Drinking water purification and treatment

Drinking water and its purity is an irreplaceable resource for the functioning of human society and ecosystems. Lime-based products are used to purify drinking water. One of these is lime milk, which removes organic substances or trace elements of toxic heavy metals from water.

Lime also softens and remineralises the water and ensures the balance of calcium carbonate in the water use cycle. Excessive water acidity can damage water infrastructure, particularly metal pipes. Conversely, if the water is too hard (alkaline), limescale will form. Lime milk is the most common way to adjust the pH.

Process Water Treatment

Process water is used in many industries. An important characteristic of process water is its low hardness. If it is too hard, lime scale will form, which can damage industrial cooling equipment, for example.

The most cost-effective way to soften water is to precipitate bicarbonates, which increase the hardness of the water, with lime milk, a suspension of fine calcium hydroxide particles.

Waste water treatment

Wastewater is produced not only by industrial plants, but also by municipal sources, institutions, hospitals and ordinary residential areas. In order to return used water to nature, it is treated using a range of physical, chemical and biological methods. In the case of industrial sources, special treatment processes are required. 

Acidic wastewater is neutralised with an alkaline agent that raises the pH. These processes also remove unwanted metals such as copper, nickel, cadmium and lead from the water, some of which are toxic to the environment.

Their removal also involves the use of a precipitant, which converts the toxic metal ions into insoluble particles that are then removed from the water by sedimentation or filtration. The most commonly used precipitant is calcium hydroxide. The advantage of using calcium hydroxide is also its affordability.

Lime and its products are also used in the treatment of sludge produced during wastewater treatment. Lime facilitates the drying of both organic and mineral sludges by improving their structure. It also disinfects and removes unpleasant odours. Treated sludge can be reused in agriculture as fertiliser.

Contaminated land treatment

The most common substances that contaminate soil are petroleum products, industrial solvents, pesticides and toxic metals. The risk of soil contamination arises mainly in areas of intensive industrial production, particularly in the chemical industry. Lime and its products are most commonly used to neutralise these substances when they are released into the environment.

High supply flexibility

A reliable supply of lime is essential not only for the maintenance of industrial plants, but also for compliance with strict flue gas cleaning regulations, which carry heavy penalties for non-compliance.

Cemix's top priority is therefore to ensure continuity and security of supply for its customers and partners. Thanks to its advanced logistics and high stock levels, the company is able to deliver large quantities of lime at short notice, in accordance with the exact requirements of its customers and business partners.

Flexibility is also essential as the consumption of lime and limestone in flue gas cleaning is significantly higher in the winter months than at other times of the year. For the transport of ground limestone and lime, Cemix has its own Raj wagons and keeps sufficient quantities of limestone in stock for immediate dispatch, which can easily cover even a large unexpected consumption of these products by the customer.

Another undeniable advantage of lime and lime products, apart from their affordability, is their biodegradability and minimal toxicity to the environment. They are therefore used in other environmental technologies.

Cemix is proud to support companies that remediate the effects of mining activities, such as uranium or coal mining, thus contributing to the improvement of the environment in regions that have been burdened in recent decades by often very unsustainable mining activities.

Flue gases are produced by various industries, particularly the energy sector and the incineration of municipal and industrial waste.

Flue gases contain pollutants such as sulphur dioxide, hydrogen fluoride or hydrogen chloride, nitrogen oxides, heavy metals and dust particles. Lime or limestone, which are very effective at removing acid gases, are the most commonly used products to capture them. For this reason, over 95% of European incinerators use these products in their operations.

Calcium oxide effectively removes sulphur oxides in the flue gas to form calcium sulphate, thereby reducing emissions. Calcium sulphate, also known as gypsum, is used in the construction, paper and agricultural industries as a fertiliser.

Flue gases, a special type of combustion gas, are produced by the burning of coal and waste in many industries. They typically contain sulphur oxides, hydrochloric and hydrofluoric acids, heavy metals or dioxins. Lime products are highly effective in removing these.

Flue gas neutralisation is carried out in several ways. The dry method uses ground limestone in the form of dry powder. This method is widely used by heating and incineration plants using fluidised bed boilers. Semi-dry technologies use the injection or spraying of lime milk, which lowers the temperature of the flue gases and adjusts their humidity.

In the wet process, the gases are cooled to the point where they begin to condense. The precipitated acid gases are cleaned with lime milk or calcium carbonate suspension. This method is more costly and is used in large plants.