Index USE OF VARIABLE SPEED DRIVES FOR ENERGY SAVING APPLICATIONS IN PULP & PAPER INDUSTRY BY : CHIRAG SHAH LARSEN & TOURBO LIMITED

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1 PAPERTECH 2005 AUTOMATION INDUSTRY ASSOCIATION USE OF VARIABLE SPEED DRIVES FOR ENERGY SAVING APPLICATIONS IN PULP & PAPER INDUSTRY BY : CHIRAG SHAH LARSEN & TOURBO LIMITED 11 th July, Why Energy Saving?? Most significant manufacturing cost. As high as 20% - 25% for Pulp & Paper Industry. 6 th Largest Energy Consumer Industry of India Ever Increasing Energy Cost Deficit of Electrical Energy Generation within the country Government Enforcement.. EC Act 2001 Social & Environmental reasons Lagging in Energy Consumption norms as compared to paper manufacturers in developed countries Source:Website-BEE 3 4 Electrical Energy Consumption Norms Vs I) Wood Based Mills Electrical Energy Consumption Norms Vs III) Recycled Fiber Based Norms (BEE) Bleached Newsprint Rayon (Pulp) Writing Printing (*) Newsprint (*) Board II) Agro Based Mills Norms (BEE) With Recovery Bleached Source:Website-BEE & Central Pulp & Paper Research Institute, Saharanpur 5 Without Recovery Norm (BEE) (*) With Deinking Source:Website-BEE & Central Pulp & Paper Research Institute, Saharanpur 6

2 7 Potential of Energy Conservation - India Iron & steel -- 10% Fertilizer -- 15% Cement -- 15% Aluminium -- 10% Textiles -- 25% Petro Chemicals -- 15% Refineries -- 10% Pulp & Paper -- 25% Source:Website-BEE 8 Culprits of Energy Wastage Major Reasons!!!!! Process Fans ID/FD/PA/SA, Cooling, Blowers,.. Process Pumps Feed Water, Chest, Fibre, Cleaner,. Compressors Over Sized Design - Design / Safety Margins Various Operating conditions Future Growth Plans Plants not operating at full capacity 9 10 Equation Centrifugal Load Energy Saving by reducing Speed Pressure a Flow 2 Flow a Pump / Fan Speed ( Speed) Output a Pressure x Flow p ( N / m 2 ) 1.0 p.u. p1 p2 P3 = (p1- p2) x Q1/ (? F x? M ) x 10-3 kw,? M = efficiency P3 x H kwhr where H = Annual run time of Pump/Fan in Hours B A SYSTEM CURVE WITH THROTTLING VALVE / DAMPER X P1 = p1 x Q1/? F x 10-3 kw,? F = Pump/Fan efficiency SYSTEM CURVE WITHOUT THROTTLING VALVE / DAMPER P2 = p2 x Q1/? F x b10-3 PUMP/FAN CURVE AT RATED SPEED kw Output a Speed Q1 Q2 1.0 p.u. 12 PUMP/FAN CURVE AT REDUCED SPEED Q ( m 3 / s )

3 13 Outcome Comparison of for Centrifugal Load System Energy saving possible by lowering the speed of the motor (instead of using Damper or Throttling Valve). The output is cube of the speed for Centrifugal Fan/Pump applications thus massive energy savings can be achieved. Variable Frequency Drives can be used to control the speed / torque of Induction 100 Consumption Damper control Energy saving Inverter control Supply Network VFD Driven Fan / Pump 0 Ideal flow or motor speed (%) 14 CASE STUDY I Why Energy Saving Energy saving in Process pump Process The process needs water during various stages. This water is supplied through two pumps, one of which is in operation and the other is on standby. The pumps are part of a Filtration plant. The system is shown below Pump # 1 Pump # 2 Pump Inlet Trials Trials were conducted using a 300kW AC drive in closed loop with PID control using output pressure as the controlled parameter. An energy meter and hour meter were used to record the consumed power and time. The results were as under: # 1 # 2 Changeover Switch VFD 300kW 17 18

4 19 With Star Delta Starter Initial readings on KWh = Hour meter = Readings = on KWh = Hour meter = KWh consumed ( KWh) = = Time period ( Hrs.) = = 567 Avg. Consu.(KW) = / = 164 With Drive connected : Output valve fully open, drive speed = 42 Hz Initial readings on KWh = Hour meter = Readings on KWh = Hour meter = consumed ( KWh) = = Time period ( Hrs.) = = Avg. Consu. (KW) = / = 99.4 % savings = / 164 = % Source : L&T 20 Case Study Energy Saving in Process Fans CASE STUDY II Energy saving in Fan Cooling Fan KW : 90kW Without VFD With VFD KW 68.3 KW 36.9 KW factor Air flow 52.6 m 3 /Sec 54.8m 3 /sec. Earlier in the system was run using a damper open 68%. After installation of VFD the Damper was kept fully open and the motor was run at a reduced speed. 21 % energy saving : ( / 68.3) * 100 = 46% 22 Source : L&T Benefits of VFD s Why Energy Saving 23 Massive energy savings can be achieved. Better Input Factor Inbuilt soft start feature provides smooth acceleration and limiting inrush current. Precise control of pressure and flow rate irrespective of supply fluctuations in the grid Reduced wear and tear of mechanical components Enhanced life of mechanical seals on equipment downstream to the pump due to pressure control Reduced wastage of resources e.g. water etc ROI generally between 6 Months to 2 Years 24

5 25 Popularity of VFD s - India How AIA Members can serve you More than 1,00,000 VFD s sold per year 77% of VFD s sold are for Energy Saving purpose VFD sales growing at CAGR of more than 24% AIA Members contributes to almost 58% of this Pulp & Paper Industry contributes only 2% of this Source : L&T Estimation Identification of Energy Saving Applications Supply VFD s from few Watts to Mega Watts ratings Slash your energy Bills & thus Increasing your profits Improved quality of process output Thus helping you to become more competitive globally 26 ENERGY SAVED IS ENERGY GENERATED ENERGY SAVING IS SERVICE TO NATION Q & A!! : MY SINCERE THANKS TO : - All PARTICIPANTS - AUTOMATION INDUSTRY ASSOCIATION - LARSEN & TOUBRO LIMITED