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Space travel, often used by the authors as an equivalent to ‘space tourism’, and outer-space migration should become part of the sustainability discourse – that is the most tempting argument of the...

Abstract Several strategies based on a two steps organosolv pretreatment followed by enzymatic hydrolysis of sugarcane bagasse (SCB) were evaluated with the objective of selecting operational conditions suitable to promote an efficient and low cost production of ethanol. Initially, the influence of six variables used for the organosolv pretreatment was studied. The variables included the time of the first organosolv pretreatment step, the use of 45% ethanol as pulping solution, solid-to-liquid ratio of the ethanol solution used during the first pretreatment step, time of second organosolv pretreatment, concentration of ethanol and concentration of NaOH solution used in the second pretreatment step. Further assays of enzymatic hydrolysis were carried out to promote additional reduction in the costs of the process and improve the results of cellulose conversion to glucose. Eliminating the milling step of the pretreated SCB, using a commercial tensoactive (composed of esters and several surfactants), and recycling 50% of the slurry obtained during the second step of organosolv pretreatment as reaction medium proved to be feasible for use during the enzymatic hydrolysis. Fermentation of the glucose medium produced under the selected pretreatment conditions to ethanol by Saccharomyces cerevisiae occurred with 81% efficiency and a cost of 102.88 $/hL of ethanol.

The large thermal potentials with geothermal gradient of abandoned wells provide the possibility and opportunity for carbon-neutrality transition of district heating systems, whereas energy harvesting from abandoned geothermal wells is full of challenges, due to the considerable initial investment in economic cost, system performance degradation, and so on. In this chapter, a systematic and comprehensive review on the application techniques of abandoned wells is presented, in terms of advanced thermal/power conversions, renewable integrations for district heating, and strategies for performance enhancement. Discussions on real applications have been conducted and future prospects presented, from perspectives of lifetime system performance, techno-economic feasibility analysis, and potential assessment of abandoned wells for carbon-neutrality transition. The results of this chapter can provide preliminary knowledge and cutting-edge technologies on renewable integrations with abandoned wells, so as to demonstrate techno-economic-environmental potentials of abandoned wells and contributions toward carbon-neutrality transition. Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public. Design & Construction Management

Leachate from the source separated organic fraction of municipal solid waste (OFMSW) was evaluated as a substrate for polyhydroxyalkanoates (PHA) production. Initially, the enrichment step was conducted directly on leachate in a feast-famine regime. Maximization of the cellular PHA content of the enriched biomass yielded to low PHA content (29 wt%), suggesting that the selection for PHA-producers was unsuccessful. When the substrate for the enrichment was switched to a synthetic volatile fatty acid (VFA) mixture -resembling the VFA carbon composition of the leachate-the PHA-producers gained the competitive advantage and dominated. Subsequent accumulation with leachate in nutrient excess conditions resulted in a maximum PHA content of 78 wt%. Based on the experimental results, enriching a PHA-producing community in a "clean" VFA stream, and then accumulating PHA from a stream that does not allow for enrichment but does enable a high cellular PHA content, such as OFMSW leachate, makes the overall process much more economically attractive. The estimated overall process yield can be increased four-fold, in comparison to direct use of the complex matrix for both enrichment and accumulation.

Sustainable lignocellulosic spent waste rice straw (SWRS) from bioethanol production inventively applied in this study to valorize petroleum production produced water (PPPW). SWRS expressed efficient pollutant removal over a wide range of petroleum concentration, temperature, pH, salinity, and mixing rate reaching approximately 217 mg/g, within four hours contact time. Kinetic studies revealed a pseudo-second-order chemisorption process with a boundary layer control and 16.97 kJ/mol activation energy where the intra-particle diffusion was not the only rate regulatory step. Thermodynamic studies revealed spontaneous, favorable, and endothermic adsorption, with a strong affinity between the SWRS and oil molecules. Biosorption mechanism studies proved the enrollment of SWRS components' lignin, cellulose, and hemicellulose in the oil uptake with the predominance of chemisorption over physisorption onto the rough and highly porous SWRS surface. A single-stage batch biosorption process was designed based on the best fitted Langmuir adsorption isotherm and applied on a real PPPW sample. The Egyptian standard limits for safe industrial effluents discharge into marine environment with a concomitant decrease in scale formation precursors were achieved recommending its safe reuse for enhanced oil recovery. Finally, for accomplishing zero-waste, SWRS disposed of PPPW treatment substantiated valorized solid biofuel with a sufficient calorific value 38.56 MJ/kg.

In this paper a feasibility study is presented on the application of the advanced control strategy called model predictive control (MPC) as a tool for obtaining improved process operation performance for municipal solid waste (MSW) combustion plants. The paper starts with a discussion of the operational objectives and control of such plants, from which a motivation follows for applying MPC to them. This is followed by a discussion on the basic idea behind this advanced control strategy. After that, an MPC-based combustion control system is proposed aimed at tackling a typical MSW combustion control problem and, using this proposed control system, an assessment is made of the improvement in performance that an MPC-based MSW combustion control system can provide in comparison to conventional MSW combustion control systems. This assessment is based on simulations using an experimentally obtained process and disturbance model of a real-life large-scale MSW combustion plant.

AbstractLife cycle assessment (LCA) aims to provide a near full accounting of impacts from the complete life of a product, to avoid burden shifting between different parts of the life cycle. However, this is exceptionally difficult with transport infrastructure because important parts of their impact lie outside the widely applied industrial‐product‐oriented LCA life stages: production, manufacturing, use, and end of life. To account for those missing impacts, we propose a new framework for assessing the life cycle impacts of transport infrastructure. This framework takes account of the differences between transport infrastructure and the industrial product system to which LCA is most attuned. First, rather than a linear process from material extraction to disposal, this LCA framework accommodates the multiple iterations of transport infrastructure through circular life stages. These reflect the long lifetimes, durability, persistence, and feedback loops of transport infrastructure. Second, this framework recognizes the impact at the start of the life cycle created by demolition of previous infrastructure or land clearing. Third, the tightly linked external impacts that transport infrastructure induces, including influences on travel behavior, local land use, land use, land use change and forestry, and network effects are captured. Fourth, this framework recharacterizes “end of life” as “partial end of life,” in reflection of the widespread reconstruction, major refurbishment of and persistence of indirect impacts from transport infrastructure.

Taking GDP as the standard economic indicator for economic welfare, recent Resources-Economy studies indicate the “dematerialization” of the economy, the so-called decoupling effect. This conclusion seems to alleviate concerns over resource scarcity and limits to growth, and feeds optimism for green growth and sustainability prospects. However, the validity of GDP as the sole and unambiguous measure of the ultimate outcome of the economy has been severely disputed. There is nowadays increasing interest in broader welfare measurements that capture more aspects of economic output and hence constitute better approximations of well-being. The present paper provides an overview of the above discussion and sets out to explore the relevance of three alternative welfare indicators – the Human Development Index (HDI), the Index of Sustainable Economic Welfare (ISEW) and the Genuine Progress Indicator (GPI) – as a basis for evaluating the dependency of welfare and its major engine, the economy, on natural resources. Increasing welfare appears to require a disproportionate use of resources. Strong and increasing dependency on resources at the global level and in giant countries such as China and India may have serious implications for current sustainability policies and the United Nations Sustainable Development Goals.

This is an overview of a Special Issue that has been dedicated to the eighth conference on Process Integration, Modelling and Optimisation for Energy Saving and Pollution Reduction-PRES'05. Six papers from the conference have been selected and peer-reviewed. They cover various subjects of sustainable production and conservation of resources. Advanced integration, life cycle assessment and optimal design are the novel methodologies used. These have been supplemented with case studies dealing with waste activated sludge. © 2006 Elsevier B.V. All rights reserved.