ENERGY SAVING OPPORTUNITIES

 Dear Sir,

Wish you a very good morning , I am sharing THIS MATERIAL ENERGY SAVING OPPORTUNITIES & Case studies,  if we do case study in our plant , it  will be beneficial for us  to delegate the work through process and project student.1.00 Case Study: Reduction in steam for effluent stripping
2.00 Case Study: DM Water Pumping
3.00 Case Study: Boiler FD fanspeed control
4.00 Case Study: Boiler Feed Pump of Power Plant
5.00 Case Study: Heat recovery from CBD


Methodology & Scope of Baseline Audit 
•Subsystems in Fertiliser Plant
–Primary Reformer ( radiation & convection sections)
–Secondary reformer ( incl. WHB)
–CO2 removal system
–Synthesis loop
–Refrigeration system
–Urea synthesis reactor (incl. Ammonia pumps, CO2 compressors etc.)
–MP & LP decomposers
–Concentrators
–Granulation

–Water supply system ( from raw water to DM water, make up water etc.)
–Compressed air system
•Find out major energy consuming equipments in each sub-system
–Investigate the technology
–List out critical parameters which affect the efficiency and energy consumption
–Operating vs. Designed value
ENERGY SAVING OPPORTUNITIES
•Reduce Primary Reformer duty by reforming at lower temperature in Pre-Reformer. This can save about 0.15 Gcal/T with a payback period of 2-3 years.
•More efficient combustion by reducing excess air.
•Insulation / refractory for Furnaces, equipments and piping.
•More Heat recovery from flue gases, by additional coils and increasing size of existing coils. Additional BFW coils, combustion air heaters in convection zone can be done.
Supply Compression Energy directly by Gas Turbine and exhaust to HRSG or Reformer Furnace. Gain from more efficient power availability for compression.
•Use of Vapor Absorption for cooling GT / Compressor suction.
•Power Recovery Unit for High pressure gases letdown. Turbo expanders can reduce Fuel NG pressure from 40 bar to 10 bar and recover mechanical power. For 10000 Nm3/h NG consumption, about 400 kW can be generated. Payback period of more than 6 years.
•Hydraulic Turbine for utilizing pressure energy wasted during let down.

Case Study: Reduce water leakage in the fire water system
•The fire water pump was delivering a flow of 60 m3/h. 
•The pump input power during this isolated condition was about 89 kW, with a pump efficiency of 18% only. 
•We had taken trials with the help of safety & fire dept and technical services dept to identify the source of this 60 m3/h leakage of fire water. The team has identified leakages of 30 m3/h at Bagging house and SPG & offsites area. Thus reduction of 30 m3/h in leakage was arrested during the audit itself.
•Energy Saving = = 243600 kWh/year
•Cost saving = Rs. 4.5 lakhs/year
1.00 Case Study: Reduction in steam for effluent stripping
•Presently the ammoniacal and non-ammoniacal effluent is mixed. Significant amount of ammoniacal effluent from ammonia-1 from Syngas compressor intercooler mixes with other effluent, resulting in prolonged stripper operation and about 5 to 6 tons per hour of LP steam
•Stop ammonia mixing in intercooler and provide separate ammoniacal effluent stream from non ammoniacal effluent.
•Separate ammoniacal effluent collection pits are made and intercooler tubes have been replaced to arrest ammoniacal effluent.
•Annual cost saving potential of Rs 72.0 Lakhs/year
2.00 Case Study: DM Water Pumping
•DM water from DM Water Plant is sent to tanks in Ammonia-1 & II and then pumped from the tank to deaerator by separate pumps. Total power consumption of 2 nos pumps is 170 kW.

•DM water can be sent directly from DM water header to deaerator through control valve; a pump bypass line already exists as per original design (this arrangement is already operational in Power Plant)

•Annual cost saving potential is about Rs 25.0 lakhs, with an investment of Rs 5.0 lakhs
3.00 Case Study: Boiler FD fanspeed control
•Input power to motor driven FD fan was 260 kW. System efficiency (including fan + damper losses) is only 14.3%
•Reduce steam turbine speed and increase damper opening & automate control to move damper to preset position in case of changeover to electric motor drive
•Saving potential 69.7 lakhs/year
4.00 Case Study: Boiler Feed Pump of Power Plant
•Boiler feed pump driven by 1220 kW motor and standby pump of steam turbine driven.
•Operating pressure (observed during energy audit for few days) was 150 kg/cm2g while the drum pressure is 120 kg/cm2g
•Reduce the discharge pressure to 130 kg/cm2g by reducing speed of turbine and reducing stages of motor driven pump.
•Cost saving potential of 34.85 lakhs/year with an investment of Rs 60.0 lakhs 
5.00 Case Study: Heat recovery from CBD
•Presently about 2.1 m3/h of CBD is taken out from service boiler & HRSGs, which is flashed in drum. The condensate is cooled and discharged
•Install NG preheater from 30 C to above 80 C, by using this condensate, while reducing its temperature from 150 C to 60 C. •About 10.8 m3/h of NG saving realised. i.e. Rs 5.1 lakhs, with an investment of Rs 7.0 lakhs