The design and construction of a grain processing plant require a high degree of technical expertise and careful planning to ensure that the plant is as efficient and effective as possible. By working with experienced engineers and mill construction experts, CESCO can help to optimize the processing plant throughput and minimize their operating costs.
Dr. Martino Celeghini
CEO of CESCO EPC GmbH
Building an efficient grain processing plant requires careful consideration of several factors to ensure the highest quality processing. From the selection of equipment to the layout of the facility, every aspect of the construction process needs to be carefully planned and executed.
One crucial factor to consider is the selection of the right equipment for the plant. Equipment like grinders, sifters, and silos should be chosen based on their intended use, the volume of grains they will handle, and other project-specific requirements. CESCO affiliate company MMW, with more than 130 years of experience in mill equipment and related areas, can develop complete line concepts from intake to storage, milling, and packaging of final products for whole plants or plant segments, whether they’re new green-field investments or modification, refurbishment, and extension of existing plants.
The first step in design is clarifying the customer’s request in terms of flour characteristics and the focus on processes after the milling operation. For deep processing applications like the extraction of starch, gluten, or proteins, the flour specification is the most important input data that needs to be clarified at the project’s start. The flour specification contains values like humidity, ash content, coarse fibers, oil content, and the maximum loss of husks during milling. Granulometry is also essential and usually defined by a certain percentage of particles with a maximum diameter dimension in micron (e.g., 98% below 250 µm and 35% below 50 µm). Also the quality of the grain needs to be defined with regards to the grain humidity and percentage/composition of the impurity.
3D-FE model of a mill building, allowing for structural optimization and reducing weight, cost, and loads on the foundation.
The flow diagram in the silo and mill plant needs to be drafted, specifying the product flow through each piece of equipment and the possibilities of controlling it. This includes flow diagrams for silo storage, including intake, pre-cleaning, drying, conveying, storage, and outloading/packaging components. For the mill section, there should be separate flow diagrams for cleaning, milling, waste and flour silo sections, providing the quantitative mass balance to dimension the daily storage and waste bins, as well as the number and capacity of each machine. The battery limits need to be clarified in case of multiple partners involved in the processes, which are the input and output positions in the complete flow diagram for the main product, by-products (husk, waste), and the required energy sources (electrical, compressed air, water, water moist). These limits must be defined in terms of their code number, position, quantitative parameter (mass flow, volume flow, electrical power, etc.), and qualitative requirements (referring mainly to international standards). The filtering solution must be described in detail, highlighting the position of the filtering equipment and the emission points, which describe the position, quantitative (mass flow, temperature), and qualitative (composition) parameters of the emissions generated by the plant.
The energy balance analysis describes the energy consumption for all installed equipment in terms of maximum power installed and maximum simultaneous power required for each section (silo storage, cleaning, milling, waste, and flour sections). This allows the investor to specify the power requirements for plant operation. A basic concept for the control system showing the central and local control and appliances in the management, control, and process planes is also required, together with a list of laboratory equipment needed for operation.
Oat mill building in Sweden with round and square silos and conveying equipment.
Another important aspect is the design of the milling plant itself. This includes everything from the facility’s layout to the materials used in its construction. The plant’s design must be carefully tailored to the specific needs of the project, taking into account factors like the type of grains being processed, the required throughput, and the overall processing goals.
The design process involves developing a complete 3D layout of the storage and milling plant, starting from simple sketches, passing through 2D overview drawings and master plans, arriving at a full 3D CAD model integrating into one single model all the single designs of silos, catwalks, conveyors, milling equipment, and all other equipment. This 3D model allows the identification of collisions and allows the finalization of the interfaces between the different components, allowing the erection team on-site to easily understand the final outcome of the project. Out of the 3D model, then single 2D drawings for each level of the mill building can be obtained.
Silos, conveyors, and milling equipment are essential components for any storage and processing plant; however, they alone are not sufficient for the smooth operation of a plant. Various accessories and steel structures are required to ensure its functionality and safe operation. CESCO offers a range of steel structures for process dedicated buildings and industrial plants, including bridges, walkways, entablatures, solid frames, machinery towers, and sheds. These custom-made steel structures are designed to support process machines or sections, stairs, roofing, and cladding, and can be tailored to specific contract requirements. Our team of experts uses advanced 3D FE software to perform complete internal architectural and functional design and static calculation of all steel structures within a plant following the static and dynamic loads definition and the methods according to Eurocode standards. This approach ensures that all structures are optimized for maximum efficiency and structural integrity. This reduces the weight of the structure itself, therefore its costs, but also the loads on the foundation and therefore the foundation costs themselves. The results of the static calculations allow for the definition of the loads and basic dimensions of the foundation for the silos, intake-pit, weighbridges, machinery towers, and mill building. These are then passed to the civil engineering company which will assess these requirements together with the results from the soil investigation.
Flour mill building, machinery house building and steel support structures in Turkmenistan.
The soil type and loading capacity directly affect the cost of the foundation and the investment accordingly. The improvement of loading capacity can be reached by significant excavation, soil removal or substitute or filling with selected material, or using pile instead of slab foundation. In addition, the deep-water level can limit the possibility of tunnel or ventilation channel, which are efficient measures to reduce the elevation of the plant. These aspects are usually underevaluated by the investors but can be significant and need to be considered by professional soil investigations before the commercial evaluation of the whole plant investment.
When it comes to selecting equipment for a grain processing plant, there are several key factors to consider. One of the most important is the efficiency of the equipment itself, which can have a significant impact on the overall productivity of the plant. This includes everything from the power consumption of the equipment to the ease with which it can be maintained and repaired. Once the choice is completed, a final list of all equipment is listed, showing the quantity, the outer dimensions, the weight, and the power consumption, allowing the investor to release them for purchase and installation.
In addition to equipment selection, there are several other factors that must be considered in the construction of an efficient milling plant. These include everything from the layout of the facility to the choice of materials used in its construction. Also safety measures must be integrated into the design of the plant to ensure the safety of personnel, equipment, and the environment. This includes everything from fire safety systems to dust control systems, which are critical in preventing explosions and maintaining a safe working environment.
In addition to the construction and design of the plant itself, it is also important to consider the maintenance and upkeep of the equipment and facility. Regular maintenance and cleaning are crucial to ensure that the equipment remains in good working order and that the plant continues to operate at peak efficiency. This includes routine inspections, cleaning of equipment, and replacement of worn or damaged components. By implementing a comprehensive maintenance plan from the outset of the project, plant owners can minimize downtime, reduce repair costs, and extend the lifespan of their equipment.
In conclusion, the design and construction of a grain processing plant require a high degree of technical expertise and careful planning to ensure that the plant is as efficient and effective as possible. By working with experienced engineers and mill construction experts, CESCO can help to optimize the processing plant throughput and minimize their operating costs.
Milling plant in Russia with all components from intake of raw material, storage, conveying to the mill up to flour transportation to the wet process.