Autonomous disposal of ordnance at sea
engineering. tomorrow. together. At thyssenkrupp Marine Systems this is more than just a claim. Every day our engineers develop innovations and naval technologies of tomorrow. A recent example: A pilot plant for clearing explosive ordnance from the North and Baltic Seas.
The seabed of the North and Baltic Seas is littered with legacies from two world wars: According to estimates, about 1.6 million tons of chemical and conventional ordnance lie in German marine areas alone. The metal shells of bombs, torpedoes, mines, and grenades are eaten away by rust after more than 70 years of dumping on the seabed.
A situation, that is increasingly dangerous as the old ordnance is leaking carcinogenic chemical substances from the explosives into the seawater, which is then absorbed by fish and shellfish. Thus, the ordnance not only endangers underwater work through possible explosion, but also poses a continuing danger to humans, the environment and the ecosystem as a whole.
A safe solution on an industrial scale
"Until now, the clearance of the explosive ordnance was only done manually by the explosive ordnance clearance service. In some cases, the ordnance have been brought to a controlled detonation which caused additional pollution," explains Jan Krabbenhöft, Head of Service at thyssenkrupp Marine Systems. "But this kind of clearance caused many hazards not just for the environment but also for the crew. Furthermore, compared to the amount of dumped ordnances (1.6 Mio. Tons) it was by far too slow to describe a possible solution for the problem. So far, only minimal amounts of the existing ordnance in our seas have been cleared."
However, time is pressing. The severe corrosion on the seabed could soon make salvage impossible for good. That’s why our engineers aimed to use the remaining time efficiently. „In a shared effort experts from thyssenkrupp Marine Systems and ATLAS ELEKTRONIK have taken on the task and developed a solution based on existing expertise“, says Krabbenhöft. With their new approach commercial clearance on an industrial scale is tangible.
Remote operation saves lifes and the environment
The result: An mainly autonomous working pilot plant. „As a basis, we have analyzed and further developed own technologies and used available solutions of the market“, recounts Krabbenhöft, „resulting in a new technique for the disposal of large quantities of explosive ordnance on an industrial scale.“ The industrial concept covers the entire process chain from detection to recovery and disposal and is designed for large-scale contaminated marine areas.
For the design of the pilot plant, the dumping areas of the German marine regions were specifically analyzed and taken into account. „In order to keep the risk to humans as low as possible during operation of the plant, we relied on modern robot-assisted and remote-controlled process handling, which were technologically developed within the thyssenkrupp group“, explains Jan Krabbenhöft.
Shared expertise for disposal at sea
As a landing of recovered ordnance from the sea for disposal on land is legally and logistically difficult and not reasonable for the safety of the population, the team of experts decided, an autonomous salvage at sea was the way to go. „After evaluating historical and current information on the known dumping areas, the vast majority consists of transportable ordnance that can be depolluted according to the latest environmental standards directly at sea“, explains Krabbenhöft. „Our platform was developed specifically for this purpose.“
thyssenkrupp Marine System has decades of experience in the construction of complex seagoing units and unmanned systems that are designed for worldwide military use and thus also with the handling, storage and transport of ammunition. Additionally, the interdisciplinary team of experts working on the pilot plant combines all the necessary technical skills and expertise. „As a system integrator with ATLAS ELEKTRONIK, the world market leader for sea mine defense systems, we have the technical capabilities and the stamina to implement a pilot project in the field of environmental technologies additional to our usual portfolio“, says Jan Krabbenhöft.
Technical maturity on the market
Furthermore, thyssenkrupp Marine Systems relies on the expertise of its partners and existing technical maturity on the market. With so-called “multitools”, ordnance is safely flushed out and efficiently salvaged with dredgers in coastal or flat areas. „The market provides a large number of remote-controlled industrial robots (ROVs), which can be operated from on shore with the appropriate special equipment“, explains the Head of Service.
Ordnance combustion systems are commercially available for land applications but their capacity are not suitable for large ordnance. From this followed the need to break up explosive ordnance into harmless components as a preparatory measure. „For this purpose, remote-controlled guidance systems with multi-axis robotic arms, as well as modern sawing technology or water jet cutting systems are used in our pilot plant“, explains Krabbenhöft.
Approval and start-up
The described salvage and disposal at sea has not yet been carried out on this industrial scale. For an approval direct and early coordination with the relevant responsible authorities is necessary. Initial talks with the Ministry for Energy Transition, Agriculture, Environment, Nature and Digitization of the State of Schleswig-Holstein were very encouraging. „We were promised the necessary support on the way to approval“, says Jan Krabbenhöft.
For the realization of the pilot plant up to the start of regular operation, thyssenkrupp Marine System requires a preparation period of around two years. The prerequisites for this are the budgeting of funds, the commissioning of the project in accordance with suitable procedures, and approval for operation. Krabbenhöft is certain – thyssenkrupp Marine Systems is ready: „The project is technically feasible! So in view of the necessary preparations, we want to give a clear 'full-ahead' now. “