Rock solid contribution

Published 12 November 2019

With limestone, dolomite and gabbro deposits totalling a combined production of over 80Mta and reserves of over 4.5bnt, Stevin Rock is a key global producer of crushed rock. Its quarries in the United Arab Emirates (UAE) supply in a sustainable way a wide range of products to a multitude of customers across the world. By Stevin Rock, UAE.

Stevin Rock’s Khor Khuwair quarry has a production capacity of over 60Mta

Together with its sister company RAK Rock, Stevin Rock is one of the largest crushed rock producers in the world. With a current production capacity of 80Mta of limestone, dolomite and gabbro the company’s three sites produce a range of products, from fine sand to coarse aggregates. The quarries supply asphalt,  and ready-mix plants, as well as feedstock for the cement, steel, chemical, glass and mining industries. Other uses include land reclamation, white beach sand, armour rock for sea defence/breakwater marine projects for the construction industry.

Key projects that have used Stevin Rock products include the Burj Khalifa in Dubai, Abu Dhabi and Dubai airports, the iconic islands of Palm Jumeirah, The World, Palm Jebel Ali in Dubai as well as the Al Zour refinery in Kuwait and Matarbari coal-fired power plant in Bangladesh.

The company is wholly owned by the government of Ras Al Khaimah, UAE. It employs over 3500 staff and has continuously expanded for over 41 years.

Major cement industry contributor

Stevin Rock supplies various grades of limestone to the cement industry in the UAE and further afield. The product supplied is available in a range of sizes (fine 0-5mm, 0-20mm, 0-30mm, or coarse 30-60mm and 60-80mm) to adapt to all types of grinding units.

High-resolution drone topographical surveys contribute

to the company’s quality assurance system

High-grade Stevin Rock limestone is perfect for making white cement as it is low in silica (SiO2 <1 per cent) and iron oxide (Fe₂O₃ <0.1 per cent), high in calcium oxide (CaO >54 per cent) and contains only trace amounts of oxides of titanium, manganese and chrome (TiO₂, Mn₂O₃ and Cr₂O₃).

The limestone is also ideal for the manufacture of grey cement thanks to a controlled calcium oxide (CaO) content of 50 ±1 per cent, which optimises the clinker phase formation. Moreover, less silica sand, iron ore and bauxite are needed due to the relatively-high content of silica (2.5-5 per cent of SiO2), iron oxides (0.25-0.5 per cent Fe₂O₃) and aluminium oxides (0.75-1.50 per cent Al₂O₃) in the company’s limestone.

Quality control to meet international standards

With three quarries producing considerable volumes of limestone, dolomite and gabbro together with 34 distinct crushing lines, supplemented by extensive screening and washing plants for special products, Stevin Rock has the capacity to ensure a reliable supply across a wide range of physical and chemical products characteristics.

Its independent technical services department tests and certifies the quality of the entire product range at its own laboratory. The department has stringent and accredited quality control procedures to guarantee full compliance with both local and international quality standards, including ASTM, EN, CIRIA and BS.

In addition, computer-aided quarry design and production management, high-resolution drone topographical surveys and state-of-the-art analytical equipment covering every stage of operations – from geological investigations through drilling, blasting, hauling and crushing to shipping by land or sea – all contribute to the company’s quality assurance system.

The crushed rock producer has been awarded international management system standards such as ISO 9001:2015 (Quality Management), ISO 14001:2015 (Environmental) and ISO 45001:2018 (Health and Safety). It also complies with the requirements of the Framework Standard for Responsible Sourcing BES 6001: Issue 3.0.

The largest hydraulic shovel in the Middle East at work

Sustainability in mind

Stevin Rock is dedicated to sustainable development of the company and its natural resources. This is assured through comprehensive programmes for protection of the environment, engagement with communities, and the health, safety and welfare of employees – all underpinned by delivering a robust economic performance. Environmental control and protection measures typically account for 10 per cent of the company’s capital expenditure, while health, safety and environment expenditure is a fundamental and major element in operating costs.

Reducing the impact of its operations

Stevin Rock is continuously striving to improve its efficiency while reducing the environmental impact of its operations. Increasingly-larger mobile equipment is used to reduce the number of haul cycles. At Stevin Rock’s Khor Khuwair quarry, the largest limestone quarry in the world with a production capacity of over 60Mta, no less than 429 pieces of mobile equipment operate, including 95x 60t and 110x 100t haul trucks, 100x 75t articulated trucks, a large number of dozers, loaders and shovels with a 240t prime loading excavator, the largest in operation in the Gulf region.

To further reduce the environmental impact and cost of its quarry vehicles, the company has its own tyre factory with state-of-the-art equipment able to retread all types of tyres used on its heavy mobile equipment fleet.

Desalinated seawater spraying takes place throughout

all stages of quarry operations to reduce dust emissions

In addition, an extensive network of over 10km of in-pit conveyors operates at Khor Khuwair, some of them generating electricity, to partly replace hauling trucks and to further reduce the carbon footprint of the quarry’s operations.

To mitigate dust emissions, several measures have been taken by the company: advanced dust extraction systems across all of its quarries, encapsulation of all crushers, screens, product bins and conveyor systems, desalinated seawater spraying throughout all stages of its operations and selective use of biodegradable dust suppressants.

Staff training

Management and staff collaborate closely to maintain and develop operational excellence, efficiency and profitability of Stevin Rock operations. The company empowers its employees and develops their abilities through regular training in the use of the latest equipment and technologies.
International consultants visit regularly to provide personal professional training and support, and Stevin Rock’s training centre includes two heavy mobile equipment simulators, the only ones in the region.

Growing geographical reach

Over 40Mta of various types of Stevin Rock products are currently exported to Kuwait, Bahrain, Iraq, India, Bangladesh, Ukraine and Madagascar. More recently, the company has also exported armour and core rock to Bangladesh for coastal construction projects.

Furthermore, Stevin Rock continues to investigate new export markets including China, Thailand and Singapore. A 55,000t trial shipment of manufactured limestone sand for land reclamation in Singapore was successfully completed in August 2018.

Strategic export location

The Khor Khuwair limestone quarry is connected to the adjacent government-owned Saqr port. Saqr port is one of the largest ports in the Gulf region, handling more than 70Mta of freight, mostly dry bulk cargo, including Stevin Rock crushed rock products.

In the 4Q18 and 1Q19 Saqr port commissioned two 18m-deep water berths for a combined quay length of 700m, suitable for Capesize vessels in addition to eight 12.2m-deep berths able to accommodate Panamax vessels. The use of Capesize vessels, together with backhaul cargoes, will enable Stevin Rock to reduce shipping costs, reach more-distant markets and expand its export business.

Loading sand for export at Saqr port

In addition, Stevin Rock and its logistics partners are able to handle and load the full range of stone products, including armour rock up to 8t, into specially-designed 44,000dwt bulk carriers. Furthermore, barges of up to 26,000dwt can also supply crushed rock products to Dubai, Abu Dhabi and the Gulf countries from Stevin Rock harbour, which is located next to Saqr port.

Therefore, the company benefits from internationally-competitive CFR costs as a result of combining seamless logistics with large production volumes that minimise fixed costs per tonne.
Over the years, a large number of world-class construction projects in the UAE and the rest of the world have used Stevin Rock products, bearing witness to the company’s supply of high-quality products, its competitiveness and capabilities.

This article was first published in the November 2019 issue of International Cement Review.