CASE STUDY 2
Mixing plants for the New Doha International Airport
German Plant Experience LLC in Dubai has established itself within a very short space of time as one of the most important mixing plant suppliers in the Middle East. Countless building sites and large projects are supplied with ready-mix concrete produced according to international standards on GPE concrete batching plants, including one of the largest construction projects in the Middle East, the New Doha International Airport (NDIA).
GPE has supplied and installed two mixing plants for this project
Each with a capacity of 150 cbm/hr. The highest demands were and are placed on the plants. To satisfy those demands, GPE has integrated the latest plant and control technology.
Each plant consists of 6 aggregate boxes with a total storage volume of 240 cbm. In order to guarantee rapid aggregate dosing, two independent weighing belts are each dosed by 3 boxes. Hence two
aggregates can always be dosed simultaneously. The two weighing belts discharge centrally onto an elevating conveyor with a cleated belt and a belt width of 1200 mm. The elevating conveyor discharges into a preliminary silo with a volume of 6750 liters. An IME twin-shaft compulsory mixer with a concrete output of 4.5 cbm per batch is used. A 9 cbm ready-mix truck can hence be filled with two mixing batches.
In order to offer the operator optimum possibilities, each mixer is equipped with a special camera. Hence at the push of a button he can check the consistency of the concrete during mixing via a colour monitor.
Besides that, dry loading is also possible, i.e. all raw materials can be fed directly to the ready-mix truck, bypassing the mixer. In order to always have a sufficiently large reserve of cement even during periods of peak activity, each plant is equipped with a total of 9 cement silos. Four of these are
700 tonne silos that serve as a passive store from which the active silos can be filled as required.
There are four 300 tonne silos directly at the plant for cement and GGBS, as well as a 100 tonne silo for micro silica. Besides the 2000 kg cement scales, the micro silica also has its own set of scales.
In order to fulfill the stringent emission requirements, a separate filter system is installed in the plants that ensures virtually dust-free production.
WEBCon controller for highest demands
In order to meet the demands placed on the plant software by the client, the GPE control software WEBCon is used. This has made an outstanding name for itself not just in the construction of the Burj Dubai. More and more plants are presently being converted to WEBCon.
The latest web technology in conjunction with standard software components guarantees the user the highest degree of flexibility and operator-friendliness. Clear menus and self-explanatory buttons provide the operator with maximum operating convenience and a very good overview.
Two TFT monitors are connected to the master computer. The operator can hence effortlessly select recipes, input orders or set plant parameters, whilst the second monitor provides him with a visualization of the complete production process.
The plant visualization consists of an overview page, from where the operator can zoom in per mouse click on the individual parts of the plant and get detailed information. The delivery note printout was specially adapted to the customer’s requirements. Comprehensive statistics allow the customer to view consumption, fill levels and other production parameters quickly and easily. All statistics can be output at freely select able time intervals. Consumption statistics with administration of material withdrawals and nominal/actual comparisons with difference calculation are included, as are customer, building site or vehicle statistics and order statistics with the output of all components contained in the recipe.
In order to provide the user with the greatest possible transparency and operating convenience, WEBCon has been integrated in a company Intranet. The use of software standards allows the customer to install this architecture himself with little expenditure of time and costs.
Hence all employees have the possibility to view the data and production processes that are relevant to them direct from their workplace using Internet Explorer.
Once again GPE is contributing to the realization of a large project in the Middle East with this convincing plant concept.