Decarbonisation Technology May 2025 Issue

CO 2 capture

Cement factory

CO transport

CO storage

Figure 2 Carbon capture and storage schematic

x Carbon capture utilisation and storage Carbon capture and storage (CCS) or carbon capture, utilisation and storage (CCUS) technologies are critical to reducing the industry’s carbon footprint. However, capturing CO₂ from the high-temperature flue gases of cement kilns presents technical challenges. The flue gases should be cooled before CO₂ can be captured, which involves further energy input. Additionally, for CCS to be effective, precise thermal management is required. The process of capturing CO₂, whether through post-combustion, oxy-fuel combustion, or pre-combustion technologies, involves several temperature-sensitive steps. Maintaining optimal temperatures is crucial for the efficiency of solvents, membranes, or other capture mediums. Any deviation from the required temperature range reduces the CCS efficiency and increases its energy consumption. Role of heat tracing Heat tracing involves the application of electrical heating cables to pipes, vessels, and other equipment to maintain or elevate temperatures to a desired level. In the context of the cement industry, heat tracing solutions are instrumental in addressing several challenges outlined above. u Enhancing energy efficiency Heat tracing systems can significantly improve the energy efficiency of cement plants by minimising heat loss in critical areas. For instance, in the clinker production process, heat tracing can be applied to maintain the temperature of raw materials and prevent heat loss during transportation through preheaters, kilns, and coolers. This ensures that less energy is required to maintain the high temperatures necessary

for calcination, thereby reducing overall energy consumption and CO₂ emissions. Heat tracing can also be used to optimise the operation of heat exchangers and waste heat recovery systems, which are integral to improving energy efficiency in cement plants. By maintaining optimal temperatures in these systems, heat tracing helps maximise the recovery of waste heat, which can then be reused in the production process, further reducing the need for external energy inputs. v Supporting the use of alternative fuels The integration of alternative fuels into cement production processes requires careful thermal management to ensure consistent and efficient combustion. Heat tracing solutions can be employed to preheat alternative fuels with high moisture content, such as biomass, before they enter the kiln. This preheating reduces the moisture content of the fuel, improving its combustion characteristics and ensuring a stable and efficient burning process. As a result, the use of alternative fuels becomes more viable, helping to reduce the industry’s reliance on fossil fuels and lower its carbon footprint. w Optimising CCUS processes Heat tracing plays a crucial role in the optimisation of carbon capture systems. In post-combustion carbon capture, for example, flue gases must be cooled to a specific temperature range before CO₂ can be efficiently captured. Heat tracing systems can be used to precisely control the cooling process, ensuring that flue gases reach the required temperature Figure 3 Self-regulating heating cable maintains or elevates temperatures to a desired level