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Port Elizabeth-based company Glendore Sand was established in 1979 and has since become the largest specialist supplier of sand in the Eastern Cape.
"Sand generally is of a very poor quality in the Eastern Cape, with natural river sand being in very short supply," Glendore Sand owner Desmond Eales tells Engineering News.
"We make use of dune sand which we ‘doctor', so as to produce sand of a suitable quality for use in mortar and plaster," he adds.
The doctoring involves the adding of a plasticiser, an air-entrainer, which the company manufactures itself, and lime, which reduces water demand and ensures that the sand conforms to SABS requirements in all respects, except for grading.
The building, plaster and concrete sand which the company sells, are screened to remove any organic matter, shells and stone.
The chemicals and lime are then added to the sand during the same process but after the screening has occurred.
In 2002, Glendore Sand approached Nquru Harbour Contractors a with proposal to screen dune sand onsite as a filler sand for the concrete which was required for the quay walls, and the dolosse plant for the Port of Ngqura.
After negotiations, the company was appointed subcontractor for screening the sand and delivering it to both batch plants.
Eales says that the question is often put forward whether there is too much salt in sand which is near to the sea.
"Few people realise that plants begin to grow within five to ten metres of the high-water mark as the salt content of the sand is already diminished.
"In the dunes where we mined, the salt content had long since leached out as they were more than 200 m from the high-water mark," he explains.
After rigorous testing this was proved and, after experimenting with various mix designs, a mix which required dune sand as a filler was settled on.
A new 8 5 4 powerscreen with stockpile conveyor was bought for this purpose from ELB Equipment and the operation started in May 2003.
"This proved to be a good choice of machine and, apart from routine maintenance, and a few minor hitches, excellent service was enjoyed from it throughout the contract," states Eales.
The contract ended last month with about 200 000 m3 of sand having been screened during the contract.
During the last five weeks the company worked on a 24-hour shift so as to enable the client to stockpile 26 000 m3 of sand for the completion of the contract.
This was necessary as the site had to be vacated so as to allow the civil side to complete the site work.
There were a few challenges that Glendore Sand had to overcome, with the main problem resulting from the stockpile areas.
"The stockpile areas were very limited because of space constraints, and the pressure to produce each day was always there as only about two days of sand requirements were available in the stockpile," says Eales.
"When a problem arose, we only had a maximum of 24 hours to be back in production, otherwise the batch plants would run out of sand." Eales feels that the contract was a success due, in part, to the professional approach of the client and in particular its batch plant manager, Lucas Louw. "In retrospect, it was certainly an interesting contract which had its moments and will stand us in good stead for our participation in the Coega Industrial Development Zone (IDZ)." The plant is being relocated to Glendore Sand's Sonop quarry, near the Coega IDZ, which is operated by Sunshine Coast Quarries, an affiliated company.
The company has also been involved in a number of projects within the IDZ and is negotiating more contracts.
"We supplied the building and plaster sand for the new Coega village, which was completed about 18 months ago, as well as the concrete sand for the new Neptune road interchange," says Eales.
"At present, we are supplying sand for bedding-and-filling purposes for services being installed in Zone 1 and Zone 2 of the IDZ; we have also supplied a large amount of sand for other infrastructure and services in the IDZ," he adds.
Currently, Glendore Sand is negotiating with Sander International South Africa (Sirsa), the first international investor in the IDZ, to supply the building and plaster sand for its site.
There are many more projects that the company hopes to get involved in but, due to the slow pace at which the development within the IDZ is moving, the company has to be patient.
The tender for the Coega Development Corporation's new office complex is expected to go out in July and Glendore Sands will await this.
"We feel we are well poised to cater for the sand requirements of the IDZ as well as the infrastructure and other facilities in the new harbour precincts.
"The slow pace at which the IDZ is taking off is a concern, but we are confident that it is going to take place. All indications are that things are starting to move forward.
"We are looking forward to the challenges that lie ahead," concludes Eales.
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