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The use of xanthates at the flotation of sphalerite raises questions about the sustainability of the process, due to the negative environmental impact. In addition, the development of local bio-collectors production is necessary to replace currently utilized flotation collectors and depressants, which are manufactured mostly in China. In this study we investigate the performance of lignin nanoparticles as sphalerite collectors in combination with xanthates. Among the parameters tested are replacement ratio, dilution temperature and lignin type. Interestingly, the partial replacement of xanthate collectors with bio collector lignin is viable. We tested a variety of attributes such as concentration, lignin types and sizes with a 3-stage flotation. After evaluation of the products is showed that a 50% replacement of collector with lignin does not affect the sphalerite grades and recovery, while decreasing the recovery of the gangue mineral (Au), thus leading to improved selectivity.

Conventional perlite expansion suffers certain well-known shortcomings compromising its viability and the adherence of expanded perlite to modern technical specifications for high-quality insulation materials. A new perlite expansion process has been designed and a vertical electrical furnace for perlite expansion has been constructed to overcome such drawbacks, with concurrent modeling studies (Angelopoulos et al., 2013 [1]). Having already accomplished the production of various expanded perlite grades for many varying applications,the entire state space of product quality against key manipulated variables has also been explored, and ideal experimental condition ranges for process operation have also been identified (Angelopoulos et al., 2013 [2]). Response Surface Methodologies (RSM) have an long track record of contribution to substantial improvements in many advanced chemical and material processing technologies. Their fundamental principle is the systematic exploration and statistical correlation of input (conditional) and output (response) variables with respect to interactions (if any) of the former and their combined effect (if any) on the latter – thus on end product quality. This paper focuses on using parametric sensitivity analysis results from the published furnace dynamic model as well as original experimental furnace results towards extracting a new three-dimensional RSM model which achieves an accurate correlation of both pivotal experimental variables (furnace temperature, air flowrate) with their combined effect on a known end-product quality metric (grain expansion factor): optimal condition ranges can thus be derived via bivariate quadratic polynomial fits for any plant and any raw perlite feed composition.

Expanded perlite has outstanding thermal and acoustic insulating properties and is widely used in the manufacturing and construction industries. The conventional perlite expansion method has certain disadvantages which affect the quality of expanded perlite products, thus limiting their performance and range of applications. A new perlite expansion process has been designed and a vertical electrical furnace for perlite expansion has been constructed in our laboratory in order to overcome these drawbacks, enabling precise control of experimental conditions in order to prescribe the temperature profile and residence time within the new heating chamber. A novel dynamic model for perlite grain expansion has been developed and validated so as to study and optimize the new furnace operation. Perlite ore origin, size distribution and water content are key parameters affecting expanded perlite quality. Moreover, air feed flow rate and temperature, as well as the imposed wall temperature distribution along the heating chamber are experimentally known to have a profound, measurable effect on grain residence time and expansion. A detailed sensitivity analysis has been performed so as to quantitatively understand the effect and relative importance of all foregoing operational parameters on macroscopic furnace operation (perlite particle velocity and temperature evolution) as well as on inaccessible microscopic characteristics (internal steam bubble pressure and size). Perlite grain radius and expansion ratio are probed in detail as a function of time, and furnace operation can be tuned vs. feed variation toward optimal product quality. Particle critical characteristics along trajectories as well as final particle size plots are presented; also, optimal furnace operating condition ranges are determined for variable initial size and water content.

Air freight sector has been a growing market worldwide for many years. The rapid growth of scheduled freight aircraft services in particular has been a remarkable feature of the international airline industry during the past decades. Air freight traffic has grown faster than passenger traffic and the production of goods has become more dependent upon air freight services that link global supply chains together. Air transportation is useful when the goods must be delivered quickly and it also allows for more flexible hub-and-spoke networking structures, which are able to offset some of the problems of indirect flows. The concept of developing regional air-cargo centres can be seen from many different perspectives. The most important factors in airport location selection are connectivity to existing road and rail transport networks and current or potential freight traffic volumes. Right location allows firms to develop their own resources, consolidate their competitive position and nurture their growth. Once the company has located it is hard to relocate, so that is why the location decision has to be made carefully. Purpose: The main purpose of this thesis was to reveal the key factors, either positive or negative, which can affect the decision of air freight operators to relocate their express services to smaller airports. Methodology: The chosen method for this thesis was the mono method because the data collection technique was qualitative. Based on that interviews, the authors finalized their topic and their research questions and built question lists, one for the Jönköping airport (Axamo), one for the companies that already operate in Jönköping airport and one for companies that do not operate there. The authors decided to have semi-structured interviews with all the interviewees in order to cover the different themes of their research. Findings: The main findings from analysing the empirical data revealed that there are many different positive and negative factors that can affect the decision making for relocation of freight operators. The most important that were identified concern the airport’s infrastructure, location, quality of provided services, number of passenger flights and price policy. Moreover, the weather conditions at the region, the customers’ demand and connectivity with road and rail networks are also very influential.

Expanded perlite has outstanding thermal and acoustic insulating properties and is widely used in the manufacturing and construction industries. The conventional perlite expansion method suffers disadvantages which affect the quality of expanded perlite products, thus limiting their performance and range of applications. A new perlite expansion process has been designed and a vertical electrical furnace for perlite expansion has been constructed in our laboratory in order to overcome these drawbacks, enabling precise control of experimental conditions, so as to prescribe the temperature profile and residence time in the heating chamber. Perlite ore origin, size distribution and water content are critical parameters affecting expanded perlite quality; air feed flow rate and temperature, as well as the imposed wall temperature distribution along the chamber are also experimentally known to have a profound, measurable effect on perlite grain residence time and expansion. A detailed sensitivity analysis has been performed in order to quantitatively understand the effect and relative importance of all these operational parameters on macroscopic furnace operation (perlite particle velocity and temperature evolution) and inaccessible microscopic characteristics (internal steam bubble pressure and size), based on a new dynamic model for perlite grain expansion we have developed towards furnace optimization [1].

Expanded perlite has outstanding thermal and acoustic insulating properties and is widely used in the manufacturing and construction industries. The conventional perlite expansion method suffers disadvantages which affect the quality of expanded perlite products, thus limiting their performance and range of applications. A new perlite expansion process has been designed and a vertical electrical furnace for perlite expansion has been constructed in our laboratory to overcome these drawbacks: the new design enables precise control of experimental conditions, so as to prescribe the temperature profile and residence time in the heating chamber. Expanded perlite can thus be produced with various quality specifications for a range of different applications. A mathematical model for perlite grain expansion has been developed, aimed at the detailed investigation and optimization of perlite expansion in the new furnace. The dynamic model consists of ordinary differential equations for both air and particle heat and momentum balances, probing the air temperature distribution as well as the particle velocity, temperature and size along its trajectory in the heating chamber. The effect of raw material physical properties as well as operational parameters on product quality is investigated and discussed.

The flow of goods to Russia has grown faster than the bottleneck can handle and the infrastructure on Finnish eastern borders has been stretched to the limit. The authors choose this topic according to their educational background and the direct and indirect future opportunities that can rise up for everybody by a possible solution. Purpose The main purpose of this thesis was to identify the main reasons for the inefficient border crossing process at the border station in Vaalimaa. The authors will analyse the current situation at the border crossing station in Vaalimaa from two different perspectives: Finnish Customs and Logistics Companies. The authors will propose a possible solution by improving the border crossing process Methodology Qualitative research method is used in order to get the most dependable information for the reasons of the problems. The aim was to get information about the current situation at the border crossing point in Vaalimaa rather than quantitative information. The qualitative research method will allow authors to go deeper inside the topic by interviewing the logistics companies, who are using the route via Finland to Russia and, as well as, Finnish customs and border guards, who are working in Vaalimaa. After the data collection, the authors will propose their own solution for the crossing border problems and they will conclude the research by measuring its validity and reliability. Conclusion The authors will present the main reasons for the inefficient border crossing process, which are bureaucracy, legislation issues, criminality level and poor IT-systems. In order to solve the problem and manage all the possible changes, Russia and EU should have a closely cooperation in any level. The authors after analysing the current situation in Vaalimaa, created the “One-stop” model as an improvement of the whole border crossing process.