SCHADE Lagertechnik GmbH, one of the world’s leading manufacturers of equipment for bulk material stockyards and blending beds, and part of the AUMUND Group of companies, has developed the patent for a technical solution the realization of which will cause a sensation in above all the bio-fuels and coal sector. Through employment of two booms the intake and reclaim capacity can be doubled without any difficulty according to SCHADE engineers. Circular storages, which offer the simple option of a covered area and — compared with longitudinal storages — result in a 50% smaller footprint whilst offering comparable storage capacity, can be realized by SCHADE with diameters of up to 150 metres.

Subject of the patent is a circular store which, in contrast to the solutions employed hitherto, features not just one, but two raisable and lowerable scraper booms on the central column. These scraper booms are positioned symmetrically to the central column in the storage area and are interlinked in such a manner that they serve as a mutual counterbalance and thus the traditional counterbalance can be dispensed with. The stacker boom can be stored in the conventional design mode on the central column, centrically and slewable or, in the form of a symmetrical design, cast off the material to the opposite sides. Also in this latter case, as with the scraper booms, a counterbalance is not required.

With the invention comes the advantage that, on simultaneous employment of both booms, an almost double intake or reclaim capacity is achieved compared with conventional circular storages.

“Reclaim capacities of 5,000tph [tonnes per hour] to 6,000tph are no problem with this device under suitable conditions,” reports SCHADE managing director Karl-Heinz Fiegenbaum. Particularly in the case of high performance and high capacities the new machine could present an alternative to solutions employed thus far, especially in the fields of bio-fuels, mining, power and ports and terminals.

Thanks to the high capacities achievable during simultaneous filling and discharging, the system can be employed for not just pure storage but also for transshipment as an interim buffer, thus enabling short residence times for loading and unloading of ships and railway wagons. The system accommodates ever higher demands according to availability and functions via employment of the two booms on a redundancy basis, i.e. if an operational stoppage occurs in one of the booms the unit opposite continues working. Similarly, the total weight of the machine is reduced as a result of the counterbalance being replaced by the additional stacker or scraper boom — as are foundation expenditure and space requirement for each tonne of bulk material moved. Depending on the dimensions of the circular storage, on complete filling, 50,000m3 (starting at a diameter of 90m) up to 450,000m3 material (at diameters of 150m) can be stored. 
With the realization of the market-ready patent solution which is now being offered proactively in the marketplace, SCHADE once again demonstrates its flair for innovative solutions: already in 1959 the company presented the world’s first scraper reclaimer with double boom, eight years later SCHADE installed the first scraper reclaimer for a coal-fired power station. Amongst the more than 600 references worldwide, nine of the world’s largest circular storages are to be found (Mai Liao,Taiwan) and one of the world’s largest portal scrapers for coal (Dawson, Australia).