Product outline. Titel. BBC-big bubble curtain. Revision: 12/10/2018

Transcription

1 Product outline Titel Revision: 12/10/2018

2 Contents 1. Scope 2 2. Concept 3 3. The Jäger Mare Solutions BBC - Big Bubble Curtain - single or multiple laying principle 4 Since 1942 application-oriented advisory service, material-oriented construction and system related development are the key for the Jäger Group s success. Our competence and efficiency continuously raised according to the customers demands. Our success is based on continuous product innovation, advice independent from the material as well as a friendly, competent service and zero-defect philosophy. The family business in its third generation operates world wide and is a qualified partner in the field of waste water treatment and agricultural industry as well as in machine and plant engineering and onshore wind energy. More than 900 employees working in 25 sites in Europe, the USA, Canada and China. Our vast experience in products and solutions for onshore wind applications is expanded to offshore activities. The offshore activities, grouped under the label Jäger Mare Solutions, cover noise mitigation, long term corrosion protection and scour protection. The respective system solutions are being patented in in order to secure themselves corresponding market shares to refinance the development costs. 1. Scope In the German economic zone the Bundesamt für Seeschifffahrt und Hydrographie (BSH) is responsible for offical release of wind farms. In principle, the impacts on the environment caused by the noise emissions which are generated during the construction have to be examined and presented in an approval procedure for offshore wind turbines. The ancillary clause 14 of the approvals of the BSH foresees regular measures to record and minimize the underwater noise. Thus, measurements of the underwater noise have to be performed and documented during the noise-intensive works. The efficiency of damage-protective and noise-minimizing measures have to be checked during their performance by measurements. The measurements have to be documented and the results to be reported to the approving authority. Measurements are performed and documented in all project phases. A project is divided into the following phases: Baseline survey prior to the start of construction Construction phase Operation phase Decommissioning phase Currently Jäger Mare Solutions is working on an effective method to reduce the noise during the offshore pile driving. Our engineers are focussed on reliable reduction of sound emissions during offshore pile driving below 160 db (SEL) and 190 db (peak) in about 750m distance from the emission source. The noise propagation in case of offshore impulse drivings occurs in three ways: The generated structure-borne noise is transmitted to the water column, to the air and to the ground. The noise transmission by air is neglected; a great part of the noise emissions is transmitted through the ground to the water column, but still today it is not possible to damp those noise emissions effectively and economically. Systems used in practice minimize the direct noise transmission on the water column. 2

3 2. Concept The basis is, to position the Big Bubble Curtain optimally around the expected noise source (blasting of ammunition and/or ramming of piles) und to hold it at this point in order to achieve the highest possible noise protection. The noise reduction is achieved by air bubbles escaping from the hose system, which are again generated by respective compressors. Moreover, due to various layer variants the curtain will not impair the logistic process of the jack-up vessel. The length of the hose/hoses can be individually adapted to each project. Supply vessel with hose reel and compressed air technology Bubble curtain Noise source Supply vessel with hose reel and compressed air technology Noise source Bubble curtain Bubble curtain 3

4 3. The Jäger Mare Solutions BBC - Big Bubble Curtain - single or multiple laying principle The Jäger Mare solutions BBC hose can be characterized as follows: Polyester fabric reinforced rubber hose, Operation pressure 15 bar Burst pressure 40 bar Robust outer rubber material, High wear resistance, nevertheless light and flexible Inner diameter 75mm and/or 100mm, Wall thickness 3mm. Versatile chemical resistance Seawater resistant Rot-proof, resistant to cold Cold resistant down to -35 C Heat resistant up to +100 C Resistant to ageing, UV and ozone Easy to clean and maintenance-free No clogging of the membrane by corrosion residues The hose is continuously perforated lengthwise with up to 20 slits per cm2. If air pressure is applied to the elastic hose the slits release fine air bubbles into the surrounding water. The resulting bubble curtain is even and dense over the entire length of the hose. As soon the air supply is turned off the slits are sealed due to the elastic properties of the rubber. The hose itself is compressed / folded flat by the hydrostatic pressure, so leakage of water and sand into the hose is minimized. Any sedimentation on the outer surface of the hose will be flushed away by the slight expansion after turning on the air supply and the upstream of the water / bubble mix. The perforation is designed to ensure a uniform bubble pattern along the entire length of the hose. The dimension of the perforation slits of the can be adjusted to adapt the inner friction of the compressed air over the length of the hose. To that, the volume flow, the slot geometry (length and distance of the slots) and the opening pressure of the perforation can be adapted. Various bubble sizes can also be generated to reduce different noise frequencies. 4

5 The entire length of the bubble curtain hose can be obtained by coupling several segments. A lengthwise tension applies no or only little load on the air hoses being connected by couplings, when they are rolled in or out. The tensile load is transferred by the chain. The overall design of hose can be characterized: To be laid out without air pressure Remains on the seabed during the operation Can be produced in any length desired Is connected with hose couplings according to existing requirements 5

6 Titel Contact: Franz Tekbas Key Account Manager Offshore Jäger Gummi und Kunststoff GmbH Bissendorfer Str Hannover Germany info@jaeger-gk.de Disclaimer We exclude any liability for the information and product presentations provided. Contents of technical character are based on the date of publication. Existing copyrights and rights to the use of names remain unaffected Product documentation (englisch)