The Egyptian cement sector has suffered from a severe energy crisis over the last few years, where the supply of natural gas and/or fuel oil was not enough to sustain full production rates. In many cases, the plant operators were forced to reduce the kiln feed, and on several occasions they had to stop the kiln completely. This resulted in loss of production, as well as several other problems related to unsteady operational conditions, especially with regard to refractories. Cement plants that were producing their own electric power using diesel generators were the most affected by the energy crisis. Furthermore, as grinding imported clinker was not an easy task due to the limitations of the electric power grid, plants were forced to suspend their grinding mills. This article will discuss the utilisation of RDF, sewage sludge, agricultural wastes and oil shale as potential solutions to overcome the energy crisis.
Egypt is one of the oldest cement manufacturing countries in the region, with first production beginning in 1927 with the establishment of Torah Cement Company. Later, in 1929, Helwan Cement Company was set up, followed by Alexandria Cement Company in 1948 and National Cement Company in 1956. In the 1970s, the production capacities of the four cement companies totalled around 4 million t. The construction boom witnessed in the late 1970s and 1980s created high demand for cement, which was met through imports due to the limited local production capacities, despite the entry of three new cement producers into the market – Suez, Assiut and Amiryah – which began production throughout this period. In the mid 1980s, Egypt became one of the largest cement importing countries in the world.
During the 1990s, a further six cement firms were established to cope with increasing construction activity and the resulting cement demand, especially with the appearance of new suburban cities such as Al-Sherouq, Al-Obour and Al-Sadat. Egypt’s cement importing position prevailed during the 1990s and the early years of the 21st century. Consequently, cement producers in Egypt increased their production capacities and enhanced their production lines to meet the surging local cement demand. In 2002, Egypt was a net importer of cement; however, in 2004, Egypt stopped importing cement and became one of the largest cement exporting countries in the region.
Currently, the installed capacity of Egypt’s cement industry is approximately 62 million tpy. The industry consumes more than 9% of total primary energy in the country, making it the most energy-consuming sector. At present, most of the consumed energy in the cement sector is supplied in the form of natural gas or fuel oil, which is provided by the state at subsidised prices. Over the last few years, it became obvious that Egypt has a very low level of self-sufficiency in terms of both natural gas and fuel oil, with a clear trend of increasing the import of most energy types year after year. With a badly suffering budget and limited resources in terms of hard currency, the burden of subsidising energy to the cement sector is getting beyond the limits, especially if one considers the rapidly increasing global energy prices.
The production of Portland cement requires a high degree of thermal energy. Burning 1 kg of PZ-Clinker out of raw material components requires 1.75 MJ of thermal energy (basic calculation). This requirement is based on the endothermic reactions of the decarburisation of limestone and the dehydration of kaolinites (a value of approximately 2.20 MJ/kg) and an exothermal reaction of phase-forming (C3S, C2S, C3A and C4AF, value approximately 0.45 MJ/kg). The effective requirement of thermal energy is approximately 3.2 – 4.2 MJ/kg depending on the process efficiency, bypass ratio, false air and number of preheater stages, etc.
Energy is the blood of a modern lifestyle. The more technically advanced a state, the greater the energy consumption per capita. Egypt’s energy balance for 2007 indicates that the largest share of final energy consumption occurs in the industrial sector (34.2%), followed by transportation (24.2%), residential (18.8 %), and agriculture and mining (4.7 %) – together accounting for 81.9% of total consumption. By fuel type, oil products account for more than half of fuel consumption (54.1%), followed by natural gas (20.6%) and electricity (18.3%) – together comprising 93% of total demand. The remainder is non-energy use….
Read the article online at: https://www.worldcement.com/africa-middle-east/09062015/energy-crisis-in-the-egyptian-cement-sector-976/