Optimization and efficiency are key to improve processes and achieve actual savings at the same time. Sometimes it’s just a matter of adopting simple devices, which can yet help achieve good results. Let’s discover how three suppliers from the industry conceive energy saving.
Energy efficiency is strongly dependent on the careful choice of the installed solutions, i.e. devices small and big that do not necessarily influence the paper mill production process and yet make it possible for it to achieve major energy savings.
Three leading suppliers from the paper industry concentrated all their efforts exactly on this and focussed on energy saving with the aim of presenting their customers with tangible results obtained thanks to innovative technologies.
Efficiency in the front line
As Michele Ghibellini of Officine Airaghi explains, the open house event organized by Tecno Paper in Lucca (Italy) on 25th and 26th March 2015 provided the ideal setting to present the new special shaftless rewinder.
«In times of crisis new opportunities are discovered and what one already has is used in a more rational way. It is therefore necessary to understand what variables within a paper mill are often not considered, which can immediately help optimize the paper mill work and production system. Only then is it possible to further rationalize energy savings and productivity».
Due to rising energy costs and the need to preserve raw materials a debate on energy savings is necessary, as pointed out by Andrea Rodolfi of Cutes Europe; «these types of events enable us to share different views on the topic and better understand both the needs and the perplexities of our customers, who will ultimately have to find an answer in our solutions».
The focus is an occasion to present paper mills, also the smallest ones, with energy efficiency solutions. Paolo Andrighetti of Sael explains that while big and well structured paper mills devote proper resources to energy management and control, small and medium-sized ones tend to consider these aspects of secondary importance. To this end, «we launched an awareness-raising campaign targeted to paper mills, during which Sael provides a free energy detection system for one year. The software, which is simply to be installed on a PC and connected to the measuring instruments on the field by the paper mill, makes it possible to carry out a selective monitoring activity in all plant departments and record energy variables with sampling per second, thereby delivering the corresponding statistics. This is a fundamental starting point for a smart analysis and the planning of measures that can be adopted in certain areas of the plant».
The «hot» points of the process
The first step towards energy efficiency lies in identifying those steps in the paper making process that can be improved; one of them is stock preparation. «Energy consumption in this area makes up for about 30% of the total energy consumed in the paper mill», says Mr. Ghibellini. «A minor modification at this stage of production can lead to major changes at the level of the final product, that is why there has always been some hesitation in changing the machines working parameters. However, an increasingly strong interest is currently being shown for refiners and deflakers. As far as we are concerned we have shown how it is possible to optimize, through the use of our non conventional products like EFP® and CNConic®, those machines and installations that are oversize compared to actual needs or conversely up to their use limit with traditional spare parts. We therefore aim at providing technical support in the stock preparation to plan and produce tailor-made fillings enabling our customers to reach the ideal value, which perfectly combines refining results with the energy and maintenance costs».
The pulper, vacuum and refining areas are often erroneously underestimated and yet they are areas which, in the words of Mr. Andrighetti, are a highly energy-consuming sector. «That is why it is important to carry out constant check and regulation activities. This can be done by means of inverters that have been designed ad hoc for pulper applications, including high-density ones, and feature various regulation applications inside, thanks to which the machine can be started again even after a full-load standstill», he explains. The substantial energy overstatement on the machines should also be considered. «Although this appears to provide more autonomy at first sight, it implies in fact a waste of energy during constant normal operation. A control system therefore becomes indispensable, as it enables to achieve remarkable energy savings in just few months with a quick payback of the investment».
Mr. Rodolfi believes, too, that «optimizing the vacuum system that uses a large share of the energy bound for the production cycle, up to 20-25% of the total, can markedly impact on the reduction of specific consumption per ton of paper produced. From this point of view, our modular system can help bring about major results in terms of efficiency, especially if the system is combined with the correct distribution of the vacuum resource through an optimized network both to avoid useless air expansion and to use pipes of the correct size».
Advantages worth considering
Optimizing the production cycle is of course an investment for paper mills. Any cost, especially in times of crisis, is carefully assessed, hence the immediate advantages connected with the proposed solutions and their related payback are decisive factors for decision-making. On this, Mr. Andrighetti points out that the advantages of automation and regulation with inverters are manifold. He tells us that «an Italian paper making group, which is a customer of ours, analysed the savings that could be obtained for any area of the plant and bought two pulpers with the money saved. Our solution furthermore enabled them to carry out a detailed monitoring activity of the energy absorbed to document and apply for the release of energy efficiency certificates. Our solution provides for diagnostics and the operation of the installation, together with the possibility to calculate the amount of kWh absorbed per ton of pulped raw material. The investment led to a twofold effect of energy saving and promotion of the energy efficiency certificates and had a payback time of six months alone».
Officine Airaghi, instead, aims at the extreme and differentiated customization of its products. As Mr. Ghibellini explains, «this allows the paper mill not to incur in any special costs». This also means that the paper mill can «benefit from the energy savings and the savings related to the refining process from the very beginning, without having to allocate higher costs compared to traditional spare parts. Furthermore, thanks to our milling production process we can rework the same Airaghi product used by the customer and process it with our new solutions with a 30% economical saving on the price of the new filling».
System reliability and adequate investment and management costs are at very basics of the efficiency concept as Rodolfi understands it. «Our wide range of products enables us to propose the machine in the right size for any vacuum position and level. Furthermore, a careful on-site analysis of the system and the use of more adequate components make it possible to achieve higher energy savings, often without completely altering the already existing system. The investment payback times vary depending on several variables; in very extreme cases they can even be 6-7 months».
Acting on the global market
The real challenge today is competing on a market that has now become international. «We shall definitely have to turn from suppliers alone to advisors and increasingly take on the role of a partner for our customer». Mr Rodolfi believes that «this makes it possible for us to guarantee customized technical assistance and identify the best investment possible between the suggested solutions, in order to turn what is by definition considered a cost into a real competitive advantage».
As Mr. Ghibellini points out, the answer lies in a strong sector-specific specialization; «technological innovation and totally Made-in-Italy products are the answer we should give to the national and international paper-making industry, thereby levering ourselves on the creativity and adaptability that are typical of our culture and can serve as a guarantee to design and produce first-quality items. R&D lies at the core of any course of growth; yet, at the same time this development should be sustainable and not only consider variables of mere economic profit».
As regards automation and actuations, Mr. Andrighetti highlights the importance of production adjustments and, above all, the analysis of production cycles, also in terms of management. «Automation performed in view of energy savings pays back and contributes to major reductions in production costs. The network between Sael, Cutes Europe and Officine Airaghi», he concludes, «was created to raise awareness among all our customers and induce them to seriously consider and start this activity after the feedback obtained from the installations performed over the years».
Officine Airaghi has developed new products, which obtained international patents and combine two fundamental aspects in the stock preparation: customization and energy saving. EFP® – for disc refiners – and CNConic® – for conical refiners – have been designed to improve refining parameters, thereby guaranteeing a lower and more calibrated use of energy. These fittings can always be modified. Furthermore, thanks to its manufacturing and milling methods the company is able to produce high-precision mechanical parts in their sizes and with constant performance over their entire lifecycle.
Cutes Europe presents the Vakuodrive system, which has been developed in collaboration with Sael. The system provides makes the air volumes from the pumps flexible and modular compared to the vacuum levels needed by the installations. A series of algorithms directly managed by the system make it possible to optimize the performance of the pump compared to the actual needs of the machine. The system application on the blanket conditioning part is exceptional, as changes in the permeability of the blanket correspond to changes in capacity and vacuum levels.
Finally, the new smart inverters with control software – i.e. an extension of the Platform one range – are the energy saving solution proposed by Sael in collaboration with Officine Airaghi and Cutes Europe. They are extremely flexible and feature a process regulation board with a high calculation power, well beyond the engine speed variation. They have been prepared with several onboard software applications to meet the energy saving needs in the fields of refining and management of vacuum pumps and in the operation of pulpers. Furthermore, the new inverters make it possible to connect and communicate with all the management systems used in the paper mill.