State-of-the art conveying technology and silo design for the cement industry, Dry Cargo International (DCI), Novermber 2014

While cement is as vital a commodity to fast-growing economies as oil or steel with no other material being as versatile for building houses, roads and infrastructure, it is difficult to transport and potentially polluting if not stored and transported carefully,” says Paul van de Vyver, General Manager, DemcoTECH Engineering.

As a key supplier of bulk materials handling technologies and services to the cement manufacturing and related industries, South African based materials handling specialist DemcoTECH Engineering offers the global industry a complete solution for the storage and transportation of cement.

CONVEYOR DESIGN

As with all the commodity markets we serve, maintaining a clean environment is a priority in all the systems we design and supply to the cement industry,” notes van de Vyver. “As a result, we offer specialised conveying systems, such as troughed AeroConveyors™, pipe conveyors and pneumatic conveying systems, which, by providing a totally enclosed conveying environment, assist the client in complying with environmental and safety regulations.

“What makes the AeroConveyor™ system unusual is the fact that it uses the air-supported belt principle to convey bulk materials, with air being used in much the same way as for a hovercraft, i.e. as an air cushion as a means of transport, eliminating the requirement for idlers.”

Although similar to the conventional idler-supported conveyor system, a trough section is used as the structural support of the belt on an air cushion.

“Air, a natural resource is used successfully as a substitute for idlers, yielding substantial benefits, including an economical-to-construct-and-operate conveyor and one that has very few moving parts, thus requiring very little maintenance.”

DemcoTECH Engineering offers specialist expertise in pipe conveyors, having supplied this technology to a number of cement producers around the world. Besides secure handling of the material, pipe conveyors offer many other benefits, such as being environmentally friendly without the spillage problems associated with troughed conveyors. Pipe conveyors are able to negotiate relatively tight horizontal and vertical curves, which affords the opportunity to eliminate transfer points, reduce the overall length of the conveyor system and improve the plant footprint, and save total costs.

“The potential conveying distances and carrying capacity of pipe conveyors have improved significantly in recent years due to improved conveyor analysis capabilities and advances in component design, to the extent that pipe conveyors today offer clients a realistic alternative to conventional troughed conveyors,” highlights van de Vyver.

Pipe conveyors designed by DemcoTECH Engineering comprise both fabric and steel cord belting, have up to 2,250 tph conveying capacity and are up to 500 mm in diameter. “We have also engineered two-way pipe conveyors, multiple curve pipe conveyors and distributed drive pipe conveyors with excellent results,” says van de Vyver.

“A particular benefit of the DemcoTECH pipe conveyor is that these systems can be designed using a triangular tubular gantry fitted with a mobile maintenance trolley,” adds van de Vyver.

Two such travelling maintenance trolleys were designed by DemcoTECH Engineering for a cement producer, each equipped with maintenance power sockets. These maintenance trolleys had to negotiate an incline of up to 15° while carrying four personnel together with spares and tools.

DemcoTECH Engineering’s track record in supplying pneumatic systems for the cement industry includes a 150 tph pneumatic transport system to convey cement from a kiln to multiple storage silos, also at Nova Cimangola’s cement plant in Luanda.

“Working in conjunction with Claudius Peters in Germany, we provided a system with a conveying distance of over 300 m, following a tortuous route to fit into the existing plant and including seven discharge points into the existing silos.”

CEMENT SILO DESIGN

DemcoTECH Engineering offers the full suite of services and technologies for the design and construction of cement and clinker silos in partnership with Kantey & Templer Engineers. All equipment complies with environmental and safety requirements and typically includes airslides, flow-control gates, mobile road outloaders, fully-enclosed cement transport/conveying systems, and dust filters, which provide effective removal of dust from all the areas of dust generation.

DemcoTECH with Kantey & Templer completed the new 40,000 ton capacity, multi-discharge clinker silo at NPC Cimpor’s Simuma Plant in KwaZulu-Natal, South Africa on a turnkey basis.

“The Simuma Cement Plant is located in an environmentally sensitive area and the design ensures that dust emissions from the plant are controlled well below regulatory requirements,” says van de Vyver. “Dust extraction filters are included on the silo and at all the transfer points to ensure the dust emissions comply with the safety and health regulatory limits. ”

About DemcoTECH Engineering

DemcoTECH Engineering is a leading specialist in the bulk materials handling field, offering its clients a range of services from concept to full, turnkey project completion. DemcoTECH Engineering offers clients conveyor design through to turnkey supply and has completed the design and engineering of large import/export port facilities, gold plants, diamond tailings disposal systems, manganese storage and export facilities, sampling plants and a wide range of other projects including niche process plants.

Services include concept design, feasibility studies, detail design, engineering, procurement, expediting, construction and commissioning for a wide range of industries, including the power generation, cement, mining, metallurgy and manufacturing industries, as well as port facilities.

DemcoTECH Engineering offer a full range of materials handling products and solutions including troughed conveyors, pipe conveyors, air assisted AeroConveyors™, rail-mounted slewing stackers, pivot-boom conveyors and mobile conveyors.

Above left and right: 40,000 ton multi-discharge clinker silo project for NPC Cimpor’s Simuma Plant in KwaZulu-Natal, South Africa.