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The article investigates the feasibility of district heating in a small town adjacent to a Kraft pulp mill in eastern Canada. A detailed heat demand analysis is performed for all buildings using a geographical information system and archived data provided by the municipality. The study shows that the entire space heating requirement of the town can be supplied by steam from the mill, even during exceptional peak demands. A screening test based on load density indicators, however, reveals that a district heating serving the entire town would probably not be economically viable. An economic analysis of partial districts show that a district covering about half of the town can be economically viable with a proper balance between the price of the steam sold by the mill to the district operator and the cost of the energy sold to customers. (Contains 10 tables, 6 figures, and 1 note.)

Due to concerns regarding fossil greenhouse gas emissions, biogenic material such as forest residues is viewed nowadays as a valuable source of carbon atoms to produce syngas that can be used to synthesise biofuels such as methanol. A great challenge in using gasified biomass for methanol production is the large excess of carbon in the syngas, as compared to the H2 content. The water–gas shift (WGS) reaction is often used to add H2 and balance the syngas. CO2 is also produced by this reaction. Some of the CO2 has to be removed from the gaseous mixture, thus decreasing the process carbon yield and maintaining CO2 emissions. The WGS reaction also decreases the overall process heat output. This paper demonstrates the usefulness of using an extra source of renewable H2 from steam electrolysis instead of relying on the WGS reaction, for a much higher performance of syngas production from gasification of wood in a simple system with a fixed-bed gasifier. A commercial process simulation software is employed to predict that this approach will be more efficient (overall energy efficiency of about 67%) and productive (carbon conversion yield of about 75%) than relying on the WGS reaction. The outlook for this process that includes the use of the solid oxide electrolyser technology appears to be very promising because the electrolyser has the dual function of providing all of the supplemental H2 required for syngas balancing and all the O2 required for the production of a suitable hot raw syngas. This process is conducive to biomethanol production in dispersed, small plants using local biomass for end-users from the same geographical area, thus contributing to regional sustainability. [ABSTRACT FROM AUTHOR]

Housing affordability – a long-standing issue for low-income households – is crucial for the flourishing of both households and communities. When housing is unaffordable, households struggle to attain and maintain housing, which negatively effects household well-being. Since the foreclosure crisis, community land trusts (CLTs) have emerged as a viable housing policy. Relying on quantitative and qualitative data collected by a Minneapolis-based CLT, this study examines the experiences of 91 CLT homeowners. Our analysis illustrates how the CLT's institutional framework alters the political, economic, social and material relations that characterize the lives of these households to facilitate the provision of previously unavailable resources. Beyond indefinitely stabilizing households, this new arrangement of relations creates a foundation for the cultivation of ontological security and contributes to the opening up of possibilities and the unfolding of life in ways not previously possible. [ABSTRACT FROM AUTHOR]

This paper focuses on the production of furfural from a simulated kraft dissolving pulp mill pre-hydrolysate solution that is rich in pentoses. Presently, this stream at the mill is mixed with the black liquor and then burned to recover some of the energy needed for the process. However, this pre-hydrolysate would have a higher potential if used as a feedstock for furfural production. This work demonstrates a novel approach to produce furfural in high yields by adding the catalyst only when the desired reaction temperature is reached, and by removing the furfural as soon as it is generated in the reactor. By applying this concept on the pre-hydrolysate, a furfural yield of 76% can be obtained at 240 °C and 2.5 kg m −3 of sulfuric acid. In other approaches where the acid is initially mixed with the pre-hydrolysate, furfural yield varies between 54 and 65% depending on whether furfural is left in the reaction medium or removed as it is formed, respectively. Maximization of furfural production has also been studied in this work by varying the sulfuric acid dosage (1–5 kg m −3 ) and the reactor temperature (160–260 °C). The highest furfural yield of 77.6% can be obtained when a sulfuric acid concentration of 3.6 kg m −3 and a temperature of 240 °C are used for the pre-hydrolysate solution. When lignin is removed from the pre-hydrolysate prior to furfural production, the highest furfural yield is 72.6% at 220 °C and 3.6 kg m −3 of sulfuric acid. [ABSTRACT FROM AUTHOR]