How is cement produced?
Concrete is one of the most important and commonly used materials in global construction. Concrete is widely used in the construction of both residential and commercial buildings, bridges, roads and more.
The key component of concrete is cement, a binding substance which binds all the other components of concrete (generally gravel and sand) together. More than 4 billion tonnes of cement is used worldwide every year, illustrating the massive scale of the global construction industry.
Making cement is a complex process, starting with raw materials including limestone and clay which are placed in large kilns of up to 120m in length, which are heated to up to 1,500°C. When heated at such high temperatures, chemical reactions cause these raw materials to come together, forming cement.
As with many industrial processes, cement production is not without its dangers. The production of cement has the potential to release gases which are harmful to workers, local communities and the environment.
What gas hazards are present in cement production?
The gases generally emitted in cement plants are carbon dioxide (CO2), nitrous oxides (NOx) and sulphur dioxide (SO2), with CO2 accounting for the majority of emissions.
The sulphur dioxide present in cement plants generally comes from the raw materials which are used in the cement production process. The main gas hazard to be aware of is carbon dioxide, with the cement making industry responsible for a massive 8% of global CO2 emissions.
The majority of carbon dioxide emissions are created from a chemical process called calcination. This occurs when limestone is heated in the kilns, causing it to break down into CO2 and calcium oxide. The other main source of CO2 is the combustion of fossil fuels. The kilns used in cement production are generally heated using natural gas or coal, adding another source of carbon dioxide into addition to that which is generated through calcination.
Detecting gas in cement production
In an industry which is a large producer of hazardous gases, detection is key. Crowcon offer a wide range of both fixed and portable detection solutions.
Xgard Bright is our addressable fixed-point gas detector with display, providing ease of operation and reduced installation costs. Xgard Bright has options for the detection of carbon dioxide and sulphur dioxide, the gases of most concern in cement mixing.
For portable gas detection, the Gasman’s rugged yet portable and lightweight design make it the perfect single-gas solution for cement production, available in a safe area CO2 version offering 0-5% carbon dioxide measurement.
For enhanced protection, the Gas-Pro multi-gas detector can be equipped with up to 5 sensors, including all of those most common in cement production, CO2, SO2 and NO2.