JMP Engineering (Corporate)

Lime Kiln Optimization System

Overview

The Lime Kiln Optimization System (LKOS™) developed by Automation Applications Inc, LLC (AAI) optimizes lime quality and maximizes throughput and efficiency of the Kiln in manufacturing operations. Using the hardware and software tools found in a modern Distributed Control System, and the instrumentation typical of a Kiln, the LKOS provides the benefits of increased lime quality and reduced process energy consumption.

Features

  • Control-based on Btu heat balance through the kiln
  • Three zone “decoupled” control
  • Residual CaCO₃ stabilization
  • Complete process data monitoring, trending, and historical logging

With the LKOS, variability of residual CaCO₃ in re-burned lime is reduced, and energy used per pound of product is decreased overall. The ratio of fuel to product is constantly and automatically controlled providing a stable heat balance and further reduction in fuel usage.

With the kiln operating on optimized control, operating targets, which have traditionally included a “comfort zone”, are tightened. Stabilized hot and cold end temperatures minimize dust losses and reduce exit gas temperatures. Higher quality lime positively affects white liquor such that digesting is stabilized, liquor strength is increased, and evaporation costs are reduced.

The user interface to the Lime Kiln is improved such that functions requiring manual intervention are automated. Additionally, optimization of flame shape and precise control of the overall heat balance prevents overfiring in any section of the kiln. LKOS can be installed both on new kilns and as a retrofit to existing Lime Kilns. In cases where an existing control scheme has been replaced, Pulp Mill owners have typically realized the following benefits.

Benefits

  • Reduction in standard deviation of residual carbonate
  • Reduced fuel consumption
  • Overall lime kiln stability increase
  • Increased production capacity
  • Increased efficiency
  • Reduced emissions
  • Improved protection of process equipment
  • Complete operator acceptance of control system

Conclusion

AAI believes that competitive advantage can be gained by pulp and paper manufacturers through the proper application and use of today’s computer and control equipment.