The intermediate pyrolysis and catalytic steam reforming of brewers spent grain

Brewers spent grain (BSG) is a widely available feedstock representing approximately 85% of the total by-products generated in the brewing industry. This is currently either disposed of to landfill or used as cattle feed due to its high protein content. BSG has received little or no attention as a potential energy resource, but increasing disposal costs and environmental constraints are now prompting the consideration of this. One possibility for the utilisation of BSG for energy is via intermediate pyrolysis to produce gases, vapours and chars. Intermediate pyrolysis is characterised by indirect heating in the absence of oxygen for short solids residence times of a few minutes, at temperatures of 350-450 °C. In the present work BSG has been characterised by chemical, proximate, ultimate and thermo-gravimetric analysis. Intermediate pyrolysis of BSG at 450 °C was carried out using a twin coaxial screw reactor known as Pyroformer to give yields of char 29%, 51% of bio-oil and 19% of permanent gases. The bio-oil liquid was found to separate in to an aqueous phase and organic phase. The organic phase contained viscous compounds that could age over time leading to solid tars that can present problems in CHP application. The quality of the pyrolysis vapour products before quenching can be upgraded to achieve much improved suitability as a fuel by downstream catalytic reforming. A Bench Scale batch pyrolysis reactor has then been used to pyrolyse small samples of BSG under a range of conditions of heating rate and temperature simulating the Pyroformer. A small catalytic reformer has been added downstream of the reactor in which the pyrolysis vapours can be further cracked and reformed. A commercial reforming nickel catalyst was used at 500, 750 and 850 °C at a space velocity about 10,000 L/h with and without the addition of steam. Results are presented for the properties of BSG, and the products of the pyrolysis process both with and without catalytic post-processing. Results indicate that catalytic reforming produced a significant increase in permanent gases mainly (H2 and CO) with H2 content exceeding 50 vol% at higher reforming temperatures. Bio-oil yield decreased significantly as reforming temperature increased with char remaining the same as pyrolysis condition remained unchanged. The process shows an increase in heating value for the product gas ranging between 10.8-25.2 MJ/m as reforming temperature increased. © 2012 Elsevier B.V. All rights reserved.

Linear Fresnel mirror solar concentrator with tracking

Solar energy is the most abundant, widely distributed and clean renewable energy resource. Since the insolation intensity is only in the range of 0.5 - 1.0 kW/m2, solar concentrators are required for attaining temperatures appropriate for medium and high temperature applications. The concentrated energy is transferred through an absorber to a thermal fluid such as air, water or other fluids for various uses. This paper describes design and development of a 'Linear Fresnel Mirror Solar Concentrator' (LFMSC) using long thin strips of mirrors to focus sunlight on to a fixed receiver located at a common focal line. Our LFMSC system comprises a reflector (concentrator), receiver (target) and an innovative solar tracking mechanism. Reflectors are mirror strips, mounted on tubes which are fixed to a base frame. The tubes can be rotated to align the strips to focus solar radiation on the receiver (target). The latter comprises a coated tube carrying water and covered by a glass plate. This is mounted at an elevation of few meters above the horizontal, parallel to the plane of the mirrors. The reflector is oriented along north-south axis. The most difficult task is tracking. This is achieved by single axis tracking using a four bar link mechanism. Thus tracking has been made simple and easy to operate. The LFMSC setup is used for generating steam for a variety of applications. © 2013 The Authors. Published by Elsevier Ltd.

The interaction between master production scheduling and detailed capacity requirements planning : closing the loop in manufacturing resource planning (MRPII) systems

The widespread implementation of Manufacturing Resource Planning (MRPII) systems in this country and abroad and the reported dissatisfaction with their use formed the initial basis of this piece of research which concentrates on the fundamental theory and design of the Closed Loop MRPII system itself. The dissertation concentrates on two key aspects namely; how Master Production Scheduling is carried out in differing business environments and how well the `closing of the loop' operates by checking the capcity requirements of the different levels of plans within an organisation. The main hypothesis which is tested is that in U.K. manufacturing industry, resource checks are either not being carried out satisfactorily or they are not being fed back to the appropriate plan in a timely fashion. The research methodology employed involved initial detailed investigations into Master Scheduling and capacity planning in eight diverse manufacturing companies. This was followed by a nationwide survey of users in 349 companies, a survey of all the major suppliers of Production Management software in the U.K. and an analysis of the facilities offered by current software packages. The main conclusion which is drawn is that the hypothesis is proved in the majority of companies in that only just over 50% of companies are attempting Resource and Capacity Planning and only 20% are successfully feeding back CRP information to `close the loop'. Various causative factors are put forward and remedies are suggested.

Multi-level genetic algorithm for the resource-constrained re-entrant scheduling problem in the flow shop

The re-entrant flow shop scheduling problem (RFSP) is regarded as a NP-hard problem and attracted the attention of both researchers and industry. Current approach attempts to minimize the makespan of RFSP without considering the interdependency between the resource constraints and the re-entrant probability. This paper proposed Multi-level genetic algorithm (GA) by including the co-related re-entrant possibility and production mode in multi-level chromosome encoding. Repair operator is incorporated in the Multi-level genetic algorithm so as to revise the infeasible solution by resolving the resource conflict. With the objective of minimizing the makespan, Multi-level genetic algorithm (GA) is proposed and ANOVA is used to fine tune the parameter setting of GA. The experiment shows that the proposed approach is more effective to find the near-optimal schedule than the simulated annealing algorithm for both small-size problem and large-size problem. © 2013 Published by Elsevier Ltd.

Managing enterprise resource planning projects

Purpose – The purpose of this paper is to help managers to successfully plan, implement, and operate enterprise resource planning (ERP) projects using a risk management framework. Design/methodology/approach – This paper adopted a combined literature review and case study method. Using literature review, the paper first identified major issues of managing ERP projects and develops a risk management framework for managing those issues. The proposed risk management framework was then applied to a ERP implementation project of a UK-based energy services group and its effectiveness for managing ERP projects implementation had been demonstrated. Additionally, the risk factors as identified from the case application are compared with the risk factors from the previous researches so as to suggest mitigating measures. Findings – All the risk factors are categorized into planning, implementation and operations phases along with project processes, organizational transformation and information technology (IT) perspectives. Project implementation phase is the most vulnerable to failure. The case study results reveal that the effect of other projects on on-going ERP project, management of overall IT architecture and non-availability of resources for organizational transformation are most critical from likelihood and impact perspectives. Managing risk across various phases of project and equal emphasize to effective project management, organizational transformation and IT adoption are the key to success in ERP implementation. Practical implications – The risk factors, which were identified using literature review and the case study, have great significance as mitigating measures of those risks may result successful implementation of ERP projects in the industry. Additionally, proposed risk management framework could be customized to implement ERP projects elsewhere. Originality/value – ERP projects are risky as they are capital intensive, technically complex, and call for organizational transformation. There are both success and failure stories. However, both researchers and practitioners agree, that if it can be implemented and operated successfully and benefits should be achievable. Although there are many studies on ERP implementation, little has been discussed on managing risks of ERP projects. Therefore, this paper bridges the gap.

Risk management in enterprise resource planning implementation:a new risk assessment framework

Enterprise resource planning (ERP) projects are risky. But if they are implemented appropriately, they can provide competitive advantage to organisations. Therefore, ERP implementation has become one of the most critical aspects of today's information management research. The main purpose of this article is to describe a new ERP risk assessment framework (RAF) that can be used to increase the success of ERP implementation. In this article, through a case study based in a leading UK-based energy service provider, we demonstrate the new RAF, which has been shown to help identify and mitigate risks in ERP implementation. In contrast to other research, this RAF identifies risks hierarchically in external engagement, programme management, work stream and work package levels across technical, schedule, operational, business and organisational categories. This not only helped to develop responses to mitigate risks but also facilitates on-going risk control.

Adaptive resource allocation for QoE-aware mobile communication networks

A real-time adaptive resource allocation algorithm considering the end user's Quality of Experience (QoE) in the context of video streaming service is presented in this work. An objective no-reference quality metric, namely Pause Intensity (PI), is used to control the priority of resource allocation to users during the scheduling process. An online adjustment has been introduced to adaptively set the scheduler's parameter and maintain a desired trade-off between fairness and efficiency. The correlation between the data rates (i.e. video code rates) demanded by users and the data rates allocated by the scheduler is taken into account as well. The final allocated rates are determined based on the channel status, the distribution of PI values among users, and the scheduling policy adopted. Furthermore, since the user's capability varies as the environment conditions change, the rate adaptation mechanism for video streaming is considered and its interaction with the scheduling process under the same PI metric is studied. The feasibility of implementing this algorithm is examined and the result is compared with the most commonly existing scheduling methods.

Quality-driven resource utilization methods for video streaming in wireless communication networks

This research is focused on the optimisation of resource utilisation in wireless mobile networks with the consideration of the users’ experienced quality of video streaming services. The study specifically considers the new generation of mobile communication networks, i.e. 4G-LTE, as the main research context. The background study provides an overview of the main properties of the relevant technologies investigated. These include video streaming protocols and networks, video service quality assessment methods, the infrastructure and related functionalities of LTE, and resource allocation algorithms in mobile communication systems. A mathematical model based on an objective and no-reference quality assessment metric for video streaming, namely Pause Intensity, is developed in this work for the evaluation of the continuity of streaming services. The analytical model is verified by extensive simulation and subjective testing on the joint impairment effects of the pause duration and pause frequency. Various types of the video contents and different levels of the impairments have been used in the process of validation tests. It has been shown that Pause Intensity is closely correlated with the subjective quality measurement in terms of the Mean Opinion Score and this correlation property is content independent. Based on the Pause Intensity metric, an optimised resource allocation approach is proposed for the given user requirements, communication system specifications and network performances. This approach concerns both system efficiency and fairness when establishing appropriate resource allocation algorithms, together with the consideration of the correlation between the required and allocated data rates per user. Pause Intensity plays a key role here, representing the required level of Quality of Experience (QoE) to ensure the best balance between system efficiency and fairness. The 3GPP Long Term Evolution (LTE) system is used as the main application environment where the proposed research framework is examined and the results are compared with existing scheduling methods on the achievable fairness, efficiency and correlation. Adaptive video streaming technologies are also investigated and combined with our initiatives on determining the distribution of QoE performance across the network. The resulting scheduling process is controlled through the prioritization of users by considering their perceived quality for the services received. Meanwhile, a trade-off between fairness and efficiency is maintained through an online adjustment of the scheduler’s parameters. Furthermore, Pause Intensity is applied to act as a regulator to realise the rate adaptation function during the end user’s playback of the adaptive streaming service. The adaptive rates under various channel conditions and the shape of the QoE distribution amongst the users for different scheduling policies have been demonstrated in the context of LTE. Finally, the work for interworking between mobile communication system at the macro-cell level and the different deployments of WiFi technologies throughout the macro-cell is presented. A QoEdriven approach is proposed to analyse the offloading mechanism of the user’s data (e.g. video traffic) while the new rate distribution algorithm reshapes the network capacity across the macrocell. The scheduling policy derived is used to regulate the performance of the resource allocation across the fair-efficient spectrum. The associated offloading mechanism can properly control the number of the users within the coverages of the macro-cell base station and each of the WiFi access points involved. The performance of the non-seamless and user-controlled mobile traffic offloading (through the mobile WiFi devices) has been evaluated and compared with that of the standard operator-controlled WiFi hotspots.

A new scheduling method for enhanced quality of experience in LTE systems

In this paper a new approach to the resource allocation and scheduling mechanism that reflects the effect of user's Quality of Experience is presented. The proposed scheduling algorithm is examined in the context of 3GPP Long Term Evolution (LTE) system. Pause Intensity (PI) as an objective and no-reference quality assessment metric is employed to represent user's satisfaction in the scheduler of eNodeB. PI is in fact a measurement of discontinuity in the service. The performance of the scheduling method proposed is compared with two extreme cases: maxCI and Round Robin scheduling schemes which correspond to the efficiency and fairness oriented mechanisms, respectively. Our work reveals that the proposed method is able to perform between fairness and efficiency requirements, in favor of higher satisfaction for the users to the desired level. © VDE VERLAG GMBH.

Expanding the biomass resource:sustainable oil production via fast pyrolysis of low input high diversity biomass and the potential integration of thermochemical and biological conversion routes

Waste biomass is generated during the conservation management of semi-natural habitats, and represents an unused resource and potential bioenergy feedstock that does not compete with food production. Thermogravimetric analysis was used to characterise a representative range of biomass generated during conservation management in Wales. Of the biomass types assessed, those dominated by rush (Juncus effuses) and bracken (Pteridium aquilinum) exhibited the highest and lowest volatile compositions respectively and were selected for bench scale conversion via fast pyrolysis. Each biomass type was ensiled and a sub-sample of silage was washed and pressed. Demineralization of conservation biomass through washing and pressing was associated with higher oil yields following fast pyrolysis. The oil yields were within the published range established for the dedicated energy crops miscanthus and willow. In order to examine the potential a multiple output energy system was developed with gross power production estimates following valorisation of the press fluid, char and oil. If used in multi fuel industrial burners the char and oil alone would displace 3.9 × 105 tonnes per year of No. 2 light oil using Welsh biomass from conservation management. Bioenergy and product development using these feedstocks could simultaneously support biodiversity management and displace fossil fuels, thereby reducing GHG emissions. Gross power generation predictions show good potential.