Dry anaerobic digestion of organic residues on-farm - a feasibility study

Objectives The feasibility study shall answer the following questions: Are there economical and ecological advantages of on-farm dry digestion biogas plants? How the construction and operation parameters of a dry digestion biogas plant influence environment, profit, and sustainability of on-farm biogas production? The aim of the feasibility study is to provide facts and figures for decision makers in Finland to support the development of the economically and environmentally most promising biogas technology on-farm. The results may encourage on-farm biogas plant manufacturers to develop and market dry anaerobic digestion technology as a complementary technology. This technology may be a competitive alternative for farms using a dry manure chain or even for stockless farms. Results Up to now farm scale dry digestion technology does not offer competitive advantages in biogas production compared to slurry based technology as far as only energy production is concerned. However, the results give an over-view of existing technical solutions of farm-scale dry digestion plants. The results also show that the ideal technical solution is not invented yet. This may be a challenge for farmers and entrepreneurs interested in planning and developing future dry digestion biogas plants on-farm. Development of new dry digestion prototype plants requires appropriate compensation for environmental benefits like closed energy and nutrient circles to improve the economy of biogas production. The prototype in Järna meets the objectives of the project since beside energy a new compost product from the solid fraction was generated. On the other hand the two-phase process consumes much energy and the investment costs are high (>2000 € m-3 reactor volume). Dry digestion on-farm offers the following advantages: Good process stability and reliability, no problems like foam or sedimentation, cheap modules for batch reactors, less reactor capacity, reduced transport costs due to reduced mass transfer in respect of the produced biogas quantity per mass unit, compost of solid digestion residues suitable as fertiliser also outside the farm gate, use of on-farm available technology for filling and discharging the reactor, less process energy for heating because of reduced reactor size, no process energy for stirring, reduced odour emissions, reduced nutrient run off during storage and distribution of residues because there is no liquid mass transfer, suitable for farms using deep litter systems. These advantages are compensated by following constraints: Up to 50% of digestion residues are needed as inoculation material (cattle manure does not need inoculation) requiring more reactor capacity and mixing facilities. Retention time of dry digestion is up to three times longer compared to wet digestion requiring more reactor capacity and more process energy, filling and discharging batch reactors is time and energy consuming. We conclude that only farm specific conditions may be in favour for dry digestion technology. Generally, four factors decide about the economy of biogas production on-farm: Income from waste disposal services, compensation for reduction of greenhouse gas emission, compensation for energy production and - most important for sustainable agriculture - nutrient recycling benefits. Evaluation of the results We did not find any refereed scientific paper that includes a documentation of an on-farm dry digestion biogas plant. It seems that we tried first. We also could not find any results about the biogas potential of oat husks, so we may have found these results first. Farm scale production of anaerobically treated solid manure for composting is new. Dry fermentation biogas plants offer the possibility to design solid manure compost by variation of fermentation process parameters. From different scientific publication databases we found about 10 000 references concerning biogas research during the past 10 years. Less than ten are dealing with biogas reactors for non-liquid substrates on-farm. Recent research mainly concentrates on basic research, biogas process research for communal waste, large-scale biogas plants, and research on laboratory level. This mirrors the fact, that production of research papers is rather financed than product development on site. Our conclusion is that it seems worldwide to be very difficult or even impossible to find financial support for on site research, especially for on-farm prototype biogas reactors. We suppose the following reasons for this fact: biogas plant research requires proficiency in many different scientific disciplines, lack of co-operation between engineering and life sciences, high development costs to transfer basic research results into practical technical solutions, low interest of researchers because on site and on-farm research enjoys low appreciation in terms of scientific credits, portability of farm specific design and process solutions is difficult. Our conclusion is that on site and on-farm research has to be supported by funding agencies if integration of biogas and bio energy into the farm organism is considered as an important target within the agricultural policy framework. Future research on both dry fermentation technique and biogas yield of solid organic residues may close present knowledge gaps. Prototype research may offer competitive alternatives to wet fermentation for farms using a solid manure chain and/or energy crops for biogas production. To encourage farmers and entrepreneurs to foster the development of dry fermentation technology support in terms of education and advisory services is also necessary

The Siting Of Multi-User Inland Intermodal Container Terminals In Transport Networks

Almost without exception, cargo movements by sea have their origins and destinations in the hinterlands and efficient land transport systems are required to support the transport of these cargo to and from the port. Furthermore, not all goods produced are exported or all goods consumed are imported. Those produced and consumed domestically also require efficient transport to move them from their production areas to areas of consumption. The use of trucks for these transport tasks and their disproportionate contribution to urban congestion and harmful emissions has led governments, transport and port authorities and other policy-makers to seek for more efficient and sustainable means of transport. A promising solution to these problems lies in the implementation of intermodal container terminals (IMTs) that interface with both road and rail or possibly inland waterway networks to promote the use of intermodal transport. This raises two important linked questions; where should IMTs be located and what will be their likely usage by individual shippers, each having a choice of whether or not to use the intermodal option. The multi-shipper feature of the problem and the existence of competing alternative modes means the demand for IMTs are outcome of many individual mode choice decisions and the prevailing cargo production and distribution patterns in the study area. This thesis introduces a novel framework underpinned by the principle of entropy maximisation to link mode choice decisions and variable cargo production and distribution problems with facility location problems. The overall model allows both decisions on facility location and usage to be driven by shipper preferences, following from the random utility interpretation of the discrete choice model. Several important properties of the proposed model are presented as propositions including the demonstration of the link between entropy maximisation and welfare maximisation. Exact and heuristic algorithms have been also developed to solve the overall problem. The computational efficiency, solution quality and properties of the heuristic algorithm are presented along with extensive numerical examples. Finally, the implementation of the model, illustration of key model features and use in practice are demonstrated through a case study

Backpacker motivations: a travel career approach

The main purpose of this study was to conceptualize backpacker motivation within the framework of the travel career pattern (TCP) theory of travel motivation. An online survey was administered to backpackers targeted in backpacker-specific online communities in order to obtain a diverse sample. The relationship between backpackers’ previous travel experience and motivations was examined, and six underlying dimensions of motivation were extracted. Four of the motivations, personal/social growth, experiential, budget travel, and independence were found to be fluid in relation to backpackers’ travel experience. Notably, two dimensions, cultural knowledge and relaxation, were found to be constant in relation to the backpackers’ travel experience, which suggest that the two dimensions constitute the core motivations for backpackers

Segmenting the cruise market: an application of multiple correspondence analysis

The cruise line industry is one of the fastest growing travel sectors, and an industry with a high rate of repeat business. This study contributes to the understanding of potential repeat visitors by segmenting cruise tourists based upon their intent to cruise in the future. The purpose of this research note is to reflect on the segmentation method applied. Respondents were asked to respond to questions about their intentions to cruise in the future, and were able to answer yes, no, or not sure, thus making a traditional factor-cluster approach using principal components analysis (or similar) not feasible. This study uses a two step method that combines Multiple Correspondence Analysis (MCA) with a k-means cluster analysis, to segment the sample based on responses to five questions about future cruising intentions

Introduction

The rate of home-ownership across Europe and in many countries has increased significantly in recent decades. This is partly because most governments have promoted home-ownership as part of an asset-based welfare system with the notion that home-ownership will generate wealth for households through the accumulation of housing equity. Changes in house prices play an important role in the generation of the housing equity and the wealth inherent in home-ownership. In general, house prices change in cycles of upward and downward trends. Each of these cycles may be driven by different sets of fundamental determinants and by the prevailing conditions in the wider economy. Over the long term, home-owners usually accumulate significant housing equity, yielding welfare benefits. However, even periods of brief house price decline can erode the value of housing equity accrued over several years. Following the 2007-08 Global Financial Crisis (GFC), for example, the severe decline in house prices caused many recent home-owners to run into negative equity. Figures from Statistics Netherlands show that following the GFC, in the Netherlands alone the total wealth in residential properties declined from e738,449 million in 2009 to e721,018 million by the end of 2012. In effect, home-ownership involves significant financial risk, which can adversely affect the balance sheets of households. These risks require a better understanding and proper measurements. However, it is also important to first understand house price dynamics, which significantly affect the process of equity generation. A thorough understanding of house price dynamics is necessary if we are to identify innovative ways of insuring against the risks associated with home-ownership

Connection men, pushers and migrant trajectories: examining the dynamics of the migration industry in Ghana and along routes into Europe and the Gulf States

This paper examines the inner workings and operational logic of the array of individuals, agencies, state and non-state actors, institutions and social networks that collectively make up the migration industry in Ghana. It sheds light on how actors in the migration industry facilitate and condition migrant mobility, focusing on workers moving from Ghana along two migration corridors towards Europe and the Gulf States for work in the domestic and construction sectors. The study draws on a broad and nuanced conceptualisation of the “migration industry” which goes beyond a narrow focus on actors operating mainly for financial gain. Instead, it focuses on migration not just as a movement from point of departure to arrival, but as a changing journey over both space and time. This allows not only empirical insights into the processes through which people move, but it also provides an analytical lens to better unpack the complexities of migration processes. We extend the analysis of migration industries by incorporating risk theory into the analysis of the migration decision. The decision takes place in a context where migrants’ high level of knowledge about the dangers of migration has not translated into a reduction in migration flows on these two corridors. We analyse migrants’ rationale for choosing to embark on highly risky journeys, even in the face of increasing knowledge about these risks, and to develop appropriate policy responses

A Chaplaincy Training And Support Program To Equip Pastors For Ministry In The South Ghana Conference of Seventh-day Adventist Church

Problem There is currently no Adventist Chaplaincy Ministries capacity development plan to clinically train pastors as chaplains in the South Ghana Conference (SGC) of the Seventh-day Adventist church. This has resulted in the absence of professional chaplains within the denomination in South Ghana. Method I conducted a Chaplaincy Training and Support Program (CTSP) for 15 selected trainees at the South Ghana Church Headquarters Asoredanho-Accra. The Key area of competencies was Clinical Pastoral Education. I employed qualitative method of evaluating trainees by conducting oral and written assessments of data from trainees and ministry recipients. Results As a result of the CTSP, three trainees were identified as chaplains for the hospital, two for prisons, one for the police department, three for tertiary campuses and six for basic schools. The CTSP changed trainees’ mindset of who a chaplain is and they have become ambassadors and disciples of chaplaincy in the Adventist Church in Ghana. Conclusion The CTSP equipped pastors to be chaplains and two out of the 15 trainees have enrolled in a Master’s program in Chaplaincy at Babcock University-Nigeria, and in Guidance and Counseling at the Methodist University-Accra, respectively. The CTSP lessons learned would help fine-tune subsequent possible future chaplaincy academic/competency training at the Valley View University