Overview
Traditional handling of bulk cereals in Port Areas can lead to large amounts of suspended dust particles being released into the air. As a result, substantial air pollution is created which can cause allergic respiratory illnesses amongst local people. In recent years, La Coruna Port has expanded its handling of these cereals, reflecting their increasing importance to the Galician agriculture and stock-rearing industry. This has also involved an expansion in the range of cereals handled, from 3 traditional products to 22. Some of these cereals, such as transgenic soya, bring with them an increasing risk of pollution. Although the dust emissions do not currently infringe the current National and EU Environment Legislation they present an increasing irritant for the local population. The extent of public awareness of these problems can be seen in the commitment made by the Port Authority itself and the Regional Government to co-finance a project to reduce these dust emissions. The successful development of such a system would substantially reduce the environmental impact in the Port Area. It could also be adapted to other areas, like port infrastructures, industries and railway stations where there exists a similar environmental pollution problem.
The main aim of the project was to reduce air pollution caused by grain dust emissions in Port Areas, consequently reducing the amount of health problems caused of an allergic character. The project contemplated a 90% reduction in these emissions by the end of the period. This would be achieved through the development of a system with two key characteristics. (A specialist engineering company Buhler SA would take responsibility for the design and implementation of the system) Firstly, the bulk cereal handling activities would be isolated from the open air, so as to prevent the escape of dust into the atmosphere. Secondly, an integrated handling and management computerised application would be developed to facilitate the monitoring and control of the dust emissions, amongst other operational activities. The system would commence once the bulk cereals had been emptied out of the ship with a power shovel. The cereals would then be sucked up by a hopper and transferred onto conveyor belts that would be hermetically sealed. These would transport the material in a closed circuit before being weighed, stored and loaded onto lorries.
Funding
Results
The project required a six month extension to complete its objectives due to a variety of reasons: financial problems related to the size of the investment required, delays arising from the acquisition of building authorizations from the Port Authority, and changes in the design. However, the completion of the project meant an important step towards reducing the environmental impact of dust pollution and enhancing public health in the area. The project introduced two innovative elements in the system: the type of hopper and the capacity of the computerized control system. The hopper was powerful enough to be able to suck up all the grain and dust produced from the boat, whilst at the same time being extremely mobile, lending itself to use throughout the Port area. This hopper was also provided with, in its external upper part, dust detector shutters, filters, electric ventilators, chains, conveyors and telescopic tubes for unloading the cereals onto the conveyor belts. These belts, hermetically sealed, covered the entire distance to the tower where the goods were weighed and controlled. This weighing tower was the second innovative element, controlled by computers, it contained an electronic automatic weighing machine, electronic ventilators and filters. From the tower the orders were given to carry out the storage as well as the loading of the cereals on to the lorries. From the same centre, the level of dust emissions could also be monitored. The project was developed in three phases: starting with the installation of the mobile hopper with 6 filters for vacuuming up the dust, followed by the mechanization of the transport, warehousing and loading facilities. The final phase replaced the original activity of a loading system: warehouse to boat, by the introduction of a second mobile hopper in the initial stage. This had the objective of increasing the capacity and speed of transferring the grain from the boat and reducing the overall project costs.
The project claimed a 90% reduction of dust emissions from the grain handling process, which should contribute to a decline in related allergic respiratory illnesses. The system also proved its viability, facilitating an optimization of the operational system of bulk cereals handling. This led to an improvement of the handling capacity to 500.000 TM/year, together with the reduction of loss of merchandise through handling difficulties. Overall, the project offered a well-designed system that had potential to be transferred to Port or other facilities responsible for transporting grains in bulk.