Monday, December 18, 2017

Energy Conservation Tips on Cement Industry Print


Fuel:

  • Due to frequent variations in the quality of coal, inadequate supplies and transportation bottlenecks go for substitute fuels like, lignite, rice-husk, petroleum coke etc.
  • Use alternate fuels such as natural gas and pet coke.
  • Use industrial and agricultural combustible wastes as supplementary fuel.

 

Power Supply:

  • For uninterrupted power supply have your own captive power plant.

 

Operational Measures:

  • Use improved insulating bricks/blocks in kiln and preheaters.
  • Rationalise compressed air utilization.
  • Use energy efficient equipment
    • High efficiency fans
    • Improved Ball Mill internals
  • Carry out Heat and gas balance
  • Recover waste heat of preheater and use for cogeneration of power.
  • Increase utilization of waste products generated by other industries(substitution like use of fly ash and petroleum coke, the by products of thermal power and refinery industry respectively)
  • Install fly ash handling & feeding system.
  • Reduce energy consumption in manufacturing at each stage & monitor energy performance of the plant.
  • Prevent idle running of equipment by providing interlooking arrangement and operating with PLC system. Generate daily report on idle running of equipment, also in terms of monetary losses.
  • Eliminate ingress of false air into the kiln, cooler, coal mill, cement mill and raw mill circuits by plugging leaks.
  • Optimise raw mix
  • Use low ash coal
  • Adopt preventive maintenance approach
  • Repair steam leaks
  • Reinforce heat insulation
  • Establish efficient management information system for identifying various important parameters for efficient operation of the equipment and taking timely remedial measures.
  • Regularly monitor and calibrate flow meters.
  • Minimise waste by installing efficient dust collector equipment.
  • Modify the equipment to recover heat from the preheater and cooler in the process of cement making and effective use of industrial waste.
  • Use exhaust gas from kiln to dry raw material and coal etc.
  • Carry out energy audits.
  • Before improving a process, activities of good housekeeping and equipment improvement should be applied to promote energy conservation.
  • Avoid extra fine grinding of product to prevent wastage of power since it does not enhance long term strength.

 

Air Compressor:

  • Reduce compressed air pressure from 8 Kg/Cm2 to 7.0 Kg/Cm2 where ever possible to conserve energy, when required pressure at usage point is 6.0 Kg/Cm2
  • Stop use of compressed air for floor cleaning.
  • Check for compressed air leakage and arrest it.
  • Switch off one compressor if requirement can be met by balance operating compressors.

 

DG Sets Operation and Maintenance:

  • Improve SFC of the DG sets
  • DG sets flue gas temperature is more than 4500C install waste heat recovery boilers on DG sets to generate additional power & pre heat fuel oil
  • Improve specific electricity generation by loading in excess of 60% and upto 80%

 

Motors:

  • Replace underloaded / overloaded motors with proper size motors. Replace the motors with energy efficiency motors.
  • Prevent idle operation of the motors

 

Transformer:

  • If possible switch off one transformer running under loaded in parallel. Maintain all transformers at a loading of 70 to 80 % of rated capacity to minimize loss component (no load losses).
  • Try to have separate transformer for lighting where voltage can be kept low.

 

Power Factor :

  • Improve power factor by regular checking of current of all the capacitors and their timely replacement.
  • Install Automatic power factor correction device to have power factor of 0.99 to 1.00

 

Lighting :

  • Replace 40W Tube light by slim 28W Tube light and electromagnetic choke with electronic choke.
  • Replace 400 Watt Mercury Vapour lamps with 250 Watt sodium vapour lamps or 250 W metal hallide lamps.
  • Replace 250 Watt Mercury Vapour lamps with 150 Watt sodium vapour lamps or 150 W metal hallide lamps.
  • Provide more transparent sheet instead of asbestos sheets to use natural light.
  • Install energy saver for reducing the lighting load.
  • Prevent unnecessary lighting of the electric lamps.
  • Rationalize lighting in identified areas i.e remove excess lighting in identified areas. Also relocate lighting, if necessary.