the client and partners for the mechanical and electrical components, solutions fulfilling the highest safety and quality requirements can be realized. The main feature of the DYWIDAG tank-design is the principle of operability during and after an accident and of damage limitation. This is guaranteed by means of a monolithic full containment, using prestressing technology under cryogenic conditions. Extensive computations have proven that monolithic containment is capable of withstanding even the impact following a sudden rupture of the inner tank. QUALITY SYSTEM (QS) In the early 1990s DYWIDAG successfully implemented a Quality System to meet the specific requirements set forth by DIN/ISO 9001 (EN 29001). Since then the Quality Manual as well as numerous Company Procedures are operative and compulsory for all activities. This system was continually enhanced and maintained and is now fully integrated in the Quality System of the STRABAG Group. The STRABAG QS is certified by TÜV Rheinland Cert GmbH. Regular audits take place and the compliance with the approved standards is renewed on a regular basis. 2 3
DYWIDAG LNG TECHNOLOGY Safety Accident Prevention A consistent and rigid enforcement of the STRABAG safety policy, the distribution of our safety booklet, induction lectures for all site personnel at the beginning of and regular updates during the employment, together with a high standard of personal protective equipment for the workers, support STRABAG s continuous efforts to prevent accidents on construction sites. It is the policy of STRABAG to safeguard its employees and others and to pay the greatest attention to protecting the environment by selecting the proper working methods and the materials necessary. Research and Testing Special knowledge of the material behaviour at low temperatures is required in order to develop and design structures for production, storage and transportation of liquefied gases. In more than 40 years STRABAG has acquired sophisticated know-how in this field by carrying out theoretical work and special tests on reinforced and prestressed concrete and steel. Besides solving material-related problems considerable research effort has been devoted to the behaviour of offshore structures under environmental forces such as wave action, sea water pressure, ice forces etc. The results of these investigations have established an excellent composition of materials providing a maximum degree of safety against structural failure, even when the storage system is subject to extreme hazards. Research is never a stand-still: STRABAG continuously pushes its research and test activities. Newly developed materials are scrutinized regarding their adequacy for the special conditions required by the liquefied gas. Alternative ways to make the storage facilities even more efficient and economical are measured and new construction methods in the technical sector are monitored. 1 Regassagunto LNG, Sagunto (Spain) 2 Certificate ISO 9001 3 Certificate ISO 14001 4 Certificate BS OHSAS 5 6 Cryogenic testing of prestressing systems 5 4 6
OUR REFERENCES Starting with the construction of the first LNG Tank in 1968, DYWIDAG played a leading part in the planning and construction of the following tanks for liquefied gases LNG Tank Mossel Bay, South Africa Client: Mossgas, Award: 1990 Technical Data: full containment tank, with a liner system consisting of vapour barrier and PU foam on floor and wall, Capacity: 10,000 m³ LNG Tanks Lumut, Brunei Darussalam Client: Brunei LNG Sdn. Bhd., Award: 1991 Technical Data: full containment tank, Design & Build Capacity: 2 x 65,000 m³ LNG Tanks Inchon, South Korea Client: Korea Gas Corporation, Award: 1993, Technical Data: full containment tanks, deep pile foundation and pile cap, tanks with seismic isolators, Design & Engineering & Prestressing, Capacity: 10 x 100,000 m³ LPG Tanks Ruwais, Abu Dhabi, United Arab Emirates Client: Abu Dhabi National Oil Company, Award: 1995 Technical Data: full containment tank, 1 propane tank and 1 butane tank, Design & Build, Capacity: 2 x 43,000 m³ LNG Tanks Qalhat, Sultanate of Oman Client: Oman LNG LLC., Award: 1997 Technical Data: full containment tank, Design & Build Capacity: 2 x 120,000 m³ LNG Tanks Tongyeong, South Korea Client: Korea Gas Corporation, Award: Tanks 3-16: 2000 2008 Technical Data: full containment tank, Design & Engineering & Prestressing Capacity: Tank 3-12: 10 x 140,000 m³, Tank 13-16: 4 x 200,000 m³ LNG Tank 4 Point Fortin, Trinidad and Tobago Client: Atlantic LNG Company, Award: 2002 Technical Data: full containment tank, piled foundation, Design & Build Capacity: 160,000 m³ LNG Tanks Bal Haf, Yemen Client: Yemen LNG Company Ltd., Award: 2005 Technical Data: full containment tank, Design & Engineering & Prestressing, technical advisor on site, Capacity: 2 x 140,000 m³ LNG Tank Nynäshamn, Sweden Client: AGA Linde Gas, Award: 2008 Technical Data: full containment tank, Design & Engineering Capacity: 20,000 m³ LNG Tanks Sagunto, Spain Client: SAGGAS, Award: Tank 1+2: 2003, Tank 3: 2006, Tank 4: 2009 (incl. option for Tank 5), Technical Data: full containment tank, Design & Engineering & Prestressing, Capacity: 4 x 150,000 m³ LNG Tanks Pyeongtaek, South Korea Client: Korea Gas Corporation, Award: Tank 11-14: 2004, Tank 19+20: 2008, Tank 23: 2009, Technical Data: full containment tank Prestressing Capacity: Tank 11-14: 140,000 m³, Tank 19, 20, 23: 200,000 m³ LNG Tanks Queensland, Australia, Client: British Gas Queensland Curtis LNG Ltd., Award: Tank 1&2 2010, Technical Data: full containment tank Design & Engineering, Prestressing, Capacity: 2 x 140,000 m³ LNG Tanks Gladstone, Australia Client: Santos/PETRONAS, Award: 2 Tanks 2011 Technical Data: full containment tank Design & Engineering, Prestressing Capacity: 2 x 140,000 m³
STRABAG International GmbH Leopoldstrasse 250c 80807 München Tel. +49 89 360555-2310 Fax +49 89 360555-2395 info@strabag-international.com 09/2012/500