Intelligent alchemy -- Asia Cement Corporation turns stone into gold

        As early as more than 40000 years ago, human beings already knew how to excavate minerals and use them in daily life. However, due to the different quality of mineral raw materials and the rising awareness of environmental protection, large-scale mining not only violates the spirit of sustainability, but also damages the corporate image. This issue will introduce how Asia Cement Corporation creates a new intelligent production mode under many restrictions.

        Xinchengshan mine, which is close to Hualien plant of Asia Cement Corporation, is in serious shortage of high calcium limestone (CAO) for cement production due to the large amount of limestone interlayer and limited mining area, as well as the large amount of siliceous, aluminous and magnesian limestone exposed in recent years. Moreover, Hualien County government amended the local ore tax in the Republic of China in 105, and Hualien plant had to pay a high tax for every ton of limestone mined, which not only increased the production cost, but also affected the overall profit.

                In the face of environmental and financial pressure, the project team of Hualien plant strives to find a breakthrough in the production process, hoping to overcome the disadvantages of natural mines, ensure the quality of limestone production and create higher profits through intelligent production mode.

        Homogenization measure 1: innovate mining layout

        As the saying goes, "know yourself and the enemy, and win every battle.". The primary task of the project team is to complete the comprehensive drilling operation of the mine, so as to grasp the overall ore bed trend and understand the content and distribution of various quality ores. According to the drilling results, the distribution of limestone composition in the mine is extremely uneven, and high calcium limestone (CAO) is lacking.

                In order to continuously provide limestone raw materials that meet the production quality, the project team established the mine resource distribution information in an intelligent mode, closely linked the personnel, machinery and mine resources, and adopted a special mining mode, which not only effectively mastered the mining quality of limestone, but also improved the variation of the maximum and minimum calcium oxide content of limestone from 40% to only 10%. Among them, the low-grade limestone without high calcium is directly supplied to the plant as the by-material for production through intelligent scheduling, which greatly reduces the outsourcing cost of by-material.

        Homogenization measure 2: real time analysis and quality control

        In addition to adjusting the mining method, the project team actively imported from France the first set of "neutron on-line analyzer" specially for limestone analysis in China's cement industry, which can provide analysis data every two minutes. Compared with the manual sampling and analysis in the past, it takes 60 minutes, and the timeliness is improved by 30 times. After testing and improvement by engineers, the accuracy also has a good performance. In addition, all the analysis data are presented through the integrated information platform, so that the mining unit and the quality control unit can get the information immediately, and carry out the limestone quality scheduling and control immediately.

                In addition, the team also developed the "intelligent quality monitoring system for limestone cutting" with the original equipment technicians, which can flexibly set the quality objectives and control conditions of limestone. When the composition deviates, it will automatically alarm, and predict and respond to the subsequent quality adjustment. It not only reduces the waste of raw materials, but also improves the utilization efficiency of limestone, so that the quality can meet the production requirements, and at the same time, it can make progress The change of CaO content in limestone from 10% to 4%.

        Homogenization measure 3: intelligent limestone stacking mode

        According to the past experience, when the mine limestone enters the plant, due to the different uniformity of limestone particles and the influence of the stacking mode of blanking, the material collapse and segregation are easy to occur on both sides of the material pile, resulting in the stacking shape unable to match the angle of the scraper, causing the sudden change of composition as high as 16 hours, affecting the back-end process operation.

        The project team collected the information of the walking wheel and cantilever height of the limestone stacker, optimized and rewritten the PLC program, redesigned the trolley detail equipment, created the intelligent stacking mode, made the stacking shape of the material stack consistent with the scraping equipment, effectively improved the stability of scraping composition, and optimized the limestone Cao change to 2% at one stroke. At the same time, it also solved the problem of material head loss since the start of the plant The firing problem caused by the quality difference of limestone in the tailings.

        Homogenization measure 4: automatic batching and precise quality control

        The calculation and adjustment of raw material ratio is one of the key points in the process of cement raw meal production. Any mistake may lead to serious quality out of control. In order to maintain stable production, Hualien plant adopts automatic batching system for raw material allocation. First of all, the semi-automatic grinding sample preparation system and X-ray analysis equipment in the laboratory were used to accurately analyze the chemical composition of samples in a few minutes. The proportioning system completes the proportioning calculation according to the quality target of raw meal, and transmits it to the field equipment through PLC program synchronously, so as to automatically adjust the proportioning of the weighing machine, so as to replace the previous manual calculation and adjust the proportioning through contact, greatly reduce the human error, and effectively improve the production efficiency. The change of limestone calcium oxide also decreased from 2% to 1%.

                Asia Cement Corporation has been a model student in China's cement industry for more than 60 years since its establishment, no matter in R & D, quality control, industrial safety, environmental protection and other aspects. This time, with the brainstorming of the project team, a series of homogenization measures have been put forward, which not only makes the raw meal quality more stable, but also reduces the dependence of the factory on purchased raw materials, and greatly saves operating costs. On the other hand, through intelligent mining and various planting methods, it accelerates the mine landscape restoration and soil and water conservation, and truly realizes the promise of sustainable green home. It can be called a model of Intelligent Manufacturing in cement industry!

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