Cementing Vision 2030

Last Updated 13 years ago by Kenya Engineer

Infrastructure is crucial to economic and social development.  Poor infrastructure impedes a nation’s economic growth and international competitiveness. Adequate supply of infrastructure services is an essential ingredient for productivity and growth. The Cement industry plays a major role if not the main role in Infrastructure development of any country. It is hence significant to analytically review and asses Kenya’s Cement industry in view of infrastructure development within the context of the way forward for meeting the outcomes of the country’s Vision 2030.

Kenya has maintained a stable macroeconomic environment and has, at the same time, been developing key infrastructure facilities and public works nationwide to stimulate growth. In the financial year 2010/11, the Kenyan government adopted a fiscal policy geared towards consolidating economic recovery and putting the economy back to the Vision 2030 targets.

Cement is the main ingredient for construction and infrastructure development.  According to data from the Kenya National Bureau of Statistics (KNBS), Cement consumption for the 11 months ended November last year hit a high of 2.8 million metric tonnes while supply for the 12 months ended December hit a record 3.7 million metric tonnes. This is the highest cement supply and production since 2006.

With new cement companies, the Kenya economy has begun to enjoy healthy economic development in terms of advancement of technology, eventually leading to realization of Vision 2030. According to Architectural Association of Kenya (AAK) officials the multi-billion technical cement plants now play a significant role in attainment of green technology that has increased national output. AAK says that in a move to compete for market of their products and improve efficiency, cement companies are investing in the most modern of technologies.

Consumers of building materials now consider the efficiency of getting the products and its quality rather than price, forcing investors to utilize new production and supply chain techniques that increase efficiency of their operations.

Among the technologies cement manufacturing plants are embracing is the use of back filters to trap dust from the crushed clinker and pozzollana, which is recycled as raw material, minimizing environmental hazard and reducing wastage.

Kenya’s cement industry, the largest in East Africa, benefits from increased government spending on infrastructure projects both within the country and in neighboring countries. Domestic consumption is growing at a faster rate than production, and Kenya’s market is expected to consume 81 percent of output in 2013.

According to a report published last year by Investment Bank Dyer and Blair, Kenya’s building and construction sector is amongst the most rapidly growing, experiencing an average growth rate of 14.2% for the period 2006 – 2011. While the cement industry, cement consumption in particular is highly correlated to a country’s economic performance, cement consumption experienced superior growth that was more than twice the rate of GDP growth during the period. Growing in tandem with the construction sector, cement consumption increased at an average rate of 14.1% for the period 2006 – 2011, with consumption reaching 3.43 million tonnes (mT) in 2011, up from 1.57mT in 2006.

The key drivers of this growth in consumption according to the report included rising demand for housing, the commercial construction boom fuelled by increased foreign investment, and extensive government and donor-funded spending on the country’s mega infrastructure projects.

Cement production expanded at an average rate of 11.6% for the period 2006 – 2011 to 4.09mT in 2011 from 2.41mT in 2006. This rise in production was driven by the entry of new cement producers and extensive capacity expansion by existing players in response to increasing competition. This rise in production led to the consistent oversupply of cement during this period. Given an estimated industry capacity utilization rate of about 72%, this glut supply could be much higher were installed capacity fully utilized.

Kenya’s Cement exports average 21.1% of total cement production with key export markets including Uganda, Tanzania, the Democratic Republic of Congo (DRC) and other East and Central African countries.

Imported cement accounts for a marginal 2% of total cement consumption indicating the country’s overall reliance on locally produced cement. In 2011, cement import duty under the East African Community Common External Tariff was lowered by 10% to 25% despite stiff opposition from industry players. Should the suspension of the 10% import duty remain, the quantum of cheap cement imports particularly from low-cost producers such as Egypt, India, China and Pakistan could increase considerably, further widening the demand-supply mismatch.

Summary of Cement production process
Cement is a fine powder which sets after a few hours when mixed with water, and then hardens in a few days into a solid, strong material. Cement is mainly used to bind fine sand and coarse aggregates together in concrete.  Cement is a hydraulic binder, i.e. it hardens when water is added.

There are 27 types of common cement which can be grouped into 5 general categories and 3 strength classes: ordinary, high and very high.  In addition, some special cements exist like sulphate resisting cement, low heat cement and calcium aluminate cement.

The quarry is the starting point
Cement is typically made from limestone and clay or shale. These raw materials are extracted from the quarry crushed to a very fine powder and then blended in the correct proportions. Cement plants are usually located closely either to hot spots in the market or to areas with sufficient quantities of raw materials. The aim is to keep transportation costs low. Basic constituents for cement (limestone and clay) are taken from quarries in these areas.Clinker is then produced from raw materials and the cement is produced from cement clinker.

Making clinker
The raw materials are delivered in bulk, crushed and homogenized into a mixture which is fed into a rotary kiln. This is an enormous rotating pipe of 60 to 90 m long and up to 6 m in diameter. This huge kiln is heated by a 2000°C flame inside of it. The kiln is slightly inclined to allow for the materials to slowly reach the other end, where it is quickly cooled to 100-200°C.

Four basic oxides in the correct proportions make cement clinker: calcium oxide (65%), silicon oxide (20%), alumina oxide (10%) and iron oxide (5%). These elements mixed homogeneously will combine when heated by the flame at a temperature of approximately 1450°C. New compounds are formed: silicates, aluminates and ferrites of calcium. Hydraulic hardening of cement is due to the hydration of these compounds. The final product of this phase is called “clinker”.

After cooling, the clinker may be stored temporarily in a clinker store, or it may pass directly to the cement mill.
The second phase is handled in a cement grinding mill, which may be located in a different place to the clinker plant. Gypsum (calcium sulphates) and possibly additional cementitious (such as blastfurnace slag, coal fly ash, natural pozzolanas, etc.) or inert materials (limestone) are added to the clinker. All constituents are ground leading to a fine and homogenous powder.  The cement is then stored in silos before being dispatched either in bulk or bagged.

What is concrete?
Concrete is a solid material made of cement, sand, water, aggregates and often with admixtures. When fresh, it has a certain workability and takes the form of the mould into which it is put. When set and hardened, it is as strong as natural stone and resists time, water, frost, mechanical constraints and fire. Typically, concrete is the essential material used in all types of construction.

Top Cement Manufacturers in Kenya
Top Cement Manufacturers in Kenya include; Bamburi Cement Limited of the Nguvu brands, ARM Cement Limited of the Rhino brand, East African Portland Cement Company Limited of the Blue Triangle brand, Savannah Cement of the Savannah brand, National Cement of the Simba brand and Mombasa Cement of the Nyumba brand.