New technologies are making cost-efficient cooler upgrades a reality for today’s cement producers.
How often is the cooler a bottleneck in clinker production? It’s a common challenge for most cement producers in an industry that is highly energy intensive and with greater need to optimise costs and increase productivity.
In the current economic conditions, cement plant owners are looking for productivity enhancement, cost-efficient solutions and faster payback. Increasingly, retrofits and upgrades are seen as the best choice, and for coolers in particular, there are compelling reasons for retrofitting and upgrading.Relieving the pressure
In their coolers, cement producers can face any number of operational bottlenecks, adding to the general challenge of maintenance and operational complexity. These include inlet build-up, red river, uneven air distribution, reduced availability, dusty clinker, poor flexibility, reduced thermal efficiency, increased losses, increased power, and insufficient heat input to the WHRS boiler.
All these factors create disturbances in the pyro processing systems, ultimately to the detriment of the plant’s commercial performance. Retrofitting a cooler with the latest available technologies is becoming increasingly attractive to producers as way to improve energy efficiency and availability of the pyro processing system. New generation clinker coolers
FLSmidth has a proven legacy of applying innovative technologies to achieve energy-efficient pyro processing solutions. The FLSmidth Cross-Bar? cooler makes use of the company’s advanced clinker cooling technology and has been implemented in more than 350 cement plants around the world, helping them to eliminate bottlenecks in production and improve the overall efficiency of the pyro processing system. FLSmidth is highly experienced in implementing in in-box, partial and complete cooler replacement solutions.
The benefits are due to several specific technologies and innovations, as discussed below. Consistently high thermal efficiency: Unlike other cooler designs, the FLSmidth Cross-Bar? cooler separates the clinker conveying and air distribution systems.
Reciprocating bars fitted above the stationary air distribution system effectively convey, mix, shear and preparing the clinker for efficient exposure to the cooling air. A further benefit to this separation is that gradual wear of the bars has no effect on the kiln and cooler operation, and thermal efficiency stays high throughout the lifetime of the cooler.
The highest thermal efficiency is provided by the cooler’s Mechanical Flow Regulator (MFR) technology, which limits the airflow to a grate plate only if required. This delivers the desired level of air distribution, which is key to good operational performance amidst varying clinker granulometry. Even at a reduced air load, good air distribution can be achieved by adjusting the MFR.Maximising reliability and availability: With increased stickiness of the clinker due to optimised fuel and raw mix chemistry, the ABCTM Inlet is an ideal choice to ensure the highest cooler availability.
The process air is controlled by MFR technology. In the grate, air blasting is grouped in zones for effective removal of snowman and agglomerates.
Another factor contributing to the equal distribution of clinker – helping to prevent red river – is the FLSmidth Cross-Bar? cooler’s flexibility. This allows the stroke length across each lane to be varied. Fast, low-cost installation: With the highly flexible modular design, the FLSmidth Cross-Bar? cooler is designed not only for new coolers, but also as upgrades inside any existing cooler casing. The units are preassembled and workshop-tested to ensure high quality. A low total installed cost is achieved by several salient features like Horizontal construction, Cooler & HRB Modules pre-assembly, No under grate spillage or conveying system.Low, easy and predictable maintenance: The FLSmidth Cross-Bar? cooler has few wear parts, meaning easy and economical maintenance. The bars and U-profiles are easily accessible from the over-grate area. During operation, a protective layer of clinker is maintained between the air distribution plates and the movable bars, which ensures a long lifetime for the air distribution plates. Experience has shown that the maintenance of the coolers is highly predictable and simple to perform during a typical kiln overhaul.
Hot air recirculation and maximising waste heat recovery: A special feature of the FLSmidth Cross-Bar? cooler is its ability to recirculate hot air and maximise heat recovery from mid-air for power generation. Its hydraulic cylinders can be relocated such that hot air recirculation is made available to the compartments as necessary to improve mid-air temperature and volume. More importantly, maximised heat recovery is feasible without sacrificing recuperation efficiency of cooler.Raising the performance bar
An innovation of FLSmidth, this principle of continuous airflow regulation helps optimise heat recuperation and distribution of air throughout the entire cooler, enabling fuel savings and more effective cooling. FLSmidth is committed to innovation and product development in an effort to provide the greatest value to cement producers. FLSmidth Cross-Bar? cooler is ideal choice for either new cooler or retrofit solution.FLSmidth Cross-Bar? cooler benefits
- Consistent thermal efficiency
- High reliability/availability
- Fast and low cost construction/Modular construction
- Low, easy and predictable maintenance
- Hot air recirculation/Maximised waste heat recovery
ABCTM Inlet benefits
- No snowman
- Increased availability
- High secondary/tertiary air temperature
- Reduced wear on cooler parts
- Better operational control
- Good clinker distribution
Customer benefits
- Maximum availability
- Minimum maintenance
- Sustained performance
- Maximised WHR power generation
- Faster payback of investment
- Low total cost of ownership
Author: G Renga Prasad, Product Line Manager-Pyro, FLSmidth.
(Communication by the management of the company)