The future of kiln optimisation
Cemtech held its ninth webinar of the year this week, with an overview of how best to optimise the rotary cement kiln. The webinar consisted of three presentations providing the latest information on technologies including kiln burners and seals, a brand new drive system, plus a kiln and preheater upgrade case study. The technology in the webinar underlined how Europe was still a major force in the cement sector for leading product development.
thyssenKrupp Industrial Solutions
Stephan Pallmann, thyssenkrupp Industrial Solutions AG (TKIS), started with the essential function of the kiln drive and the company’s new POLGUIDE self-aligning kiln drive equipment. POLGUIDE is designed for kilns with two or more supports and has particular value for revamp projects on older kilns between 3000-6000tpd. POLGUIDE has the flexibility of being fitted with fixed or self-adjusting roller stations.
One of the first case study installations for this technology is in Germany, where TKIS applied POLGUIDE-2S to a 4.8m dia. x 68m kiln. Additional POLGUIDE projects have been completed in Bolivia, on a 3000tpd three-pier kiln, and in Tunisia on a 3500tpd three-pier kiln.
Another essential part of kiln performance is the kiln seal. Stephan introduced attendees to the polysius® Graphite Block kiln seal. The seal improves kiln stability and is energy efficient and capable of reducing CO2 emissions with lower heat consumption.
TKIS also highlighted the POLFLAME® second-generation burner, designed for combustion of alternative fuels and low-NOx operation. The POLFLAME range includes a variable nozzle burner and a multi-channel burner. “About 30-40 per cent of NOx is established in the sintering zone, but 60-70 per cent is produced in the calciner,” said Stephan. “By keeping NOx lower in the sintering zone this will reduce the amount of NOx formation in the calciner.”
HGH Systèms Infrarouges
The second speaker was Jean-François Boissou, HGH Systèmes Infrarouges, who spoke on how thermography can be a powerful kiln tool in supporting digital trends in the industry. HGH supplies Kilnscan to monitor the kiln shell, and Pyroscan as a thermography scanner for inside the kiln. Both systems are useful tools for maintenance and Pyroscan really comes into its own for process control. “Together they are valuable for finding optimum and cost-effective plant operation,” said Jean-François.
Jean-François explained how data interfaces of thermography products play a vital role in recording information at plant level. Digital interfaces and data export interfaces are the latest trends for getting the most information from Kilnscan and Pyroscan.
It is important to remember that between the process line and the digital world, it is the interface sensors that are the source of the main plant data.
“The drawback with images is that they use a lot of storage, ” he added. Plants need to focus on particular areas of interest to provide smart data, rather than recording everything.
Dal Engineering Group
The final presentation was given by Adnan Can, Dal Engineering Group. Adnan explained that Dal has a filter-to-filter pyroprocessing package for revamping kiln systems. The preheaters can be designed up to 6000tpd capacity, with 700tpd modular cyclone design for smaller capacity plants.
Dal’s advanced process control (APC) also provides software for optimising kiln performance. Furthermore, Dal’s Expert Suite provides safer operation, increased stability and higher reproducibility of performance.
Nuh Cimento case study
Adnan completed his presentation by highlighting the Nuh Cement project in Turkey, which has recently undergone a clinker capacity increase from 2800 to 3200tpd. The turnkey project was completed in just 35 days during one kiln shutdown and included modification of eight cyclones, a new kiln inlet seal, clinker cooler, tertiary airduct, removal of dust chamber, cooler vent fan and kiln feeding system. After the modernisation, Dal Engineering achieved a clinker production of 3400tpd, with specific heat consumption at 750kcal/kg clinker, ambient clinker temperature of 54.5˚C and a lower heat consumption of 24kWh/t clinker.
In a separate project Dal added APC to the plant a year ago. In just three months the project was completed with a single month on site to optimise the programme. The results saw production increased by four per cent, specific power reduced by two per cent and a 1.5 per cent decrease in specific heat consumption.
