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The common way of handling sludge from pulp and paper (P&P) mill.s wastewater treatment plant (WWTP) is combusting it at the site. Combustion is rather a way to dispose the sludge than take advantage of its energy content. This case study assesses the potential to convert the wet low-value feedstock, specifically WWTP.s secondary sludge, to a more valuable bioenergy product called HTC biocoal through hydrothermal carbonization (HTC) combined with wet oxidation using C-Green.s innovative OxyPower HTC technology. We assess the integration to a Nordic sulphate pulp mill as a retrofit and compare it to baseline scenario of combusting sludge in the recovery boiler. The approach contains assessment of effects of integration to pulp mill.s mass and energy balance, and market, economic and environmental assessments. The results show that the retrofit has positive impacts on the pulp mill.s mass and energy balance, such as reduced evaporator and recovery boiler load. Greenhouse gas emissions reduction of 77% compared to baseline scenario proved the environmental benefits of the retrofit. However, it is challenging to find an economic case for HTC biocoal production in P&P industry due to efficient sludge treatment already taking place. Furthermore, End-of-Waste status is needed before entering the markets. Proceedings of the 29th European Biomass Conference and Exhibition, 26-29 April 2021, Online, pp. 954-960

A general overview on the potentiality of membrane processes in the treatment of aqueous solutions coming from the leather industry is reported. The wet operations of the leather cycle which can be combined with or modified by membrane processes, such as microfiltration, ultrafiltration (UF), nanofiltration (NF) and reverse osmosis, have been described on the basis of consolidated applications and experimental tests on laboratory and industrial pilot scale. Some new applications are also proposed. The membranes and modules employed for the treatment of the effluents, pretreatment of fluids, cleaning procedures and fluid dynamic conditions in experimental applications are reported and discussed. An outline of direct and indirect energy analysis of tanning operations and the results of a mathematical model applied to the degreasing step are also presented. The integrated membrane processes described permit to rationalize the tanning cycle realizing the recovery and the recycle of several chemicals utilized in the tanneries. A reduction of environmental impact, a simplification of cleaning-up processes of wastewaters, an easy re-use of sludges, a decrease of disposal costs, a saving of chemicals and water and of direct and indirect energy are some advantages coming from the described membrane operations. In the future a wider application of the more consolidated membrane processes in this field is expected in the plant innovation phase of a tanning factory.

The process of the biomass gasification in supercritical water has been studied with several different wet biomasses. Sewage sludge was not studied intensively until now, despite the fact that sewage sludge is one of the most abounded waste biomass streams worldwide. This is mainly due to the fact that sewage sludge contains a high amount of inorganic components and there is danger of clogging the reaction system of a continuous flow high pressure high temperature apparatus during reaction. A new developed reaction system in a lab-scale plant enables the effective separation of solids and inorganic components previous to high temperature reaction zone. Main focus of the optimization is the quality of the residual water and the effective separation of the inorganic components of the biomass during the process. Separation of solids enables the recovery of phosphorous, an important topic. Proceedings of the 23rd European Biomass Conference and Exhibition, 1-4 June 2015, Vienna, Austria, pp. 83-87

The gasification of fresh herbage (grass) in supercritical water has been optimized in a lab­scale apparatus and then has been tested in the pilot­plant scale. A high gasification yield is possible. The product gas consists of hydrogen, methane and some short chain hydrocarbons. The pretreatment of fresh herbage is complex. Sand should be removed by washing, size reduction with cutting devices and dilution to less than 10 wt. % DM. An enzymatic treatment at elevated temperatures for 24 h is useful for the subsequent gasification. Optimized process conditions are temperature of 650 °C, pressure of 28 MPa and mean residence time of 2 – 4 min; the resulting gasification yield of 98 % is high, also the hydrogen concentration. CO2 can be removed by a water scrubber at a pressure of 10 – 20 MPa. Due to technical boundaries the reaction temperature in the pilot­plant experiments was lower and consequently the gasification yield was lower. Proceedings of the 18th European Biomass Conference and Exhibition, 3-7 May 2010, Lyon, France, pp. 562-566

Under projected climate changes, runoff and soil erosion processes are likely to become more severe due to the intensification of extreme precipitation events. In consequence of the expected increase of rainfall intensity and erosivity, grass cover is acknowledged as the most effective soil management practice adopted to reduce soil loss by runoff. The aim of this study was to verify the effectiveness of grass cover (GC) in preventing runoff and soil erosion in sloping vineyards with respect to conventional tillage (CT) and to seasonal pattern. Rainfall, runoff and soil loss from experimental farm of Vezzolano (NW-Italy) were recorded in two different periods. Results confirmed the effectiveness of GC, especially when high erosive events occurred in summer, while soil protective effect considerably decreased in autumn, thus pointing out the need to improve appropriate agronomic strategies to achieve better water and soil protection throughout seasons.

The overall objective of the ClimateWater project has been to study European and international adaptation measures and strategies related to climate change impacts and how these are taken into account in water policies. In WP2, "Analysis and synthesis of water related climate change impacts?, several hundred projects and documents were reviewed. Major impact areas are flooding, drought and water scarcity. Flooding and severe droughts are already drastically increasing in Europe. Water supply will be seriously handicapped, in many regions. Water quality will very likely deteriorate as a consequence of climate change. Impacts on agriculture are also severe with very high economic, environmental and social impacts. Major water related/dependent industries such as navigation, hydropower and nuclear power generation will be strongly impacted. Impacts on nature and within this on aquatic ecosystems, terrestrial ecosystems, terrestrial/aquatic ecotones were all identified in details. InWP3 on adaptation measures, strategies are aimed to combat the highly increasing extreme hydrological consequences of climate change, floods and drought. A new concern is the increasing number and severity of floods in Europe with devastating consequences, the extreme flooding of small streams, even of creeks and rivulets. Strategies to fight storm induced sea surges and rising sea water level were also reviewed. The adaptation strategies can be divided into two basic categories: 1) efforts to decrease water consumption by technical measures, pricing policy and by education; 2) measures within water supply including all kinds of storage, through -ecosystem services? with better soil management and other means such as expansion of rainwater harvesting and increased storage capacity by building reservoirs. Strategies to combat climate change induced water pollution pointed to the rising importance of the control of high-runoff induced non-point sources of pollution. In WP4 the identification of research needs, an Index for Impact Magnitude and Action Urgency was developed. The Project Partners identified research needs aimed at bridging the policy gaps, demanded basic changes in all water related policies and much more detailed monitoring of all waters and even regular field studies. A characteristic example is the Water Framework Directive and its main tool the River Basin Management Plans (RBMP). The main conclusions are that research into flood defence, drought combating and ecosystem management strategies must be strengthened. WP5, "Identifying and bridging gaps in water related European policies?, identified that a major gap of the existing water related policies stay on a general level. Some of the major documents of international organisations and larger projects aimed directly at adaptation to climate change also do not give concrete advice. Changes in the policies are often not able to follow the accelerated changes of the climate. To cope with the ever increasing impacts of drought, water pollution and flooding, an enforceable EU-wide regulatory and science based planning of the equitable use of the quantity and quality of water resources will be needed. There are basic underlying misconceptions in some directives (like the Drinking Water Directive). Policies in some cases are simply not existing (Drought, Hydropower and Navigation). The adaptation strategies to bridge the gaps can be divided into the following groups: a) Policy- and decision-making (on national and EU level) in Water Management to create new international legislation that will ensure fair water quality and quantity management. b) Education to adapt to the climate change created situation. c) Designing and implementing the strategies and measures of adaptation, based on field measurements: and this is what we call Ecohydrology. The Co-ordinator's final advice on this basis is to ensure ecohydrological planning of the major tool of RBMP to improve WFD and other policies, and act as rapidly as possible.

The Blueprint to safeguard Europe's water resources underlines vulnerability of water resources as a key concern. This study explores the vulnerability of drinking water (DW) to climate change (CC), to assess the knowledge base and help identify what measures can be taken in this context. The main risks for DW abstraction are competition for use, pollution, floods as well as water scarcity and droughts. Understanding how CC will impact these risks is important to identify measures to be implemented in the future; similarly identifying how much, when and from what sources DW is abstracted will have bearing on the measures to be chosen.

Fuel-only algal systems are not currently economically feasible. Biorefineries which integrate biomass conversion processes and equipment to produce fuels, power and chemicals from biomass, offer a solution. The CO2 microalgae biorefinery (D-Factory) is cultivating strains of Dunaliella in highly saline non-potable waters in photobioreactors and open raceways and applying biorefinery concepts and European innovations in biomass processing technologies to develop a basket of compounds from Dunaliella biomass. Driving down costs by recovering the entire biomass of Dunaliella cells from a saline environment poses one of the many challenges because Dunaliella cells are both motile, and do not possess an external cell wall, making them highly susceptible to cell rupture. In this paper we tackle the problem of harvesting cells intact to recover and process the entire biomass of Dunaliella cells cultivated. Results show a centrifugal g force lower than 5000 g caused little cell disruption, while a g force higher than 9000 g led to ~40% loss of the intact cells and commensurate loss of the intracellular cytosolic marker, glycerol. By contrast using spiral plate technology to harvest the cells recovered >90% of the cells intact. Proceedings of the 22nd European Biomass Conference and Exhibition, 23-26 June 2014, Hamburg, Germany, pp. 360-363

In Mediterranean countries, a large toxic effluents are produced by the agro-industrial activities that have to be disposed, being an environmental problem. On the other hand, due to the high organic load content they can be valorized in terms of energy production. Moreover, because most of them are rich in phenolic compounds (olive mill, cork boiling and chestnut wastewaters), a further valorization may be done to extract valuable biomolecules (bioactive compounds and enzyme) in a biorefinery approach. Aims of the presentation are: a) develop a innovative anaerobic digester, equipped with a monitoring and controlling systems, that will be used to valorize efficiently different phenolic agro-industrial effluents; b) recover valuable molecules with antioxidant and antiradical activity and enzymes, utilizing several novel and eco-friendly extraction systems; c) give solutions, to environmental problems and increase the efficiency and incomes of Mediterranean agro-industrial sector.

Torrefaction, mildly roasting of lignocellulosic biomass, is investigated as a pre-treatment option to acquire a better quality pyrolysis oil. To study the effects of torrefaction on the flash pyrolysis process, measurements were performed using a cyclonic TGA device. The cyclonic TGA can mimic the flash pyrolysis process by virtue of its extremely high heating rates, making it possible to study the kinetics of the reaction. Three streams originating from the same batch of mixed waste wood were studied: raw chips, torrefied chips, and torrefied pellets; the materials were ground to particle sizes of <200, 200-500 and 500-800 µm, and the experiments were performed at temperatures between 475-550°C with sample sizes of 0.5 gram. It was determined that only the smallest particle size range was within the kinetically controlled regime. The results show a lower reaction rate and a higher activation energy for torrefied material compared to raw material, consistent with theory that during torrefaction highly active compounds are released. This means longer reaction times in flash pyrolysis reactors. Furthermore, torrefied pellets react faster than torrefied chips, and adding moisture significantly increases the reaction rate. Proceedings of the 23rd European Biomass Conference and Exhibition, 1-4 June 2015, Vienna, Austria, pp. 1200-1205