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Table3. Total energy savings over 10 years.
Year
1
2
3
4
5
6
7
8
9
10
Production days
344.5 351.0 350.2 345.0 341.0 313.7 339.0 335.0 334.0 317.0 121.3 124.2 127.6 133.2 131.3 133.5 134.9 135.6 134.1 137.6 9833 11,523 13,647 10,686 7111 4404 3951 2917 1449 2129
Paper production (t) Blowdown loses MJ
Savings Blowdown energy MJ Savings Exchangers energy MJ
4310 7017 7470 8504 9972 9292
0 24,191 23,923 25,547 Total Energy consumption 144,347 147,798 151,844 158,508 150.995 152.857 153,786 137,172 135,655 139,196 Total Energy Savings 4310 7017 7470 32,695 33.895 34,839 0 0 0 0 0 0
Figure 5 shows the evolution of the annual average of the indicator, which gradually declines in value over time. The indicator ‘t CO 2 /t Paper’ decreases by an average of 21% from year 2 to 10 and by approximately 30% since year 1.
Figure5. Evolution of the indicator—“t CO 2 /t Paper” over 10 years. In Figure 5, there is a stable zone indicator value in the first four years that represents a period in which the indicator remains stable because there are no actions for reducing emissions. After applying TPM techniques such as TEI to motivate maintenance and production personnel and CPI actions (small changes, especially considering employee observations) at the end of 4 years and regarding maintenance, at three levels, from year 5 onward, the indicator is starts to improve until it reaches 0.2300 in years 9 and 10. Figure 6 is divided into three sections to clarify the data interpretation and facility analysis. The first section contains the data for the years preceding year 1 and year 1 inclusive, a period that had no active EU ETS emissions scheme. The second dataset contains data from years 2–4, which corresponds to the implementation of the first period of the EU ETS. The third section includes the data from year 5 to the present, including the second period of the EU ETS and the first year of the third period of the EU ETS. Figure 6 shows that the indicator under consideration declines gradually each year, which becomes apparent starting in year 8. Figure 6a–c also shows the variation in the index over the twelve months of the year; the outside temperature is colder in the winter months (1, 2, 11, and 12) than in the remaining months, which increases the importance of controlling the blown air temperature (Ebt). The indicator progressively decreases in each period, as seen by the first year (white) in Figure 6a to the last year (black) in Figure 6c. In all graphs of Figure 6, the difference between the first and last years is evident. Reviewing the three graphs reveals that the same indicator level is maintained on the ordinate and decreases significantly and steadily until year 5, where we see a further decline; this coincides with the start of the leading indicator ‘t CO 2 /t Paper’.
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