What Is Involved in Manganese Mining?

In modern industry, manganese and its compounds are used in various fields of the national economy. Among them, the iron and steel industry is the most important field, with 90% to 95% of manganese. It is mainly used as a deoxidizer and desulfurizer in iron and steelmaking processes, and used to make alloys. The remaining 10% ~ 5% of manganese is used in other industrial fields, such as chemical industry (manufacturing various manganese salts), light industry (for batteries, matches, printing paint, soap making, etc.), building materials industry (glass and ceramic Colorants and discolorants), defense industry, electronics industry, environmental protection and agriculture and animal husbandry, etc. In short, manganese has a very important strategic position in the national economy.

Manganese is one of the essential trace elements in the human body.

Manganese absorbed by the human body is absorbed in the intestine and is mainly distributed in the muscles, kidneys and brain. Manganese is a component of many enzymes in the human body, plays an important role in cell metabolism, and has a close relationship with human health.

When the intake of manganese in food is insufficient, too much calcium, phosphorus, iron and other components in food interfere with the absorption of manganese, or digestive diseases interfere with the absorption of manganese, which can cause manganese deficiency. Manganese deficiency can cause the following lesions:

Osteoporosis, skeletal deformity, cartilage damage, middle-aged and elderly people have fatigue and fatigue, back pain, premature tooth loss, and easy fracture; children have stunted growth and skeletal deformity.

Peroxide dismutase in the human body has anti-aging effects. This enzyme contains manganese. When manganese is lacking, it has no anti-aging effects.

A severe lack of manganese in the human body can cause infertility, and even stillbirths and deformed children appear. Male male hormone secretion is reduced.

The normal function of the brain requires manganese. When manganese is lacking, it can cause mental retardation, ADHD in children, and even induce epilepsy and schizophrenia.

Manganese poisoning

Manganese is an off-white, hard, brittle, and shiny metal. Manganese is widely found in nature. The soil contains 0.25% of manganese. Tea, wheat, and hard-shell fruits contain more manganese.

Manganese-exposed operations include crushed stone, mining, electric welding, production of dry batteries, and dye industry.

Manganese is one of the essential trace elements that is essential for the normal body. It constitutes several enzymes with important physiological functions in the body. Normally, 3-9 mg of manganese is taken from food every day.

Occupational manganese poisoning is caused by long-term inhalation of manganese smoke and manganese dust with high manganese depth. Chronic manganese poisoning is the main type of occupational manganese poisoning. It is more common in workers who work in ferromanganese smelting, welding electrode manufacturing and welding, and mining, crushing or producing dry batteries.

Clinical manifestations: slow onset, onset working age is generally 5-10 years, there are also people who have not worked for more than 20 years, which may be related to individual sensitivity, early mild manifestations include poor mentality, insomnia, dizziness, headache, weakness, sore limbs , Memory loss and other symptoms, some people are easily excited, talk too much, crying and other emotional changes, often with poor appetite, nausea, salivation, epigastric discomfort, decreased libido or impotence, sweating, etc., sometimes limbs numbness and pain 2, legs are heavy and weak.

In addition to the above symptoms of moderate poisoning, I feel that my legs are heavy, benzene, slow walking, easy to fall, slurred speech, stuttering, and difficult to perform fine movements. Severe poisoning and worsening symptoms, limbs stiff, confusing speech, tremor in the jaw, lips, and tongue; in writing test, the smaller and smaller the word, called "writing too small"; the mental symptoms are autonomous crying pen, memory loss Smart decline.

If you are diagnosed with chronic manganese poisoning, you should get rid of the manganese and go to the hospital for manganese removal treatment.

Mine mining, blasting, crushing, screening and other processes use wet operations, such as drilling with water drills, blasting with water seals, spraying dust to reduce dust flying. The workshop adopts mechanical ventilation or natural ventilation to reduce the concentration of manganese dust in air defects, mixing materials, sieving, etc. during the production of flux, welding rods, and storage batteries, and adopts closed and vacuum devices to avoid flying manganese dust. Strengthen personal protection, filter masks, clean before meals, preventive physical examination, early detection and early treatment.

Manganese nutrition perspective

Manganese is widely distributed in the biosphere, but its content is very small in humans. The total amount of manganese in adults is about 200-400 mol, which is distributed in various tissues and fluids of the body. The concentrations of manganese in bone, liver, pancreas and kidney are higher; the concentrations of manganese in brain, heart, lung and muscle are lower than 20nmol / g; the concentrations of manganese in whole blood and serum are 200nmol / L and 20nmol / L respectively. The concentration of manganese in the mitochondria is higher than that in the cytoplasm or other organelles, so the tissue with many mitochondria has a higher manganese concentration.

Discovery of Manganese

In the second half of the 18th century, Swedish chemist TO Bergman studied soft manganese ore and regarded it as a new metal oxide. He tried to separate the metal without success. Scheler also did not extract the metal from the soft manganese ore, so he turned to his friend, Bergman's assistant, Gan Ying. In 1774, Gan Ying separated the metal manganese. Bergman named it managnese (manganese). Its Latin name manganum and the element symbol Mn came from this. Manganese was known to be a component of animal tissues in 1913, but manganese deficiency was found in various experimental animals only in 1931, thus confirming that manganese is one of the essential trace elements for animals.

Food source

Cereals, nuts, and leafy vegetables are rich in manganese. Manganese is the most abundant in tea. Refined cereals, meat, fish, and milk contain less manganese. Although animal-based foods are not high in content, they have high absorption and retention, and still do not lose a good source of manganese.

Metabolic absorption

All small intestines can absorb manganese. The absorption of manganese is a rapid and saturable process, which is likely to be accomplished by a high-affinity, low-volume active transport system and an unsaturated simple diffusion effect. The absorption mechanism of manganese may include two steps. First, it is taken from the intestinal cavity, and then it is transported across the mucosal cells. The two dynamic processes occur simultaneously. During the absorption process, manganese, iron and cobalt compete for the same absorption site. Any high amount of the three will inhibit the absorption of the other two. Manganese is excreted almost completely through the intestine, with only a small amount excreted in the urine. Absorbed manganese is excreted very quickly through the intestines.

Physiological function

Part of manganese in the body acts as a component of metalloenzymes, and part of it acts as an enzyme activator.

Physiological needs

The appropriate intake of manganese for adults is 3.5 mg / d, and the maximum tolerable intake is 10 mg / d.