April 17-19th, 2012 International technical Symposium

Transcription

1 April 17-19th, 2012 International technical Symposium Costs Saving Diagnostic Systems Applications Luca Canali, Diagnostic Systems Development Leader

2 The energy benefits of removing as much water prior the dryier section is self-evident On-line measurements on paper machine allows quick control system response Energy Saving Impacts on Forming Section A B X5 X5

3 Energy Saving Impacts on Forming Section FiberScanFIX on-line sensors allows a reduction in vacuum box load and drive load. Why? On paper machine there is often an excessive vacuum level or vacuum curve are not optmized

4 How to Calculate Energy Costs/Saving in Forming Section Electricity cost in forming section is approx* 50 KWh/adt (Air Dryed Tons) If energy cost is 0,13 /KWh Energy cost per Ton of paper is 6,5 *Depending on forming section configuration

5 A Pratical Electricity Cost Calculation Machine speed: m/min Grade: copy 80 gr/m2 Width: 4,80 meters ton/year: t/y Electricity cost = t x6,5 /t= Energy saving 10% = saving *Depending on forming section configuration

6 How to Save 10% Energy? Vacuum setup 1 Vacuum setup

7 Example: How to Save 10% Energy

8 ROI (Return On Investment) FiberScanFIX Return of investment can be very fast (from 6 to 12 months according to the machine production t/year) only assuming electricity cost saving

9 % dryness after the top f 21 20,8 20,6 20,4 20, ,8 19,6 19,4 19, ,5 1 1,5 2 2,5 3 3,5 kg/t Poli. (8694) Poli. (8591) ROI (Return On Investment) Possible additional saving: Chemical additives tuning 40 Evaporation rate (kg/m2) X Af ter X Bef ore 0 0,0 0,2 0,4 0,6 0,8 1,0 1,2 1,4 1,6 1,8 2,0 2,2 2,4 2,6 2,8 3,0 3,2 3,4 3,6 3,8 4,0 kg Steam/kg H2O Dryer section steam consumption Fig.6 - Comparative diagram measuring dry-end efficiency among machines with similar production. Driving energy Refining optimization Vaccuum energy adjustment

10 FiberScanFIX Target Positions Measurements before Top unit to optimize dewatering Measurements before ply bonding to optimize paper couch adhesion Measurement at couch roll to know dryness before entering press section

11 FiberScanFIX Target Positions Before top dewatering unit Dewatering control Formation monitoring Refining control Chemical dosage tuning

12 FiberScanFIX Target Positions Before dandy roll Dewatering control Marking control Constant paper quality Vacuum saving

13 FiberScanFIX Target Positions Before Couch roll Vacuum saving Drive load saving Dryness optimization

14 FiberScanFIX Target Positions Gap formers Vacuum saving Dewatering monitor Dryness optimization

15 FiberScanFIX Target Positions Before Bonding point + couch roll Energy saving Dryness optimization Vacuum reduction

16 What is FFT Analysis? FFT (Fast Fourier Transform) is an efficient alghoritm that decomposes a sequence of values into components of different frequencies Frequency, is the number of vibrations in a certain time, e.g. cycles per second, when the unit Hz (Hertz) is used or cycles per minute (cpm).

17 OptiWave FFT Analysis Frequency, is the number of vibrations in a certain time, e.g. cycles per second, when the unit Hz (Hertz) is used or cycles per minute (cpm). Amplitude, in the case of pressure pulsations is the magnitude of the pulsations.

18 Which Are The Variables? Screen rotating elements Piping design Mechanical vibration Pump drive System design (resonant frequencies) Headbox feed pumps Vacuum systems

19 db FFT Analysis Example Amplitude: decibel Gain: decibel Mass variations msec fft Time: mm/second Frequency: Hertz

20 Frequencies Troubleshooting Range Stock pulsation can occur in a range from 0 to 150 Hz. A mass pulsation is often accompained by multiple frequencies (harmonic freq.) Main frequency Harmonic frequency

21 Search Tips Find the frequency with the highest amplitude (15-20dB or well above noise) Calculate wich frequency is a common denominator of the main frequency and common of harmonic peak as well Main : 48 Hz Harmonics: Main frequency 12 Hz is common Harmonic frequency

22 Stock Pulsation Examples Peaks* Prob. cause Harmonics Example From 0 to 1 Hz From 1 to 5 Hz Vacuum pulsation No harmonics 0,2 Hz Breast roll shaker Double and half 2,5 Hz- 5 Hz-1,25 Hz From 8 to 15 Hz Pumps, feeding pumps,epurator X3, x5, x7, depending on the number of blades 12,2 24,4-36,6 Hz ( in case of 3 blades) From 10 to 20 Hz Feeding pumps, epurator X3, x5, x7, depending on the number of blades 14,4-72 Hz From 10 to 50 Hz Structural vibration, resonance Depending on vibration entity

23 Basis Weight Barring vs FiberScanONE FFT MD

24 Basis Weight Barring vs FiberScanONE FFT

25 What is a 3D Maps? 3D map is a three dimensional picture of the moisture or permeability variations in the felt. A colour scale shows different water/permeability level

26 Why 3D Maps on Felt? 3D maps better shows CD or MD irregularity compare to the standard view. A colour scale shows different water/permeability level

27 Why 3D Maps on Felt? CMD scanning in reality is a combination of CD and MD variation. It is well known that it is difficult to separate the effect of CD variation from those in MD direction.

28 A 3D map can reveal CD stripes and MD barring that are not visible on std views Std view Why 3D Maps on Felt? 3D view MD Higher Permeability bands Felt barring

29 Case 1: Roll vibration Troubleshooting MD barring Periodical variation at 12,56 Hz ( wave lengh 1,48 m ).

30 Troubleshooting Case 2: HP needle jets plugged CD stripes

31 Troubleshooting Case 3: a mix of roll vibrations and HP needle jets marks HP shower pattern (not periodical) Roll vibrations