About zinc:
Modern life is impossible without zinc, and at the same time, zinc is at the heart of the galvanizing process.
Zinc provides an economical and environmentally friendly way to protect metal from corrosion. By protecting metal, zinc helps conserve natural resources such as iron ore and energy. By extending the life of metal, zinc extends the life of capital investments. In the case of zinc coating infrastructure structures, it helps save taxpayers money.
In addition to protecting metal from corrosion, zinc has many other applications:
- in brass and other alloys;
- in automotive equipment, household items, tools and toys;
- in construction and modeling;
- in the pharmaceutical industry, medical equipment, cosmetics;
- in tires and rubber products;
- in fertilizers and feed additives.
Zinc is an essential element for human health and for all living organisms.
Environmental responsibility of the First Ukrainian Zinc Plant:
To create appropriate working conditions at the hot-dip galvanizing plant, preserve the health of personnel, and ensure production safety, the First Ukrainian Galvanizing Plant has developed a comprehensive approach that combines the latest technologies, high-quality equipment, and minimal environmental impact. At all stages of the hot-dip galvanizing process, reliable, multi-stage emission cleaning methods are used that protect both the company’s employees and the environment. High-quality, reliable components are used in the cleaning and regeneration systems.
Our modern technological line, unlike traditional surface preparation systems, does not use water to rinse products after the degreasing process before galvanizing, thanks to which we limit water pollution. Moreover, all waste generated during the chemical preparation process (metal pickling before the hot-dip galvanizing process) is transferred to specialized enterprises for further use. Therefore, the hot-dip galvanizing plant Persha Ukrainka Zinkovnya does not discharge any effluents into the sewerage system.
During the hot-dip galvanizing process, when metal products are immersed in a galvanizing bath, the so-called “white smoke” is released. This smoke is the products of flux boiling off the surface of the products being galvanized, it consists of ammonium chloride and zinc oxides.
At our production, we clean the “white smoke” using a system of modern German-made bag filters. The “white smoke” is sucked into a filtration system with a capacity of 40,000 m³/h during the immersion of the products.
The main element of the air cleaning unit is a system of fabric bag filters. Also, an additional filtering function is played by a layer of primary dust from the cleaned gases. Cleaning of the filter fabric occurs in automatic mode, the collected dust is shaken into a collection hopper and disposed of or reused. The use of a system of bag filters ensures compliance with all environmental requirements and is a convenient technical solution.
At our company, we use every opportunity to improve the environment. We use heat recovery systems from the exhaust gases of the zinc furnace to heat the office premises. We also collect rainwater and use it in the summer to water the green spaces and lawns located on the factory premises.
Zinc is a natural element
Zinc is a part of nature. A huge number of ores and minerals contain zinc in varying amounts, and zinc is also present in air, water, and soil as a result of natural processes. In some places, due to specific geological and geochemical processes, zinc is found in high concentrations, forming the ore from which zinc is extracted. Zinc metal is produced from ore and secondary zinc. In fact, 30% of the zinc used in the world today is obtained from secondary zinc. Natural
Processes such as the aging and modification of mountains, soils, and the formation of sedimentary rocks, as a result of the interaction of water and wind, contribute to the constant formation and accumulation of small amounts of natural zinc in the environment. These processes, which ensure the zinc cycle in nature, are the cause of the appearance of background levels of zinc in the air, groundwater, and soil.
This table shows the level of natural zinc content in air, soil, and rocks.
| Zinc content | ||
|---|---|---|
| Air (rural) | 0.01-0.2 | mg/m³ |
| Soil (average) | 10-30 | mg/kg |
| Volcanic rock | 5-240 | mg/kg |
| Clay shale | 18-180 | mg/kg |
| Sand | 2-41 | mg/kg |
| Black clay shale | 34-1500 | mg/kg |
| Zinc ores | 5- more than 15 | % |
This table shows the zinc content in oceans, rivers, and lakes.
| Zinc content | ||
|---|---|---|
| Open ocean | 0.001-0.06 | mg/kg |
| Coastal waters | 0.5-1 | mg/kg |
| Plain rivers | 5-40 | mg/kg |
| Mountain rivers | < 10 | mg/kg |
| Great Lakes | 0.09-0.3 | mg/kg |
| Streams passing through ore rocks | > 200 | mg/kg |
Zinc is essential for life
All life on earth develops in the presence of natural zinc compounds, because zinc is found in all organisms; it plays an important role in many biological reactions. It can be concluded that zinc is an essential element for all living things, from humans to microorganisms. Organisms take the elements they need from the environment: air, water, soil and food. When the need for these elements is met, the growth and development of the organism proceeds optimally. Deficiency occurs when the content of elements is very low and, in this case, undesirable results are often observed. On the other hand, too much of an element can lead to poisoning. Each organism has its own individual concentration range for each essential element that meets its needs. Thus, an optimal range of zinc concentration exists for every living organism, including humans.
Zinc is essential for human health
Zinc plays an important role in the metabolic process in the human body.
For example, zinc is necessary for the existence and normal functioning of more than 200 enzymes, which are necessary for stabilizing DNA and also for transmitting signals in the human nervous system. On average, each healthy person contains 2-3 grams of zinc and it can be found throughout the body. The highest content of zinc is in the muscles, liver, kidneys, bones and (in men) in the prostate. The recommended daily intake of zinc for an adult woman is 12 mg/day, and for an adult man it is 15 mg/day, because men are usually heavier than women. However, growing infants, children, adolescents, pregnant women and the elderly consume more zinc than would be expected from the proportion of their weight. Pregnant women need 25-50% more zinc than other women.
Food is one of the most important sources of zinc for humans, but foods vary in their zinc content. The main sources of zinc in your diet should be: red meat, poultry, fish, seafood, grains and dairy products. Despite the fact that zinc is essential for human health, studies show that many people do not get enough of it from food. Zinc, as a dietary supplement, can successfully balance your diet and compensate for zinc deficiency in the body, but too large doses can cause gastrointestinal disorders and are not recommended without consulting a doctor.
Plants and animals also need zinc
In the process of evolution, all living things on earth have used zinc from the environment for their specific functions related to metabolism.
Therefore, all organisms are adapted to the biologically available concentrations of zinc in their natural environment, which are subject to seasonal changes. Organisms have developed a mechanism called homeostasis that allows them to regulate their zinc needs (uptake) within these changes. In the natural environment, zinc deficiency is not possible, since nature provides zinc at a background level, but zinc deficiency can occur under artificial conditions such as those found in modern agriculture. In such cases, the biological availability of zinc has been reduced and zinc supplementation is necessary to obtain optimal growth of agricultural plants and animals.
Zinc in the aquatic environment
Some people are concerned about the effects of zinc on small organisms that live in freshwater; this has led to controversy over the methodology for assessing risk concentrations of such vital elements as zinc. Analysis of data on zinc content in soil has led to the conclusion that, at present, zinc levels do not represent any safety for the environment. For example, the current level of zinc in the Rhine is within the optimal concentration range for aquatic life, although in the past this river was polluted by industrial waste. In fact, most of the zinc in the Rhine comes from natural sources and is part of the natural ecosystem on which aquatic life depends.
Zinc is recyclable
Zinc can be recycled. Currently, about 30% of the world’s consumption is provided by secondary zinc. In other words, 2 million tons of zinc are recovered and reused every year. Secondary zinc is obtained from used products, such as: brass fasteners and fittings, zinc mold parts and galvanized steel obtained by recycling from old cars and household appliances. Zinc is also obtained from industrial waste, such as: galvanizing waste, furnace ash, offcuts, steel mill waste and brass scrap. The brass industry alone recycles about 6 million tons of zinc annually. It is very difficult to determine the exact amount of zinc recycling because most zinc products have a very long shelf life.
For example, zinc sheets used for roofing last about 100 years before being recycled. An estimate based on consumption history and product lifespans suggests that 80% of the total zinc that is recycled is actually reused. This is due to the nature of zinc, which does not lose its physical and chemical properties during recycling.
What happens to zinc in the environment?
Most of the zinc found in surface waters ultimately ends up in river sediments, settling in river inlets and coastal areas of the seas, where it combines with other substances that reduce its biological availability (bioaccumulation). The degree of bioaccumulation is of great ecological importance. Many factors, such as temperature, water hardness, pH and dissolved organic carbon content, determine the composition and degree of bioaccumulation of zinc in water. Zinc usually forms compounds with suspended organic matter and settles to the bottom. Based on this, the surface of the sediment reflects the level of zinc in the water above. Sedimentary layers that have formed in recent years show a decrease in zinc levels, as a result of a decrease in the level of industrial waste. Zinc enters the soil in various ways. Various factors determine the composition of zinc in the soil and, of course, its biological availability to other organisms.
Conclusion
Zinc is a natural element that is essential for humans and many living organisms. In fact, zinc deficiency can lead to human health problems. Zinc emissions from industry have decreased significantly in recent decades and currently do not pose a risk to the environment. Recently, the International Programme on Chemical Safety, a global forum under the auspices of the World Health Organization, the International Labor Organization and the United Nations Environment Program, has formulated an urgent task on zinc to establish Environmental Health Criteria. The task involves:
“Zinc is an essential element in the environment. It is possible to have both excess and deficiency of this metal.” Therefore, it is important that regulatory criteria for zinc, which are aimed at combating toxic pollution, are not set so low that their levels fall into the deficiency range.