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Abstract: Black liquor gasification (BLG) for bio-fuel or electricity production at the modern pulp mills is a field in continuous evolution and the efforts are considerably driven by the climate change, fuel security, and renewable energy. This paper evaluates and compares two BLG systems for methanol production: (i) oxygen blown pressurized thermal BLG; and (ii) dry BLG with direct causticization, which have been regarded as the most potential technology candidates for the future deployment. A key objective is to assess integration possibilities of BLG technologies with the reference Kraft pulp mill producing 1000air dried tonnes (ADt) pulp/day replacing conventional recovery cycle. The study was performed to compare the systems’ performance in terms of potential methanol production, energy efficiency, and potential CO2 reductions. The results indicate larger potential of black liquor conversion to methanol from the pressurized BLG system (about 77million tonnes/year of methanol) than the dry BLG system (about 30million tonnes/year of methanol) utilizing identical amount of black liquor available worldwide (220million tDS/year). The potential CO2 emissions reduction from the transport sector is substantially higher in pressurized BLG system (117million tonnes/year CO2 reductions) as compared to dry BLG system (45million tonnes/year CO2 reductions). However, the dry BLG system with direct causticization shows better results when considering consequences of additional biomass import. In addition, comparison of methanol production via BLG with other bio-refinery products, e.g. hydrogen, dimethyl ether (DME) and bio-methane, has also been discussed. [Copyright &y& Elsevier]

This paper reviews climate change impacts on the production, physiology, yield, and product quality of vegetables affected by shifting CO 2 and O 3 concentrations, precipitation and temperature conditions, as well as subjected to extreme weather events. The emphasis is on the temperate cool climate of Western Europe. Physiological processes such as respiration and photosynthesis can acclimate to increasing atmospheric CO 2 and temperatures. The effect of increased CO 2 on vegetables is mostly beneficial for production, but may alter internal product quality, or result in photosynthetic down-regulation. Heat stress reduces fruit set of fruiting vegetables, and speeds up development of determinate vegetables, shortening their time for photoassimilation. In both cases, yield losses result with an impaired product quality, thereby increasing production waste. A longer growing season, arising from warmer temperatures, allows a greater number of plantings to be cultivated, contributing to greater annual yields. However, some vegetables need a period of cold accumulation to produce a harvest. Despite the increasing potential for winter cultivation in the future, perennials like asparagus might increasingly suffer from a lack of winter chilling. In cauliflower, higher temperatures will likely cause insufficient vernalization delaying head induction. This review may contribute in improving the adaptation strategies of vegetable production to climate change for a sustainable horticulture due to an effective risk management by meeting the problems of possible waste increase; breeding of new heat, drought and pest tolerant cultivars; secure water resources; increase the use of renewable energy sources; stimulating new ideas in innovative technologies; development of new approaches to secure stable yields and improve the product quality of vegetables for a cleaner production. © Elsevier. All rights. [ABSTRACT FROM AUTHOR]

Reducing local and global emissions is one of the drivers behind the promotion of renewable energy technologies (RETs). Some RET projects (e.g. solar, marine power, and some biomass and wind) usually require supplemental income from carbon credits in order to make them economically viable. This paper presents the mathematical development of nodal marginal CO 2 emission metrics for hydrothermal systems. These metrics are obtained from optimal power flow and hydrothermal dispatch models considering hydro uncertainty. The proposed model allows a more accurate assessment of the emission reduction effect of RET projects and the provision of efficient carbon signals to the system. Modeling of hydro reservoirs and intertemporal constraints also allows incorporating the emission mitigation potential of water storage. The concepts of marginal CO 2 emissions for hydrothermal systems are first exemplified using a small test system, and then simulations on a real hydrothermal system illustrate how these metrics can inform investment and operational decisions. Theoretical and simulation results show that transmission and hydro storage constraints neglect may provide wrong signals for RET investors, missing the incentives to install in areas where the potential for emissions reduction is higher (where renewable energy displaces a larger amount of coal or diesel). Policy makers can use the proposed model to assess the cost-effectiveness of emission reduction policies. [ABSTRACT FROM AUTHOR]