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Cypress Bend Bleach Plant July 2013 Report Envoy Development, LLC Slide 2 Review of June Report This past month costs have been lower than average May 8 to Jun 5: $35.34 Long-term Avg: $37.63 Costs were above average the month before April 5 to May 7: $38.55 #4 BSW CONDUCTIVITY: 15BSW4CO.ND This conductivity correlates some with cost, r2=0.18. Note the recent spike with costs corresponds with a spike in conductivity. In this model, a decrease in conductivity of 70, would decrease costs by $0.78. Also, note conductivity is not soda loss; the consistency of the mat is not considered. E2 STM MXR NAOH FLOW CTL: 16FIC46.OP Same profile as E1 caustic; both valves are swinging a lot, perhaps due to varying line pressure. 2ND CLO2 (D2) CONDUCTIVIT: 16D2COND.UC Conductivity was at historic lows in April, though they have recently increased to average values. There is a correlation with overall costs. Note the quartile chart shows conductivities from 1000 to 700 (which was seen from April to May) can reduce costs by $38.19-$36.31=$1.89 FILTER FEED PRESSURE CON: 34PC345.PV What is this? Costs fell when this increased substantially. 1ST CLO2 TOWER pH CNTL: 16PHC42D.PV pH increased when costs fell VAT DIL TO CL2 WASHER: 16FIC21.OP OP is at historical highs; normally correlates with better drainage/washing pH - D2 STAGE UPFLOW TUBE: 16PHC056.PV pH has been at historical highs SALTCAKE SLURRY PH: 34AC375.OP Decreasing since Feb and correlates some with overall costs. Is this used for pH control in the first stage? Slide 3 Total Envoy Cost This past month costs have been much lower than average Jun 7 to Jul 7: $30.49 Long-term Avg: $36.63 Costs were below average the month before, but this was investigated in June report May 8 to Jun 6: $35.31 In this report we compare the purple to the green periods which is a cost difference of $4.82, and is significant About $3.11 of this is due to no recorded caustic flow in the E2 stage. Slide 4 Summary This past month costs have been much lower than average Jun 7 to Jul 7: $30.49 Long-term Avg: $36.63 Most of the cost difference is due to E2 caustic flow not showing a flow; this is $3.11/ton Kappa was not significantly different We put a lot of effort into trying to identify if production rate is lower; if production was overstated, it would have an impact on stated costs Our flow model uses flow vs valve position, and detected a higher than expected flow after May 23. However, we ran a correlation between bleach plant rate and a number of amps, speeds, level control valves, etc, and they all have very good correlations. Therefore, we believe production rate is probably correct. D1 pH continues to be above average, and costs continue to be lower in that stage. We recommend you continue this practice. Steam mixer valve positions are running lower, but they didnt decrease at the same time. We believe the upstream washers are draining better, resulting in a dryer mat; since E filtrate is hotter than ClO2 filtrate, less steam is required to achieve the temperature setpoint. Slide 5 Maintenance Issues E2 STM MXR NAOH FLOW CTL: 16FIC46.OP Flow decreased to zero while OP maxed out. Is caustic being used here or is it shut off? If it is in use, when will this meter be fixed? COOL TOWER TEMP CONTROL: 34TC428.PV Temp is higher and swinging with OP at zero INCHES H2O IN ACCUMLTR: 14PIC86.PV Pressure is increasing and swinging with a decrease in OP FILTER FEED PRESSURE CON: 34PC345.PV Decrease to average values in June, though OP was relatively unchanged. Was a calibration done here? Notice the OP is increasing slightly with time Slide 6 Observations pH - D2 STAGE UPFLOW TUBE: 16PHC056.PV Costs have been lower since this pH increased 50%; r2=0.37 which is fairly high for 256 data points 1ST CLO2 VAT DIL FLO CTL: 16FIC43.OP Dilution has increased with lower costs suggesting better drainage 1ST CLO2 WSHR VAT LVL CT: 16LIC49.PV Vat level has been decreasing with costs, usually suggesting better drainage as well EO STEAM MIX TEMP CONTRL: 16TIC24 PV vs OP Note that the PV has been 180, but the valve output is much lower. Either the steam pressure is higher (cant find a tag for that) or the first ClO2 stage washer is more efficient (dryer mat); we can rule out the stated production rate is inaccurate. E2 STEAM MIX TEMP CONTROL: 16TIC47 PV vs OP The PV has remained around 170, yet the OP is falling. Again, this would happened if the mat was dryer off the washer deck or if the steam pressure was higher. In the case of pressure, we would expect them to drop on both E stages at the same time but that is not what we see. CLO2 TO 1ST CLO2 STG: 16FIC42.PV There is a correlation between D1 ClO2 and EO steam mix temp OP with r2=0.36 Slide 7 Recent Changes STEAM PER DIG HW: STDGHW.PV Steam use has been decreasing since May 26 ACCUM PRIMARY PRESS - VL: 14OP86.PV Decreasing with lower costs NCG VALVE OUTPUT: 14PIC87B.OP This increased, but it was essentially no change: it is maxed out. FILTRATE TO KNOT DRAINER: 15OP177.PV Pressure has been increasing since March SR Defoamer usage quality calc: 15sr_lbs.calc Defoamer usage has been lower with lower costs #1 BSW Downleg Vacuum: 15vi002c.pv Vacuum has been decreasing since Feb. Any air leaks? GEN PRES TREND POINT: 34OP343.PV Currently at historic high 15% Caustic Density: 35DIC020.PV Continues to decrease FLOW - 50% CAUSTIC TO WL: 35FC040.OP Currently at historic high Brownside HW Prod Bias: Brncons.hwbias Currently at historic high but did not change when costs fell Slide 8 E2 STM MXR NAOH FLOW CTL: 16FIC46.OP Flow decreased to zero while OP maxed out. Is caustic being used here or is it shut off? If it is in use, when will this meter be fixed? Slide 9 COOL TOWER TEMP CONTROL: 34TC428.PV Temp is higher and swinging with OP at zero PV OP Slide 10 INCHES H2O IN ACCUMLTR: 14PIC86.PV Pressure is increasing and swinging with a decrease in OP PV OP Slide 11 FILTER FEED PRESSURE CON: 34PC345.PV Decrease to average values in June, though OP was relatively unchanged. Was a calibration done here? Notice the OP is increasing slightly with time PV OP Slide 12 KPI Overview When comparing the higher costs seen in May to the lower costs of June Blow Kappa increased 2.1%, continues to have poor correlation to overall cost #4 BSW Conductivity increased by 7.7% and correlation to cost has weakened Brightness has decreased by 0.3% and is significant Tag NameTag Description June 7 to July 7 Low Cost June 6 to May 8Diff of MeansPct of Means Z-Score Null Hypothesis Significant 95% Total Envoy Cost 30.4935.314.8213.6%7.55yes 16KI151.PV Kappa Before D0 Stage12.6212.560.060.5%0.43no Kappa_avg_blow. pv Blow Kappa Average14.5214.220.302.1%3.76yes BLCHPROD.PV BLEACH PRODUCTION RATE898.41882.8815.531.8%0.86no 16D2HWBR.ITE FINAL (D2) HW PULP BRITE87.6687.960.300.3%2.41yes 15BSW3CO.ND #3 BSW CONDUCTIVITY5754.255619.41134.852.4%0.65no 15BSW4CO.ND #4 BSW CONDUCTIVITY983.44913.1070.337.7%2.38yes CostAboveTarget Cost above (+) or below (-) model-14.20-8.535.67-66.5%8.88yes Slide 13 Kappa Before D0 Stage: 16KI151.PV Remains at average values Slide 14 Blow Kappa Average: Kappa_avg_blow.pv Average Kappa increased 0.3 and is currently at historic highs Slide 15 BLEACH PRODUCTION RATE: BLCHPROD.PV Remains stable Slide 16 FINAL (D2) HW PULP BRITE: 16D2HWBR.ITE Data without fliers (values>86). Brightness dropped to historic lows on May 28 correlating some with overall costs. Was this deliberate? Slide 17 #3 BSW CONDUCTIVITY: 15BSW3CO.ND Continues to be above average; however poor correlation to cost Slide 18 #4 BSW CONDUCTIVITY: 15BSW4CO.ND Recently values increased and correlation to cost is weaker (r2=0.02 vs 0.18 last month) Slide 19 Cost above (+) or below (-) model: CostAboveTarget Error is increasing, which is due to the E2 cost dropping to zero shown later Slide 20 Cost Per Stage When comparing the higher costs seen in May to the lower costs of June, every stage saw a reduction in costs except D0, which was not a significant increase. E1 decreased by $0.61 (-7.2%) D1 decreased by $0.84 (-9.0%) E2 decreased by $3.11 (-105%), this dropped to zero on June 6 and flatlined. This is the reason for the very low costs this month D2 decreased by $0.33 (17.9%) Tag Name June 7 to July 7 Low Cost June 6 to May 8Diff of MeansPct of Means Z-Score Null Hypothesis Significant 95% D0 Cost12.8512.780.070.5%0.23no E1 Cost7.868.470.617.2%1.98yes D1 Cost8.469.300.849.0%5.20yes E2 Cost-0.172.933.11105.8%35.46yes D2 Cost1.501.830.3317.9%4.67yes Total Envoy Cost30.4935.314.8213.6%7.55yes Slide 21 D0 Cost: D0 Cost Increased slightly in June, but not significant Slide 22 E1 Cost: E1 Cost At historic lows Slide 23 D1 Cost: D1 Cost At historic lows Slide 24 E2 Cost: E2 Cost E2 NaOH flow dropped to zero on June 6 accounting for the costs dropping to zero Slide 25 D2 Cost: D2 Cost At historic lows Slide 26 Flow Meter Evaluation Slide 27 BL STOCK CNTRL VLVE OUTPUT: 16FIC102.OP Multiple curves, but the OP has been fairly consistent since Feb 4 Slide 28 BL STOCK CNTRL VLVE OUTPUT: 16FIC102.OP Data since March showing a decrease in correlation. Trend is looking non-linear, meaning that at valve positions >60% the flow is not increasing Slide 29 Act-PredStockFlowMar15: Act-PredStockFlow Error has increased recently, suggesting some blockage or flowmeter in need of calibration (reading high). If the flow is reading high, this could account for a lot of the lower cost. Slide 30 Is the Production Rate Accurate? If the production rate truly is reading higher than it actually is, reported costs will be lower. In addition to checking flow vs valve position, we can also calculate the correlation of amps on mixers, washers, tower level control OPs, etc. The next six slides all show a good correlation between this sample of production indicators and stated production rate. Slide 31 Cl2 tower level cntrl op: 16LIC007.OP Slide 32 D1 REPULPER AMPS LOAD: 16II119.PV Slide 33 E1 REPULPER AMPS LOAD: 16II118.PV Slide 34 1st NAOH Steam Mixer Amps: 16II122.PV Slide 35 CL2 REPULPER AMPS LOAD: 16II117.PV Slide 36 CL2 WSHR SPEED CTL: 16SIC17.OP Slide 37 Other Flows Slide 38 CL2 WSHR SPEED CTL: 16SIC17.PV Slide 39 CLO2 CNTRL VALVE OUTPUT: 16FIC009.OP Good correlation since March. Note the flow is not appreciably higher. Slide 40 D0 ClO2 Act-Pred Flow: D0 ClO2 Act-Pred Flow Error remains stable Slide 41 NAOH TO 1ST NAOH STAGE: 16FIC23.OP Recently the swinging has decreased; however correlation remains poor Slide 42 CLO2 TO 1ST CLO2 STG: 16FIC42.OP Continues to have poor correlation; the valve swings to 100 quite often. The flow is lower, supporting the contention costs are lower, but it is difficult to tell if the flow is accurate based on the swinging valve. Slide 43 D1 ClO2 Act-Pred Flow: D1 ClO2 Act-Pred Flow Since there is such a poor correlation between flow vs valve position, this is not useful Slide 44 E2 STM MXR NAOH FLOW CTL: 16FIC46.OP Flow decreased to zero while OP is maxed out. Is this being used? Is there another flow controller in use? Slide 45 CLO2 TO 2ND CLO2 TOWER: 16FIC62.OP Good correlation since March Slide 46 D2 ClO2 Act-Pred Flow: D2 ClO2 Act-Pred Flow Error remains stable Slide 47 Cost Correlations Slide 48 pH - D2 STAGE UPFLOW TUBE: 16PHC056.PV Costs have been lower since this pH increased 50%; r2=0.37 which is fairly high for 256 data points Slide 49 2nd CLO2 VAT pH: 16phi028.pv VAT pH is high with the increase in D2 upflow pH Slide 50 EO J-TUBE PRESSURE: 16PIC121.PV Costs have been lower since this pressure increased. There is a correlation to overall cost with r2=0.32 Slide 51 NaoH Steam Mixers We were asked to look at the 1 st Caustic Steam Mixer and determine if it correlates with the drop in ClO2 usage and brightness Above shows the EO steam mixer OP versus Total Costs Slide 52 EO STEAM MIX TEMP CONTRL: 16TIC24.OP OP dropping with total costs though PV is consistent at 180; lower since Apr 5 Slide 53 EO STEAM MIX TEMP CONTRL: 16TIC24 PV vs OP Note that the PV has been 180, but the valve output is much lower. Either the steam pressure is higher (cant find a tag for that) or the first ClO2 stage washer is more efficient (dryer mat); we can rule out the stated production rate is inaccurate. Slide 54 E2 STEAM MIX TEMP CONTROL: 16TIC47.OP E2 steam mixer shows the same trend. OP dropping with total costs though PV is consistent at 170. The OP is lower since May 14, well after the E1 caustic valve position dropped. Slide 55 E2 STEAM MIX TEMP CONTROL: 16TIC47 PV vs OP The PV has remained around 170, yet the OP is falling. Again, this would happened if the mat was dryer off the washer deck or if thesteam pressure was higher. In the case of pressure, we would expect them to drop on both E stages at the same time but that is not what we see. Slide 56 Total ClO2 usage lbs per ton: TotClO2Usage.pv Overall ClO2 usage (in red) has decreased with EO steam mixer temp OP (in blue), though correlation is weak Slide 57 CLO2 TO CL2 HI-SHEAR MIXER: 16FIC009.PV Poor correlation Slide 58 CLO2 TO 1ST CLO2 STG: 16FIC42.PV There is a correlation between D1 ClO2 and EO steam mix temp OP with r2=0.36. Slide 59 CLO2 TO 2ND CLO2 TOWER: 16FIC62.PV There is a slight correlation between D2 ClO2 and EO steam mix temp OP with r2=0.20 Slide 60 2ND NAOH VAT DIL FLO CTL: 16FIC54.PV Vat dilution has increased suggesting better drainage Slide 61 1st NAOH Steam Mixer Amps: 16II122.PV Steam mixer amps have increased with a decrease in OP Slide 62 D1 PULP BRIGHTNESS: 16D1BRIT.E At average values Slide 63 FINAL (D2) HW PULP BRITE: 16D2HWBR.ITE Decrease in Brightness was seen after the steam mixer OP had been decreasing for a couple months. Correlation is weak Slide 64 Recent Changes Bleach Plant Slide 65 DO Downleg Vacuum: 16DOVAC.MAN Vacuum decreased in June Slide 66 Weak Wash to Bleach Scrubber: 16FI029.PV Stepped up in June and currently at historic highs Slide 67 CL2 SEAL TANK LEV CTRL: 16LIC26.PV At historic high Slide 68 Recent Changes Digesters & BSW Slide 69 STEAM PER DIG HW: STDGHW.PV Steam use has been decreasing since May 26 Slide 70 DIGESTER 4 STEAM VLV OP: 14OP40.PV Digester 4 and 5 steam are both at historic lows Slide 71 ACCUM PRIMARY PRESS - VL: 14OP86.PV Decreasing with lower costs Slide 72 NCG VALVE OUTPUT: 14PIC87B.OP This increased, but it was essentially no change: it is maxed out. Slide 73 FILTRATE TO KNOT DRAINER: 15OP177.PV Pressure has been increasing since March Slide 74 SR Defoamer usage quality calc: 15sr_lbs.calc Defoamer usage has been lower with lower costs Slide 75 #1 BSW Downleg Vacuum: 15vi002c.pv Vacuum has been decreasing since Feb. Any air leaks? Slide 76 GEN PRES TREND POINT: 34OP343.PV Currently at historic high Slide 77 15% Caustic Density: 35DIC020.PV Continues to decrease Slide 78 FLOW - 50% CAUSTIC TO WL: 35FC040.OP Currently at historic high Slide 79 Brownside HW Prod Bias: Brncons.hwbias Currently at historic high but did not change when costs fell