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SummaryThe German government has adopted a law that requires sewage plants to go beyond the recovery of phosphorus from wastewater and to promote recycling. We argue that there is no physical global short‐ or mid‐term phosphorus scarcity. However, we also argue that there are legitimate reasons for policies such as those of Germany, including: precaution as a way to ensure future generations’ long‐term supply security, promotion of technologies for closed‐loop economics in a promising stage of technology development, and decrease in the current supply risk with a new resource pool.

Numerous authors have stressed the importance of guaranteeing and protecting the tenure and human rights of indigenous and other forest-based communities under schemes for reducing emissions from deforestation and forest degradation (REDD, or REDD+); and important international indigenous organizations have spoken out strongly against REDD+. This article examines two specific issues that present risks for local communities: rights to forests and rules for resource use. It draws on the findings of a study conducted by the Center for International Forestry Research (CIFOR) on forest tenure reforms in selected countries in Asia, Africa and Latin America from 2006 to 2008. The study underlines the numerous obstacles faced by communities after rights are won, in moving from statutory rights to their implementation and to access to benefits on the ground. It argues that there is currently little reason to expect better results from national policies under REDD+ without binding agreements to protect local rights.

Use of a pilot-scale fixed-film bioreactor was investigated for remediation of bromate contamination within groundwater. Bromate reduction with stoichiometric production of bromide was observed, providing supporting evidence for complete reduction of bromate with no production of stable intermediates. Reduction of 87-90% bromate from an influent concentration of 1.1 mg L(-1) was observed with retention times of 40-80 h. Lower retention times led to decreases in bromate reduction capability, with 11.5% removal at a 10 h retention time. Nitrate reduction of 76-99% from a 30.7 mg L(-1) as NO(3)(-) influent was observed at retention times of 10-80 h, although an increase in nitrite production to 2.7 mg L(-1) occurred with a 10 h retention time. Backwashing was not required, with the large plastic packing media able to accommodate biomass accumulation without decreases in operational efficiency. This study has provided proof of concept and demonstrated the potential of biological bromate reduction by fixed-film processes for remediation of a bromate contaminated groundwater source.

The phosphate (P) fertilizer industry generates a highly hazardous and acidic wastewater. The present study reports the evaluation of an integrated precipitation and Enhanced Biological Phosphorus Removal (EBPR) process for the treatment of fertilizer plant wastewater and effluent detoxification, assessed by microtoxicity and seed germination tests. Effluent samples were collected from a local P fertilizer industry and were characterized by their high fluoride and P content. First, the samples were pre‐treated by precipitation of P and fluoride ions using hydrated lime. The resulting low‐fluoride and phosphorus effluent was then treated with the EBPR process to monitor the simultaneous removal of carbon, nitrogen, and phosphorus. Phosphorus removal included a two‐stage anaerobic/aerobic system operating under continuous flow. Pre‐treated wastewater was added to the activated sludge and operated for 160 days in the reactor. The operating strategy included increasing the organic loading rate from 0.3 to 1.2 g chemical oxygen demand (COD)/L day. The stable and high removal rates of COD, NH4+‐N, and PO43−‐P were then recorded. The mean concentrations of the influent were approximately 3600 mg COD/L, 60 mg N/L and 14 mg P/L, which corresponded to removal efficiencies of approximately 98%, 86%, and 92%, respectively. The microtoxicity of the treated wastewater was then monitored by LUMIStox and its phytotoxicity was investigated on cress, tomato, wheat, maize, ryegrass, and alfalfa seed germination. LUMIStox tests showed that treatment allowed a significant toxicity removal. Moreover, the untreated wastewater inhibited the species germination even when diluted 10 times, whereas a positive effect of treated wastewater was noticed. © 2013 American Institute of Chemical Engineers Environ Prog, 33: 463–471, 2014

Mercury (Hg) represents a growing environmental and health major concern. It originates from natural sources and mainly from anthropogenic processes and it is widely distributed in the natural media. According to the last Global Mercury Assessment (2013), annual global emissions from both sources were estimated to be from 5,000 to 8,000 metric tons per year. Among the different mercury species released to the environment, methylmercury (MeHg) is considered as the most toxic form due to its ability to bioaccumulate, being then threatening even at very low concentrations.Its presence depends onHg(II) bioavailability and global amount.This explains the urgent need to ensure a continuous Hg(II) monitoring. Many efforts have been made in order to develop reliable systems able to deliver quick data and to comply with low detection limits, in accordance with the threshold value delivered by the World Health Organization (1µg L-1/ 5 nM). Spectroscopic techniques such as CV-AFS and CV-AAS are routinely used for Hg(II) determination. Although these methods can afford good sensitivity and low concentrations determination, they require sample preparation step, complex procedures and expensive material, which limits their use for on-site measurements. In this context, electrochemical sensors present excellent candidates for in situ Hg(II) trace analysis, taking in account their numerous advantages compared to spectroscopic techniques: easier handling, simple procedure, low energy consuming, low cost material and portability. In this work, we will propose a new electrochemical approach aiming to conceive and optimize an electrochemical Hg(II) sensor. The method consists in the functionalization of a glassy carbon electrode (GC) with gold nanoparticles (AuNPs) and Diazonium Salts. The main idea is to combine the interesting properties of both AuNPs and Diazonium salts. AuNPs were chosen for their electrocatalytic effect, large surface area, mass transport enhancement and for the strong affinity to mercury which will improve the sensor sensitivity. On the other hand, diazonium salts are used to improve the sensor stability by anchoring the AuNPs to the GC surface. First, nanometricorganic layer were grafted of the polished GC surface, by electrochemical reduction of 1.5 mM4-thiophenol diazonium (SH) using Constant Potential Electrolysis (CPE) in 0.1 M HCl solution at -0.55 V for 300 seconds. Electrochemical characterization performed by Cyclic Voltammetry (CV) and redox probes (ferricyanide and hexaamineruthenium(III)) revealed a total suppression of the signal, confirming the formation of a continuous blocking layer. This was confirmed by Atomic Force Microscopy (AFM)used to estimate the layer thickness, which was found to be 4 nm. Second, AuNPs were electrodeposited, for the first time, onto the diazonium multilayer by CPE in NaNO3 solution containing 0.25 mM HAuCl4for 300 seconds. Once more, redox probes were used to characterize the resulting interface and a total signal restauration and enhancement was observed after AuNPs electrodeposition, which highlights the effective AuNPs onto the organic layers. Field emission gun scanning microscopy (FEG-SEM) was used to provided further evidence and to quantify particle size and density of the AuNPs deposits. Both size and density are dependent on the CPE duration. Small homogeneous AuNPs with 27±3 nm average diameter and 158 NPs/µm2density were observed when the CPE was carried out during 300 seconds, while larger particles with 63±6 nm average diameter and lower density (63 NPs/µm2) were obtained when a longer CPE duration (600 seconds) is used. Finally, AuNPs were activated by cyclic voltammetry in H2SO4 prior to Hg(II) detection in order to homogenize the surface and to rearrange the crystallographic plans of the AuNPs. Herein, the well-known gold oxides reduction peak was observed and used to calculate the electroactive surface area (ESA) of the functionlized electrode. The electrochemical response of the final generated GC/SH/AuNPs interface towards Hg(II) was recorded by Square Wave Anodic Stripping Voltammetry (SWASV) in 0.01 M HCl solution containing different amounts of Hg(II). The SWASV procedure consists on the Hg(II) preconcentration at the electrode surface followed by the preconcentrated Hg(0) reoxidation in Hg(II). Under optimized conditions, and for a preconcentration time of 300 seconds, a well-defined peak, corresponding to Hg(0) reoxidation, was observed around 0.5 V/ECS. The sensor showed a linearity range from 1 up to 10 nM and allowed to reach picomolar level. The stability in HCl, phosphate buffer and air was also studied over several weeks: Once a week, the activation procedure was performed and followed by Hg(II) determination in order to evaluate the analytical performances of the sensor over time. Finally, Hg(II) detection assays were conducted in natural water samples collected from different sampling points. Figure 1

So far, various studies assessed global biomass potentials and came up with widely varying results. Existing potential estimates range from 0 EJ/a up to more than 1,550 EJ/a which corresponds to about three times the current global primary energy consumption. This paper provides an overview of the available research on bioenergy potentials and reviews the different assessments qualitative way with the objective to interpret previous research in an integrated way. In the context of this paper we understand bioenergy as energy from biomass sources including energy crops, residues, byproducts and wastes from agriculture, forestry, food production and waste management. In this review special attention was paid to the difference between residue and energy potentials, land availability estimates, and the geographical resolution of existing potential estimates. The majority of studies concentrate on energy crop potentials retrieved from surplus agricultural land and only few publications assess global potentials separated by different world regions. It results that land allocated to the exclusive production of energy crops varies from 0 to 7,000 ha, depending on land category and scenario assumptions. Only a small number of available potential assessments consider residue potentials as well as energy crop potentials from degraded land. Future energy crop potentials are assumed to vary in the mean from 200 to 600 EJ/yr. In contrast residue potentials are expected to contribute between 62 and 325 EJ/yr. The highest potentials are assigned to Asia, Africa and South America while Europe, North America and the Pacific region contribute minor parts to the global potential.

Abstract The innovation of this research was a holistic approach to the problem of linking the biometric characteristics of six energy plants species and the distribution of moisture along the shoot‘ height and determination of linear models of particle sizes in relation to the moisture. The median biometric parameters values for growth phases I and II were as follows: shoot weight: 63 g and 65 g; stalk weight: 45.1 g and 43.8 g; plant length: 1273 mm and 2157 mm; shoot centre of gravity: 698 mm and 968 mm; slenderness ratio 147 and 215, respectively. For big bluestem and Spartina pectinata the largest values were for slenderness ratio and for phase II amounted to 403 and 410, respectively but most other parameters were the smallest values. Regarding the shoots’ growth, the greatest influence was on the stalks by increasing their lengths more than their diameters. The highest difference in the plant length between harvest terms was observed for Spartina pectinata which increased from 793 mm to 2257 mm (by 185%). The lengths of the Jerusalem artichoke, miscanthus and big bluestem plants also significantly increased: from 1345 mm to 2920 mm (117%), 1214 mm to 2065 mm (70%) and 1064 mm to 1779 mm (67%), respectively. Positive correlation coefficient values between parameters (shoot weight, leaf weight, stalk weight and plant length) indicate that to characterize of plant shoots the shoot mass and plant slenderness could be used. The Rosin-Rammler function fit the chopped plan material size distribution data with an R 2 = 0.909–0.991. All the biomass particle sizes belonged to the “very poorly sorted” category (2.00 mm ≤ σ ig ≤ 4.00 mm), and the particle size distributions were “fine skewed” (0.1 ≤ GS is ≤ 0.3) and “mesokurtic” (0.90 ≤ K gs ≤ 1.11). For grasses relation of particle sizes vs. moisture for phase II (August for Spartina and big bluestem or October for miscanthus) was inverted to phase I (June) with slope coefficients −0.11 and 0.09, respectively. For leaf plants direction of the relation was preserved, wherein for phase II (all plants harvested in October) the growth dynamic was lower than for phase I and slope coefficients of the lines were 0.17 and 0.04, respectively. Moisture content of leafy plants was high, and its distribution along the shoots’ heights was different than that for grasses. Varied values of particle size and weight of plant components, together with the change in moisture along the height of the plants, will impact the diversity of the dynamic loads of elements and working units of forage harvesters and can be useful to explain these results.

ABSTRACTAn overview is given of an International Atomic Energy Agency Coordinated Research Project (CRP) on the treatment of irradiated graphite (i-graphite) to meet acceptance criteria for waste disposal. Graphite is a unique radioactive waste stream, with some quarter-million metric tons worldwide eventually needing to be disposed of. The CRP has involved 24 organizations from 10 Member States. Innovative and conventional methods for i-graphite characterization, retrieval, treatment and conditioning technologies have been explored in the course of this work, and offer a range of options for competent authorities in individual Member States to deploy according to local requirements and regulatory conditions.