First publishedin Aggregates Business Europe
As-Sweimeh is probably the lowest quarry on earth with its highest point at 150m below sea level. Claire Symes visited the quarry in Jordan to find out more
Although the quarry at As-Sweimeh has only been open for eight years, it is already the biggest quarry in Jordan and one of the biggest quarries in the Middle. But what makes it unusual is its altitude - lying within site of the Dead Sea which is the lowest point on Earth, the quarry's highest level is 150m below sea level.
As-Sweimeh produces around 900tonnes per hour and operates 24 hours a day to meet the demand for high quality aggregates in Jordan. As-Sweimeh was opened in 2005 45km east of Amman to exploit the limestone deposits but as the quarry was opened up, marble and silica sand deposits were also found.
The Manaseer Group
moved into quarry operation in 2002 when it wanted to be able to produce its own aggregates to supply its ready mixed concrete business. "We had experienced problems buying the aggregate sizes needed so it was an obvious step to create our own resource," said Advance Crusher Company deputy general manager Mahmoud Alsaidi. "Once the site was established, production was expanded to meet demand from the Jordanian construction market." The company's first quarry is at Aqaba and extracts granite which is processed with new mobile crusher from Sandvik
. The most recent addition to the portfolio is the Al-Hallabat quarry (see box) which is currently Jordan's only basalt quarry, which the company developed to try and improve the quality of road construction in the country.
Today, around 70% of the material extracted from As-Sweimeh goes to the concrete market. The company operates 200 trucks to transport aggregates to its own concrete facility and to its customers. The high quality of the material means that it is transported up to 200km but the average transport distance is 60km.
"The quarry employs 220 people and is the largest in Jordan," said Alsaidi. "As-Sweimeh is probably one of the largest quarries in the Middle East with only some in Dubai that are larger.
"The quarry operates 24 hours a day with three shifts - 20 hours of production and 4 hours of maintenance." Some of the extraction at the site is by blasting but other more loosely cemented areas of the limestone deposit are extracted by dozers. Each blast uses 50 drill holes to a depth of 9m with a 2.5m spacing with ANFO as an explosive. Blasting is carried out once a day to extract 5000m3
The quarry uses Cat 988 wheeled loaders to load the fleet of Belaz
trucks which haul the material to the feeder hopper of the 550 tonne per hour SBM
crusher which has a primary jaw crusher and a secondary cone crusher. The site also has a 350tonne per hour Nace rotary crusher. The site has 10 screens - five out of these are there to reduce the fines and improve the quality of the final product.
"Controlling dust is a focus for the plant and dust filters have been fitted which go beyond local regulations," explained Alsaidi. Trucks are loaded directly from the stockpiles created by the crushing and screening plant.
The quarry has three active faces - one for the silica sand, one for concrete aggregates and another for asphalt aggregates. Silica sand products are extracted directly by wheeled loader and screened within the quarry in a separate operation using dedicated screening equipment.
As well as a large number of employees, the quarry also has a large machine fleet with 56 machines. These include 18 from Caterpillar which are a more recent addition to the site.
The Cat machines are a recent arrival at the site - they directly replaced a fleet from another major manufacturer, not because they necessarily perform better on site but due to the level of service offered by the local Cat dealer Jordan Tractor.
According to Alsaidi, the company had experienced problems with the level of service from the previous manufacturer's dealer in terms of parts availability and responsiveness. "The Cat machines were more expensive to buy and service but the overall performance and cost per tonne has been better. We get 24 hour service and a higher productivity due to the higher availability.
"The environment here is very harsh due to the dust levels at the extraction face and because of the high summer temperatures which can reach up to 550C. These conditions make having Cat's service team on site invaluable." The quarry already occupies a 7million m2 area with 300,000 m2 occupied by the loading area. But with another 150 years of reserves at the site, the quarry is set to expand much further in terms of both area and depth so it is likely to retain its position as the lowest quarry on earth for some time to come.