[Start-up and Recovery Performance of ANAMMOX Reactors Under Long-term Starvation].

The application of ANAMMOX technology is constrained by sluggish growth and difficulty in enriching ANAMMOX bacteria. Long-term starvation of functioning bacteria due to limited substrate supply makes the steady operation of ANAMMOX reactors more difficult. Re-examining the start-up and recovery performance of the ANAMMOX reactor and identifying its resistance mechanism are important from the standpoint of long-term starvation.

Performance, microbial community and inhibition kinetics of long-term Cu stress on an air-lift nitritation reactor with self-recirculation.

Biological nitrogen removal process could be affected due to the presence of heavy metals owing to their toxicity and accumulation in the sludge. In this study, the impact of Cu shock on a long-term nitritation operation was investigated in an air-lift reactor with self-recirculation. Both the dynamics of microbial community and inhibition kinetics under Cu stress were ascertained.

The long-term effects of hexavalent chromium on anaerobic ammonium oxidation process: Performance inhibition, hexavalent chromium reduction and unexpected nitrite oxidation.

The toxicity of hexavalent chromium (Cr(VI)) is one of the challenges in implementing Anammox process to ammonium-rich wastewater treatment. However, the response of Anammox process to Cr(VI) stress and the inhibition mechanism remain unclear. Here, two Anammox UASB reactors were operated for 285 days under different Cr(VI) stresses.

Insights into the role of extracellular polymeric substances in Zn adsorption in different biological sludge systems.

The adsorption behavior of Zn in four different biological sludge systems, i.e. activated sludge, denitrification sludge, short-cut nitrification sludge, and anammox granules, was investigated.

Designing High-Performance Composite Electrodes for Vanadium Redox Flow Batteries: Experimental and Computational Investigation.

Highly catalytic electrodes play a vital role in exploiting the capability of vanadium redox flow batteries (VRFBs), but they suffer from a tedious synthesis process and ambiguous interaction mechanisms for catalytic sites. Herein, a facile urea pyrolysis process was applied to prepare graphitic carbon nitride-modified graphite felt (GF@CN), and by the virtue of a density functional theory-assisted calculation, the electron-rich pyridinic nitrogen atom of CN granules is demonstrated as the adsorption center for redox species and plays the key role in improving the performance of VRFBs, with 800 cycles and an energy efficiency of 75% at 150 mA cm. Such experimental and computational collaborative investigations guide a realizable and cost-effective solution for other high-power flow batteries.

Co-treatment of flotation waste, neutralization sludge, and arsenic-containing gypsum sludge from copper smelting: solidification/stabilization of arsenic and heavy metals with minimal cement clinker.

Flotation waste of copper slag (FWCS), neutralization sludge (NS), and arsenic-containing gypsum sludge (GS), both of which are difficult to dispose of, are major solid wastes produced by the copper smelting. This study focused on the co-treatment of FWCS, NS, and GS for solidification/stabilization of arsenic and heavy metals with minimal cement clinker. Firstly, the preparation parameters of binder composed of FWCS, NS, and cement clinker were optimized to be FWCS dosage of 40%, NS dosage of 10%, cement clinker dosage of 50%, mill time of 1.

Corrigendum to "Start-Up Characteristics of a Granule-Based Anammox UASB Reactor Seeded with Anaerobic Granular Sludge".

[This corrects the article DOI: 10.1155/2013/396487.].

Utilization of red mud and Pb/Zn smelter waste for the synthesis of a red mud-based cementitious material.

A new method in which Pb/Zn smelter waste containing arsenic and heavy metals (arsenic sludge), red mud and lime are utilized to prepare red mud-based cementitious material (RCM) is proposed in this study. XRD, SEM, FTIR and unconfined compressive strength (UCS) tests were employed to assess the physicochemical properties of RCM. In addition, ettringite and iron oxide-containing ettringite were used to study the hydration mechanism of RCM.

The Potential Use of Vetiveria zizanioides for the Phytoremediation of Antimony, Arsenic and Their Co-Contamination.

Antimony (Sb) and arsenic (As) contaminations are the well reported and alarming issues of various contaminated smelting and mining sites all over the world, especially in China. The present hydroponic study was to assess the capacity of Vetiveria zizanioides for Sb, As and their interactive accumulations. The novelty of the present research is this that the potential of V.

Co-treatment of gypsum sludge and Pb/Zn smelting slag for the solidification of sludge containing arsenic and heavy metals.

Wastewater treatment sludge from a primary lead-zinc smelter is characterized as hazardous waste and requires treatment prior to disposal due to its significant arsenic and heavy metals contents. This study presents a method for the stabilization of arsenic sludge that uses a slag based curing agent composed of smelting slag, cement clinker and limestone. The Unconfined Compressive Strength (UCS) test, the China Standard Leaching Test (CSLT), and the Toxicity Characteristic Leaching Procedures (TCLP) were used to physically and chemically characterize the solidified sludge.

Comparative evaluation of short-term stress of Cd(II), Hg(II), Pb(II), As(III) and Cr(VI) on anammox granules by batch test.

Batch experiments were conducted to investigate the short-term effects of Cd(II), Hg(II), Pb(II), As(III) and Cr(VI) on anammox activity, which are considered to be the top 5 toxic heavy metals in China. The IC values of Cd(II), Hg(II), Pb(II) and Cr(VI) were calculated to be 7.00, 2.

Revegetation of extremely acid mine soils based on aided phytostabilization: A case study from southern China.

Acidification is a major constraint for revegetation of sulphidic metal-contaminated soils, as exemplified by the limited literature reporting the successful phytostabilization of mine soils associated with pH<3 and high acidification potential. In this study, a combination of ameliorants (lime and chicken manure) and five acid-tolerant plant species has been employed in order to establish a self-sustaining vegetation cover on an extremely acid (pH<3) polymetallic pyritic mine waste heap in southern China exhibiting high acidification potential. The results from the first two-year data showed that the addition of the amendments and the establishment of a plant cover were effective in preventing soil acidification.

Enhanced short-cut nitrification in an airlift reactor by CaCO3 attachment on biomass under high bicarbonate condition.

The short-cut nitrification (SCN) performance of an airlift reactor (ALR) was investigated under increasing bicarbonate condition. The sequential increase of bicarbonate from 2.5 to 7.

Biochemical and Metabolic Changes in Arsenic Contaminated Boehmeria nivea L.

Arsenic (As) is identified by the EPA as the third highest toxic inorganic contaminant. Almost every 9th or 10th human in more than 70 countries including mainland China is affected by As. Arsenic along with other toxins not only affects human life but also creates alarming situations such as the deterioration of farm lands and desertion of industrial/mining lands.

Growth, photosynthesis, and defense mechanism of antimony (Sb)-contaminated Boehmeria nivea L.

Ramie (Boehmeria nivea L.) is the oldest cash fiber crop in China and is widely grown in antimony (Sb) mining areas. To evaluate the extent of Sb resistance and tolerance, the growth, tolerance index (TI), Sb content in plant parts and in Hoagland solution, bioaccumulation factor (BF), photosynthesis, and physiological changes in Sb-contaminated B.

Partial nitrification in an air-lift reactor with long-term feeding of increasing ammonium concentrations.

The partial nitrification (PN) performance under high ammonium concentrations was evaluated in an airlift reactor (ALR). The ALR was operated for 253days with stepwise elevation of ammonium concentration to 1400mg/L corresponding nitrogen loading rate of 2.1kg/m(3)/d.

The increasing interest of ANAMMOX research in China: bacteria, process development, and application.

Nitrogen pollution created severe environmental problems and increasingly has become an important issue in China. Since the first discovery of ANAMMOX in the early 1990s, this related technology has become a promising as well as sustainable bioprocess for treating strong nitrogenous wastewater. Many Chinese research groups have concentrated their efforts on the ANAMMOX research including bacteria, process development, and application during the past 20 years.

Depolymerization and decolorization of kraft lignin by bacterium Comamonas sp. B-9.

There is no commercial or industrial-scale process for the remediation of black liquor using microorganisms to date. One of the most important causes is that most microorganisms are not able to use lignin as their principal metabolic carbon or energy source. The bacterial strain Comamonas sp.

Quantitative evaluation of environmental risks of flotation tailings from hydrothermal sulfidation-flotation process.

Floatation tailings (FT) are the main by-products of the hydrothermal sulfidation-flotation process. FT (FT1 and FT2) were obtained by treating two different neutralization sludges (NS) (NS1 and NS2). This paper quantitatively evaluated the environmental risks of heavy metals (Zn, Cd, Cu, Pb, and As) in FT versus NS.

Mathematical modeling of high-rate Anammox UASB reactor based on granular packing patterns.

A novel mathematical model was developed to estimate the volumetric nitrogen conversion rates of a high-rate Anammox UASB reactor based on the packing patterns of granular sludge. A series of relationships among granular packing density, sludge concentration, hydraulic retention time and volumetric conversion rate were constructed to correlate Anammox reactor performance with granular packing patterns. It was suggested that the Anammox granules packed as the equivalent simple cubic pattern in high-rate UASB reactor with packing density of 50-55%, which not only accommodated a high concentration of sludge inside the reactor, but also provided large pore volume, thus prolonging the actual substrate conversion time.

Enhanced remediation of black liquor by activated sludge bioaugmented with a novel exogenous microorganism culture.

Black liquor (BL) is a notoriously difficult wastewater to treat due to the economic and efficiency limitations of physiochemical methods and intrinsic difficulties with bioremediation strategies caused by the high pH (10-13) and lignin content. This study investigated the feasibility of a novel bioaugmentation strategy for BL treatment, which uses a mixed microorganism culture of lignocellulose-degrading microorganisms isolated from degraded bamboo slips. Black liquor treatment was assessed in terms of chemical oxygen demand (COD) and color removal with a sequencing batch reactor organic loading rate of 9 kg COD/L·day under highly alkaline conditions (pH 10).

catena-Poly[[[diaqua-nickel(II)]-μ-pyrazine-2-carboxyl-ato-silver(I)-μ-pyrazine-2-carboxyl-ato] nitrate dihydrate].

In the polymeric complex of the title compound, {[AgNi(C(5)H(3)N(2)O(2))(2)(H(2)O)(2)]NO(3)·2H(2)O}(n), the Ag(I) ion displays an angular coordination geometry with two N atoms from pyrazine-2-carboxyl-ate ligands, and the Ni(II) ion is hexa-coordinated by two O atoms from two water mol-ecules, two O and two N atoms from pyrazine-2-carboxyl-ate ligands in a distorted octa-hedral geometry. In the crystal, the Ag(I) and Ni(II) ions lie on a mirror plane and an inversion centre, respectively. The complex chains, the nitrate ions and the uncoordinated water mol-ecules are linked together through O-H⋯O hydrogen bonds and weak Ag⋯O inter-actions [2.