SOMEVAM, a subsidiary of the Sebri group, has operated sand quarries in Oueslatia, Tunisia, serving the national construction market since 2001.
Following testing of material, the company saw the opportunity to diversify into the glass industry in North Africa and Europe and produce a range of supplementary products, including industrial sand and silica flour. The company also wanted to produce a 30-150-micron fraction that would make its offer unique in the region.
SOMEVAM sought an effective wet processing solution that would eliminate contaminants and offer variable cut points to increase the quality and commercial value of the end products.
Each day, SOMEVAM extracts 3,000 tonnes of sand. To handle such quantities efficiently while also adhering to stringent quality standards requires the most advanced, durable and sustainable processing equipment.
Together, the Tunisian company and CDE have developed a tailor-made wet processing solution to support SOMEVAM to achieve its commercial growth aspirations.
The design process, underpinned by CDE’s co-creation approach, allowed CDE engineers to work directly with the SOMEVAM team to develop a modular wet processing installation perfectly suited to the feed material (including a silica content of 99%) and the company’s production targets.
Habib Sebri, CEO of SOMEVAM, explains: “Before we got into glass sand, we operated the Oueslatia site for the production of building materials. However, it was clear that the material onsite presented an interesting commercial opportunity in the field of silica for flat glass applications such as windows, mirrors and flat glazing.”
Sebri says it was essential to invest in the right sand treatment equipment to guarantee the success of the project.
“After exhaustive research of the various options at our disposal, we chose a modular wet processing solution from CDE. The expertise of the company’s engineers and sales team, its investment in innovation and new technologies, and the quality of the materials used during the manufacturing process were the key determining factors in our decision.”
To guarantee precise control of sand cut points, SOMEVAM opted for a complete turnkey CDE solution. The CDE plant can treat up to 200 tonnes per hour of sand, producing 100 tonnes per hour of silica glass sand for the glass industry. It can also make a range of secondary products including fine silica sand for silica flour production, foundry sand, concrete sand and road base.
The installation features a combination of CDE equipment operating in perfect synergy; an M4500 primary wash plant to classify materials, five high-frequency Infinity Screens, four attrition cells, spiral separators, CDE’s Counter Flow Classification Unit (CFCU), a nano-cyclone, magnet, four EvoWash sand washing units and an AquaCycle water management solution. Combined, the system processes fine and coarse materials and eliminates contaminants to produce high-specification glass sand.
Since its launch in 2014, CDE’s M4500 has quickly become popular and is installed in plants around the world. This high-tech plant is compact, powerful, easy to use and economical.
CDE’s cyclone technology uses centrifugal force for classifying materials rather than gravity, which retains every grain of viable sand in the system. The design of the cyclone also makes it possible to establish a number of variable parameters to obtain unrivalled cut-point precision.
Attrition, spirals and magnetic separation processes are used to remove contaminants from the product and maximise the silica content.
Bassem Idriss, project manager for the Europe and MENA region at CDE, explains: “The M4500 demonstrates the effectiveness of CDE’s cyclone technology and the flexibility of our process and engineering teams, who have designed the process to produce very high-quality glass sand to meet SOMEVAM’s requirements.
“The hydrocyclones were built according to the specific needs of the client, based on analysis of the feed material carried out by CDE during the pre-project phase.
“The process water, loaded with undesirable fines, is removed at the level of the overflow of the cyclones while the treated sand enters the dewatering and stockpiling phase. With cutting points of incomparable precision, the products are treated according to the required standards and without risk of mixing.”
To produce a very clean sand product requires a very good supply of clean water. The new installation incorporates CDE’s cutting-edge water management system, the AquaCycle thickener with a capacity of 1500m³ per hour. Waste water from the plant is processed by the AquaCycle thickener which recovers up to 90% of the process water to be recirculated back into the washing plant, minimising the size and maintenance requirements of the settling ponds, which is particularly advantageous where the site is situated in Tunisia.
Idriss continues: “In Tunisia, a hot and dry country, it is important to consider the difficulties of accessing fresh water. It is essential not to waste a drop of water. CDE’s AquaCycle allows SOMEVAM to recycle process water in a closed circuit for immediate reuse in the system.
“The waste water, after passing through the deaeration chamber and after having been in contact with the flocculant injection, passes to the centre of the AquaCycle so that the flocculation process operates and acts on the sedimentation of the fines. The integrated flocculation unit allows precise dosing of premixed flocculant for effective decantation. A single motor drives the AquaCycle rake arms for optimal sludge treatment before disposal.”
The CDE installation for SOMEVAM transforms the feed material into five high-specification products with exceptional commercial value. It produces glass sand (150-650 microns) and related products, including oversized (3mm) ready to be used in water filtration systems, coarse sand (650 microns-3mm) ready to be ground to make flour silica, ultrafine (30-150 microns) for ceramics or other industries, and iron-rich sand that can be used in sports fields. With a typical moisture content of 12%, the materials are market-ready straight from the belts.
Sebri comments: “Our CDE solution has made a huge impact on the glass sand industry in Tunisia and in the North African market. It represents the most advanced technology available on the North African market and has enabled us to become ultra-competitive in an industry with extremely high-quality standards.
“Our glass sand is sold for the production of white glass, and the other fractions are sold for various industrial applications. Our quick return on investment was thanks to the power and efficiency of our CDE solution.
“We have succeeded in expanding our offer and positioning ourselves in new markets, which has strengthened SOMEVAM’s reputation with its customers for quality and consistency of service.”
CDE equipment is designed and manufactured to adapt to the circumstances of each unique site to maximise the quality and quantity of the materials produced. In the case of SOMEVAM’s siliceous site, the requirement was an exact solution to support the business to expand its operations adhering to stringent quality standards in the glass sand market.
In collaboration with the client, the CDE team designed a tailor-made installation capable of simultaneously producing five products of different particle sizes without the risk of mixing so as not to compromise their quality and consistency.
CDE engineers work with the company’s sustainability ethos in mind; to achieve a goal of zero waste and maximising water efficiency. CDE offers a range of advanced technology products with modular design features that can facilitate future upgrades to the existing system.
Every CDE project benefits from its customer-for-life model. It ensures transparent and effective communication from the beginning of the project until commissioning and unrivalled after-sales support.
Sebri concludes: “We are very satisfied with the value for money our CDE equipment has provided. We particularly appreciate the service we received. At the start of the project we visited CDE’s facilities in Northern Ireland and felt assured by the quality of the materials used and the expertise of its engineers, both in the design and in the manufacturing of our installation.
“CDE offers a complete service, from design to after-sales, managed at all stages of the project through a single point of contact and based on over 25 years of international experience and wet processing expertise. This was hugely important to us given the level of investment and the longevity of our operations.
“Mr. Idriss, our CDE project manager in Tunisia, as well as CDE’s engineers onsite, were present and attentive to all stages of the project, ensuring a smooth process. I can say without hesitation that CDE has revolutionised our operations.”
