Acidic dissolution of iron oxides and regeneration of a ceramic filter medium

The dewatering of iron ore concentrates requires large capacity in addition to producing a cake with low moisture content. Such large processes are commonly energy intensive and means to lower the specific energy consumption are needed. Ceramic capillary action disc filters incorporate a novel filter medium enabling the harnessing of capillary action, which results in decreased energy consumption in comparison to traditional filtration technologies. As another benefit, the filter medium is mechanically and chemically more durable than, for example, filter cloths and can, thus, withstand harsh operating conditions and possible regeneration better than other types of filter media. In iron ore dewatering, the regeneration of the filter medium is done through a combination of several techniques: (1) backwashing, (2) ultrasonic cleaning, and (3) acid regeneration. Although it is commonly acknowledged that the filter medium is affected by slurry particles and extraneous compounds, published research, especially in the field of dewatering of mineral concentrates, is scarce. Whereas the regenerative effect of backwashing and ultrasound are more or less mechanical, regeneration with acids is based on chemistry. The chemistry behind the acid regeneration is, naturally, dissolution. The dissolution of iron oxide particles has been extensively studied over several decades but those studies may not necessarily be directly applicable in the regeneration of the filter medium which has undergone interactions with the slurry components. The aim of this thesis was to investigate if free particle dissolution indeed correlates with the regeneration of the filter medium. For this purpose, both free particle dissolution and dissolution of surface adhered particles were studied. The focus was on acidic dissolution of iron oxide particles and on the study of the ceramic filter medium used in the dewatering of iron ore concentrates. The free particle dissolution experiments show that the solubility of synthetic fine grained iron oxide particles in oxalic acid could be explained through linear models accounting for the effects of temperature and acid concentration, whereas the dissolution of a natural magnetite is not so easily explained by such models. In addition, the kinetic experiments performed both support and contradict the work of previous authors: the suitable kinetic model here supports previous research suggesting solid state reduction to be the reaction mechanism of hematite dissolution but the formation of a stable iron oxalate is not supported by the results of this research. Several other dissolution mechanisms have also been suggested for iron oxide dissolution in oxalic acid, indicating that the details of oxalate promoted reductive dissolution are not yet agreed and, in this respect, this research offers added value to the community. The results of the regeneration experiments with the ceramic filter media show that oxalic acid is highly effective in removing iron oxide particles from the surface of the filter medium. The dissolution of those particles did not, however, exhibit the expected behaviour, i.e. complete dissolution. The results of this thesis show that although the regeneration of the ceramic filter medium with acids incorporates the dissolution of slurry particles from the surface of the filter medium, the regeneration cannot be assessed purely based upon free particle dissolution. A steady state, dependent on temperature and on the acid concentration, was observed in the dissolution of particles from the surface even though the limit of solubility of free iron oxide particles had not been reached. Both the regeneration capacity and efficiency, with regards to the removal of iron oxide particles, was found to be temperature dependent, but was not affected by the acid concentration. This observation further suggests that the removal of the surface adhered particles does not follow the dissolution of free particles, which do exhibit a dependency on the acid concentration. In addition, changes in the permeability and in the pore structure of the filter medium were still observed after the bulk concentration of dissolved iron had reached a steady state. Consequently, the regeneration of the filter medium continued after the dissolution of particles from the surface had ceased. This observation suggests that internal changes take place at the final stages of regeneration. The regeneration process could, in theory, be divided into two, possibly overlapping, stages: (1) dissolution of surface-adhered particles, and (2) dissolution of extraneous compounds from within the pore structure. In addition to the fundamental knowledge generated during this thesis, tools to assess the effects of parameters on the regeneration of the ceramic filter medium are needed. It has become clear that the same tools used to estimate the dissolution of free particles cannot be used to estimate the regeneration of a filter medium unless only a robust characterisation of the order of regeneration efficiency is needed.

Green Marketing and its Role in Firm’s Strategy

Tässä kandidaatintutkielmassa tutkitaan vihreän markkinoinnin strategista roolia ja sen tuomaa lisäarvoa yritykselle. Tutkimuksessa selvitetään, mitä vihreä markkinointi on, mistä syistä yritykset harjoittavat sitä ja tuoko se lisäarvoa yritykselle. Case-yrityksinä tutkielmassa ovat UPM-Raflatac ja Lappeenrannan Energia Oy.

Grey literature, green open access: the BLDS Digital Library

Presentation at Open Repositories 2014, Helsinki, Finland, June 9-13, 2014

AQUAREL CONCEPT Aquatic resources for green energy realization

The AQUAREL project studied the availability and optional utilization methods for fish processing side streams and other aquatic biomaterial in the Republic of Karelia. Additionally processing aquatic biomaterial with manure and sewage sludge was studied. Based on the results, the most feasible option today is to process fish side streams to fish oil and dewatered oil-free residue and to use them for fish or animal feed production. However, it is necessary to highlight, that changes in e.g. economic environment, energy prices and demand may require re-evaluating the results and conclusions made in the project. Producing fish oil from fish processing side streams is an easy and relatively simple production process generating a valuable end product. The functionality of the process was confirmed in a pilot conducted in the project. The oil and solids are separated from the heated fish waste based on gravity. The fish oil separating on top of the separator unit is removed. Fish oil can as such be utilized for heating purposes, fish meal or animal feed production, but it can also be further processed to biodiesel. However, due to currently moderate energy prices in Russia, biodiesel production is not economically profitable. Even if the fish oil production process is not complicated, the operative management of small-scale fish oil production unit requires dedicated resources and separate facilities especially to meet hygiene requirements. Managing the side streams is not a core business for fish farmers. Efficient and economically profitable fish oil production requires a centralized production unit with bigger processing capacity. One fish processing unit needs to be designed to manage side streams collected from several fish farms. The optimum location for the processing unit is in the middle of the fish farms. Based on the transportation cost analysis in the Republic of Karelia, it is not economically efficient to transport bio-wastes for more than 100 km since the transportation costs start increasing substantially. Another issue to be considered is that collection of side streams, including the dead fish, from the fish farms should be organized on a daily basis in order to eliminate the need for storing the side streams at the farms. Based on AQUAREL project studies there are different public funding sources available for supporting and enabling profitable and environmentally sustainable utilization, research or development of fish processing side streams and other aquatic biomaterial. Different funding programmes can be utilized by companies, research organizations, authorities and non-governmental organizations.

Green supplier selection via Multiple Criteria Data Envelopment Analysis

An appropriate supplier selection and its profound effects on increasing the competitive advantage of companies has been widely discussed in supply chain management (SCM) literature. By raising environmental awareness among companies and industries they attach more importance to sustainable and green activities in selection procedures of raw material providers. The current thesis benefits from data envelopment analysis (DEA) technique to evaluate the relative efficiency of suppliers in the presence of carbon dioxide (CO2) emission for green supplier selection. We incorporate the pollution of suppliers as an undesirable output into DEA. However, to do so, two conventional DEA model problems arise: the lack of the discrimination power among decision making units (DMUs) and flexibility of the inputs and outputs weights. To overcome these limitations, we use multiple criteria DEA (MCDEA) as one alternative. By applying MCDEA the number of suppliers which are identified as efficient will be decreased and will lead to a better ranking and selection of the suppliers. Besides, in order to compare the performance of the suppliers with an ideal supplier, a “virtual” best practice supplier is introduced. The presence of the ideal virtual supplier will also increase the discrimination power of the model for a better ranking of the suppliers. Therefore, a new MCDEA model is proposed to simultaneously handle undesirable outputs and virtual DMU. The developed model is applied for green supplier selection problem. A numerical example illustrates the applicability of the proposed model.

Reporting of Green Supply Chain Management and Industrial Symbiosis

The purpose of this thesis is to examine how the reporting of operations related to green supply chain management and industrial symbiosis has evolved in UPM, Fortum and Kemira within the last ten years. The focus is on the improved operations, which are studied based on annual reports of these companies. The study provides a deeper understanding of the nature of green supply chain management and industrial symbiosis as well as the possibilites that their combination offers. The research is part of the DemaNET research project The study indicates that the environmental regulations and reporting standards have forced the studied companies to report their operations related to green supply chain management and industrial symbiosis more in detail during the last ten years. The operations related to green supply chain management in the studied companies are more common compared to operations related to industrial symbiosis. Often these two operations were also partially integrated, indicating a hybrid model. Even though firms often used hybrid models they still focused mainly on greening the internal operations rather than finding alternative ways for symbiosis outside the organization. The integration of green supply chain management and industrial symbiosis is most likely to occur when mutually beneficial relationships align the interests of all parties, thus resulting in the co-creation of value. The findings suggest that identifying mutual benefits and the flow of by-products are the ones that companies should give more attention to.

Green aspects study in game development

Context: Game development has become increasingly important in the software industry, but this importance has not affected the way software engineering approaches and methodologies manage the differences they have with game development. Similarly, software engineering does not fully support sustainability practices, causing this element to often not be considered or even known as a requirement for a development lifecycle. Goal: The aim of this thesis is to study the mode in which games are developed, and the involved sustainable aspects and the relevant concerns regarding the migration processes. Method: A quantitative study was conducted, gathering 33 answers of game professionals from four continents, from administrative (25%) and technical oriented positions (75%). Results: Three trends were observed: 1) Agile process models are used, 2) major concerns for mobile development and digital marketing, 3) minor concerns for eco-impact elements and certain development phases such as testing and crunch time development. Conclusion: Traditional Software engineering would require a major change on its processes and models to fit with modern agile development, game development approaches and sustainable requirements.

Green welding in practice

Efficient production and consumption of energy has become the top priority of national and international policies around the world. Manufacturing industries have to address the requirements of the government in relation to energy saving and ecologically sustainable products. These industries are also concerned with energy and material usage due to their rising costs. Therefore industries have to find solutions that can support environmental preservation yet maintain competitiveness in the market. Welding, a major manufacturing process, consumes a great deal of material and energy. It is a crucial process in improving a product’s life-cycle cost, strength, quality and reliability. Factors which lead to weld related inefficiencies have to be effectively managed, if industries are to meet their quality requirements and fulfil a high-volume production demand. Therefore it is important to consider some practical strategies in welding process for optimization of energy and material consumption. The main objective of this thesis is to explore the methods of minimizing the ecological footprint of the welding process and methods to effectively manage its material and energy usage in the welding process. The author has performed a critical review of the factors including improved weld power source efficiency, efficient weld techniques, newly developed weld materials, intelligent welding systems, weld safety measures and personnel training. The study lends strong support to the fact that the use of eco-friendly welding units and the quality weld joints obtained with minimum possible consumption of energy and materials should be the main directions of improvement in welding systems. The study concludes that, gradually implementing the practical strategies mentioned in this thesis would help the manufacturing industries to achieve on the following - reduced power consumption, enhanced power control and manipulation, increased deposition rate, reduced cycle time, reduced joint preparation time, reduced heat affected zones, reduced repair rates, improved joint properties, reduced post-weld operations, improved automation, improved sensing and control, avoiding hazardous conditions and reduced exposure of welder to potential hazards. These improvement can help in promotion of welding as a green manufacturing process.

Implementing Green IT approach for transferring Big Data over Parallel Data Link

The whole research of the current Master Thesis project is related to Big Data transfer over Parallel Data Link and my main objective is to assist the Saint-Petersburg National Research University ITMO research team to accomplish this project and apply Green IT methods for the data transfer system. The goal of the team is to transfer Big Data by using parallel data links with SDN Openflow approach. My task as a team member was to compare existing data transfer applications in case to verify which results the highest data transfer speed in which occasions and explain the reasons. In the context of this thesis work a comparison between 5 different utilities was done, which including Fast Data Transfer (FDT), BBCP, BBFTP, GridFTP, and FTS3. A number of scripts where developed which consist of creating random binary data to be incompressible to have fair comparison between utilities, execute the Utilities with specified parameters, create log files, results, system parameters, and plot graphs to compare the results. Transferring such an enormous variety of data can take a long time, and hence, the necessity appears to reduce the energy consumption to make them greener. In the context of Green IT approach, our team used Cloud Computing infrastructure called OpenStack. It’s more efficient to allocated specific amount of hardware resources to test different scenarios rather than using the whole resources from our testbed. Testing our implementation with OpenStack infrastructure results that the virtual channel does not consist of any traffic and we can achieve the highest possible throughput. After receiving the final results we are in place to identify which utilities produce faster data transfer in different scenarios with specific TCP parameters and we can use them in real network data links.

Benchmark of routing protocols regarding green considerations

In Mobile Ad-hoc Networks (MANET) the participating nodes have several roles such as sender, receiver and router. Hence there is a lot of energy consumed by the nodes for the normal working of the network since each node has many different roles. Also in MANET the nodes keep moving constantly and this in turn consumes a lot of energy. Since battery capacity of these nodes is limited it fails to fulfil the high demand of energy. The scarcity of energy makes the energy conservation in mobile ad-hoc networks an important concern. There is several research carried out on the energy consumption of mobile ad-hoc networks these days. Some of this research suggests sleep mode, transmission power control, load balancing etc. In this thesis, we are comparing various proposed energy efficient models for some of the ad-hoc protocols. We compare different energy efficient models for Optimised Linked State Algorithm (OLSR) and Ad-hoc On Demand Distance Vector (AODV). The routing protocols are compared for different parameters such as average remaining energy, number of nodes alive, payload data received and performance with different mobility speed. The simulation results helps in benchmarking the various energy efficient routing models for OLSR and AODV protocols. The benchmarking of the routing protocols can be based on many factors but this thesis concentrates on benchmarking the MANET routing protocols mainly based on the energy efficiency and increased network lifetime.

Green Service Level Agreement under Sustainability Lens in IT Industry

Nowadays, when most of the business are moving forward to sustainability by providing or getting different services from different vendors, Service Level Agreement (SLA) becomes very important for both the business providers/vendors and as well as for users/customers. There are many ways to inform users/customers about various services with its inherent execution functionalities and even non-functional/Quality of Services (QoS) aspects through negotiating, evaluating or monitoring SLAs. However, these traditional SLA actually do not cover eco-efficient green issues or IT ethics issues for sustainability. That is why green SLA (GSLA) should come into play. GSLA is a formal agreement incorporating all the traditional commitments as well as green issues and ethics issues in IT business sectors. GSLA research would survey on different traditional SLA parameters for various services like as network, compute, storage and multimedia in IT business areas. At the same time, this survey could focus on finding the gaps and incorporation of these traditional SLA parameters with green issues for all these mentioned services. This research is mainly points on integration of green parameters in existing SLAs, defining GSLA with new green performance indicators and their measurable units. Finally, a GSLA template could define compiling all the green indicators such as recycling, radio-wave, toxic material usage, obsolescence indication, ICT product life cycles, energy cost etc for sustainable development. Moreover, people’s interaction and IT ethics issues such as security and privacy, user satisfaction, intellectual property right, user reliability, confidentiality etc could also need to add for proposing a new GSLA. However, integration of new and existing performance indicators in the proposed GSLA for sustainable development could be difficult for ICT engineers. Therefore, this research also discovers the management complexity of proposed green SLA through designing a general informational model and analyses of all the relationships, dependencies and effects between various newly identified services under sustainability pillars. However, sustainability could only be achieved through proper implementation of newly proposed GSLA, which largely depends on monitoring the performance of the green indicators. Therefore, this research focuses on monitoring and evaluating phase of GSLA indicators through the interactions with traditional basic SLA indicators, which would help to achieve proper implementation of future GSLA. Finally, this newly proposed GSLA informational model and monitoring aspects could definitely help different service providers/vendors to design their future business strategy in this new transitional sustainable society.

Green ICT metrics and Biomimicry

Sustainability issue of ICT have gathered attention in recent years, and researchers are working on this problem. Sustainability incorporates numerous interconnected aspects as well as methods to achieve it in ICT, so it is quite complicated to have a general view on a problem without a proper framework. However, a general methodology for such a research is missing. In this work it is proposed to use Biomimicry approach as a framework for sustainability research and development, as it introduces systematics and also forces to account sustainable aspects. Additionally, an interesting problem of green network measurements for enhancing sustainability in ICT will be researched using mentioned approach. The goal is to investigate Biomimicry as a systemic approach for developing sustainable systems, as well as to apply it in green network measurements study. Comparative study is performed for examining Biomimicry approach, as well as a use case of green network measurements research is presented. As a result, green network measurement can potentially improve sustainability, but only to a limited extent as it cannot incorporate all the aspects; within Biomimicry approach, two methodologies exist. It is possible to conclude that Biomimicry is a good framework for developing sustainable systems, nevertheless, another methodology has to be introduced within it; new methodology has to incorporate advantages of two existing ones.

“Good night, dear Lake of Shining Waters”. Luonto L. M. Montgomeryn Anne of Green Gables –teoksessa

Kanadalaisen kirjailijan L. M. Montgomeryn tunnetun ja rakastetun Anna-sarjan ensimmäinen osa Anne of Green Gables -teos (1908) kertoo orvosta tytöstä, joka pääsee Prinssi Edwardin saaren Avonlean kylään asumaan naimattoman sisarusparin Marilla ja Matthew`n kasvattilapseksi. Luonto on keskeisellä sijalla teoksessa: Anna on luontoa rakastava ja luonnon keskellä viihtyvä tyttö ja myös teoksen kertoja kuvaa paljon luontoa. Tutkimukseni käsittelee luontoa Anne of Green Gables -teoksessa. Tutkin luontoteemaa teoksessa seuraavista näkökulmista: Analysoin, kuinka luonto kuvataan teoksessa ja millainen on teoksen luontokuva. Luontokuvaa käsittelen pastoraalin käsitteen kautta, ja kysyn teokselta, voidaanko se tulkita pastoraaliksi ja kuinka teos asettuu pastoraalin traditioon. Lisäksi erittelen, millainen on päähenkilön Annan luontosuhde. Millaisen arvon hän antaa luonnolle ja mitä merkityksiä hän liittää luontoon? Tutkimus asettuu ekokriittiseen viitekehykseen, ja pohdin myös sitä, minkälainen on teoksen representaatio luonnosta ekokriittisesti tarkastellen. Amerikkalaisen transsendentalistin Ralph Waldo Emersonin luontofilosofia kulkee myös taustajuonteena tutkielmassa ja erittelen, mitä yhtymäkohtia hänen luontofilosofiassaan on Anne of Green Gables -teokseen. Anne of Green Gables -teoksen luontokuvaa voidaan luonnehtia romantisoiduksi ja idealisoivaksi. Luonto kuvataan kauniiksi, ja sen kauneutta ylistää niin Anna kuin teoksen kaikkitietävä kertojakin. Teoksen luontokuva on pastoraalinen, sillä siinä esiintyy vahvasti pastoraaliin liittyvä diskurssi maaseudun ja kaupungin vastakkainasettelusta siten, että maaseutu assosioituu positiivisesti, kun taas kaupunki nähdään negatiivisessa valossa. Luonnonläheinen Avonlean kylä näyttäytyy teoksessa niin idealisoidussa valossa, että se muistuttaa jo jonkinlaista myyttistä paratiisia. Näin ollen teoksen pastoraalisuus saa pejoratiivisiakin piirteitä. Annan luontosuhdetta värittää voimakas kunnioitus ja arvostus luontoa kohtaan. Hänen luontoon liittämistä arvoista keskeiselle sijalle nousee luonnon kauneus. Luonnon kauneuden arvostaminen toimii kuitenkin porttina luonnon toiseuttamiseen, mistä syntyy pieni arvoristiriita. Toisaalta kuitenkin Anna samaistuu luontoon tavalla, joka hämärtää perinteistä subjekti–objekti-dikotomiaa. Anna näyttäytyy vihreän maailman arkkityyppinä, lapsena, joka sulautuu luontoon ja kokee sen kodikseen. Luonto edustaa Annalle vapautta ja herättää myös hänen mielikuvituksena ja taiteellisen inspiraation. Lisäksi luonto on Annalle paikka, jossa voi saavuttaa autenttisen yhteyden Jumalaan.