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world pulppaper 63 Several studies revealed the opportunity to reduce the electricity consumption without compromising and often actually improving the machine efficiency ImprovIng product qualIty Advancements in instrumentation have opened new avenues for effective use of vacuum table elements to control sheet consistency this has led to a variety of papermaking applications including dandy rolls for improved formation multiple formers for optimum formation coverage and ply bond as well as numerous chemical dosage applications. Several studies performed on different former configurations including traditional Fourdriniers revealed the opportunity to reduce the electricity consumption without compromising and often actually improving the machine efficiency. Fig.2 provides a good example of what can happen when too high vacuum is applied to a gap former producing white top liner. The consistency levels in the two critical points before the ply-bonding and the couch roll remain almost unchanged although there is a decrease of low vacuum zone about 50. In addition a better distribution of the dewatering between the low and medium vacuum zones leads to a better paper quality with greater strength properties. optImISatIon of the energy conSumptIon The optimisation of the energy consumption in the paper machine consists of expending the necessary energy only where it is required and thus avoiding wasted energy that might lead to excessive wear of the machine elements forming fabrics ceramics motors and pumps. figure 2. Drive load saving Sheet formatIon vS. conSIStency at ply bond The formation of each single ply has a direct impact on the formation of the entire board. Dewatering can be optimised in order to achieve the best sheet properties. Water distribution is a key factor in water removal and energy consumption. figure 3. Consistency measurement ply bond figure 2. Drive load saving On-line monitoring of the ply consistency allows dewatering optimisation and to obtain specific settings by paper grade. An example of this is the evident improvement of sheet formation with 50 vacuum reduction on the gap former Fig.3.