Due to the scarce petroleum resources, large coal-to-liquids and gas-to-liquids plants (CTL and GTL) were created in South Africa for the production of fuels as well as basics of the chemical industry. The Sasol companyis market leader in this area. At the two large locations Sasolburg and Secunda, coal is exploited over a large area and partially highly explosion-prone substances are processed. A safe working environment and good monitoring of machines as well as personnel is absolutely essential for an effective operation. For this reason, we implemented our powerful TETRA mobile radio system for Sasol at both locations.
Coal mining and the processing in Secunda as well as gas processing in Sasolburg each consist of a complex sequence of different automated process steps. An error in one of these steps leads to an interruption of the processing chain and, as a result, to enormous losses. Our ACCESSNET®-T offers employees a communication system with high voice quality for safe and efficient work.
For the employees in the harsh operational environments, Sasol made high demands on the communication system. With our robust, customer-specific solution, we were able to meet the demands without compromise. Extensive redundancies of the system elements guarantee a trouble-free, continuous radio supply. The flexibility and technical performance, even at peak loads, are additional highlights of our extensive system.
Thanks to the multifunctional ACAPI interface, external applications can conveniently be connected to our TETRA mobile radio system. For the mobile radio network for Sasol, we collaborated with our partner Expert System Solutions (ESS) who provides a powerful SCADA system at the individual locations. This SCADA system transmits the information via SDS using our infrastructure.
Our Solution
One challenge during the integration was the arrangement of the base stations. The possible locations outside of the hazardous areas were precisely calculated to enable an optimal mobile radio coverage. As a result, a continuous mobile radio supply exists over the entire 4,000 km2 company complex in Secunda, including inside of buildings. Both locations feature several base stations that are outside of the company site. This allows reaching employees or the company’s own fire crew in emergency situations.
The mobile radio system at the larger of the two locations, Secunda, shows an enormous operational performance during peak loads: Up to 52,000 calls are made every day. In this case, 8,900 subscribers, 800 groups and 110 fleets are registered in Secunda. In the process, different call priorities guarantee an effective communication that is tailored to the respective situation. Based on the increasing communication demand, particularly during the annual maintenance period, we are continuously expanding and optimising the mobile radio system.
All types of different applications supplement the scope of functions of our flexible ACCESSNET-T IP system: Radio calls are recorded and played back using the TETRA voice recorder. For every recorded call, including the group calls, extensive information such as time stamp and subscriber information is being stored. The user-friendly interface and implemented search function enable users to quickly and easily call up previous connections. The AVL/GIS functions ensure an increased safety at the company site through the localization of handheld and vehicle radios.
Highlights of our solution
- Highly redundant design of all switching controller nodes and base stations
- Flexible expansion of the mobile radio system
- Effective frequency utilisation with full functionality at maximum network utilisation
- User-friendly voice-and-data recorder with extensive search functions
- Distributed switching functions in base stations and switching nodes
