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Study on phosphorus release from medium- and low-grade phosphate ore powders by mechanical activation and low molecular weight organic acid activation

Fan Tingyu, Ma Tenglong, Wang Miao, Wang Shun, Wang Xingming, Lu Akang

Physicochemical Problems of Mineral Processing

2024

Vol. 60, iss. 1

art. no. 183275

Phosphate ore is an essential resource for producing phosphate fertilizer. International phosphate ore is overmined, and phosphorus resources are becoming depleted; improving the utilization efficiency of medium- and low-grade phosphate ore powder (PR) through activation is the key to the sustainable and efficient use of phosphorus resources. However, the traditional activation method is inefficient and has some limitations on the grade of phosphate ore. In this study, a combination of mechanical activation and low molecular weight organic acid activation was used to activate medium- and low-grade phosphate ore powders, and the activation effects of different mechanical activation conditions, such as mechanical grinding time, the addition of different types and proportions of active minerals (zeolite, bentonite, and kaolin), and different types of low molecular weight organic acids (oxalic acid, tartaric acid, malic acid, and citric acid), on phosphate ore powder were compared. The results show that mechanical activation had a synergistic effect with low molecular weight organic acid activation. Mechanical activation can reduce the particle size of phosphate ore powder and increase the release of effective phosphorus from phosphate ore powder. Mechanical activation for 60 min reduced phosphate ore powder's median diameter (D50) from 41.67 μm to 10.59 μm and increased the effective phosphorus leaching rate from 1.19% to 8.27%. The phosphorus release effect of low molecular weight organic acids was oxalic acid > tartaric acid > malic acid > citric acid, with the optimal concentrations of 0.1 mol/L, 0.3 mol/L, 0.5 mol/L, 0.2 mol/L, and the optimal activation cultivation times were all 6 days. This study optimizes the activation method of phosphorite powder, which can not only alleviate the current global shortage of phosphorite resources but also reduce environmental pollution while maximizing the use of phosphorite resources.

Research on a mining area risk management system based on internal control theory

Mu Hailong, Meng Shangjiu, Wang Miao, Zhang Shengjun

Gospodarka Surowcami Mineralnymi

2023

T. 39, z. 4

49--66

Based on China’s resource endowment and coal mine disaster statistics, it has been found that there are many deficiencies in the management of disasters and risks in mining areas in China. Therefore, to scientifically and effectively manage mining areas, based on the theory of internal control, this paper systematically analyzes the risks of mining areas in the context of various factors and relevant suggestions. From the occurrence of mine risk to the occurrence of damage, the importance of risk management is highlighted. In accordance with the five selection principles of evaluation indicators (goal principle, comprehensiveness principle, scientificity principle, timeliness principle and focus principle) as well as the five elements of internal control (control environment, risk assessment, control activities, information and communication and supervision), a mining area risk management framework of human-machine-environment-management – disturbance is constructed, and twenty-seven secondary risk indicators are divided. The criteria for determining the risk level and the risk response process have been established, and a more systematic and accurate mine risk management system under the theory of internal control has been formed. Finally, based on four key technologies, a dual prevention and control mechanism is formed around the system risk and job risk management system. This provides new methods and ideas for the prevention and control of coal mine safety risks and the containment of disasters and accidents.

Na podstawie chińskich zasobów i statystyk dotyczących katastrof w kopalniach węgla stwierdzono, że istnieje wiele niedociągnięć w zarządzaniu katastrofami i ryzykiem na obszarach górniczych w Chinach. Dlatego, aby naukowo i efektywnie zarządzać obszarami górniczymi, w oparciu o teorię kontroli wewnętrznej, w artykule systematycznie analizuje się ryzyko obszarów górniczych pod kątem różnych czynników i odpowiednich sugestii. Od wystąpienia ryzyka górniczego do wystąpienia szkód podkreśla się znaczenie zarządzania ryzykiem. Zgodnie z pięcioma zasadami wyboru wskaźników oceny: zasadą celu, zasadą kompleksowości, zasadą naukowości, zasadą terminowości i zasadą ukierunkowania, a także pięcioma elementami kontroli wewnętrznej: środowiskiem kontroli, oceną ryzyka, działaniami kontrolnymi, informacją i komunikacją oraz nadzorem, skonstruowano ramy zarządzania ryzykiem w obszarze górniczym w zakresie zakłóceń w zarządzaniu ludźmi, maszynami i środowiskiem oraz podzielono 27 drugorzędnych wskaźników ryzyka. Ustalono kryteria określania poziomu ryzyka i proces reagowania na ryzyko, a także stworzono bardziej systematyczny i dokładny system zarządzania ryzykiem kopalnianym w ramach teorii kontroli wewnętrznej. Wreszcie, w oparciu o cztery kluczowe technologie, stworzono podwójny mechanizm zapobiegania i kontroli ryzyka systemowego i systemu zarządzania ryzykiem zawodowym. Zapewnia to nowe metody i pomysły w zakresie zapobiegania i kontroli zagrożeń bezpieczeństwa w kopalniach węgla oraz ograniczania katastrof i wypadków.