Treatment Of Waste Liquor Research Articles

Kinetic and isotherm of competitive adsorption cadmium and lead onto Saccharomyces cerevisiae autoclaved cells.

Heavy metal pollution has been regarded as a significant public health hazard during the industrialization, which also have exhibited various types of toxicological manifestations. Moreover, due to the high cost and toxic by-products, some conventional remediation methods were limited to heavy metals pollution control. In this work, autoclaved Saccharomyces cerevisiae was used as a biosorbent for the removal of Cd2+ and Pb2+ from single and binary ions aqueous solution system. The kinetics and isotherm of Cd2+ and Pb2+ were studied in different ion systems. The results showed that the competitive adsorption ability of S. cerevisiae to Pb2+ was stronger than that to Cd2+ in binary ions solution. To all the single ion solution of Cd2+ or Pb2+ and binary ions solution of Cd2+-Pb2+, there always existed that the adsorption of metal ions on S. cerevisiae fitted well with pseudo-second-order kinetic model and Langmuir isotherms model. The adsorption quantity qt in different solutions followed the sequence as qt (Cd2+-Pb2+) > qt (Pb2+-single) > qt (Pb2+-binary) > qt (Cd2+-single) > qt (Cd2+-binary). The autoclaved S. cerevisiae used in this research was one kind of rapid and favourable biosorbent for Pb2+ and Cd2+. In Pb2+ and Cd2+-containing solutions, sites competition and jointed toxicity of Pb2+ and Cd2+ on S. cerevisiae cells were the key to the total adsorption effect, and further researches were necessary in the next work. Thus, the current research presented that the autoclaved S. cerevisiae could be applied as an effective biosorbent for heavy metal adsorption from water environment and the design of eco-friendly technologies for the treatment of waste liquor.

Biosorption of nickel, cobalt, zinc and copper ions by Serratia marcescens strain 16 in mono and multimetallic systems

The metallurgical industry is one of the main sources of heavy metal pollution, which represents a severe threat to life. Metals can be removed from aqueous solutions by using microbial biomasses. This paper analyses the heavy metal biosorption capacity of Serratia marcescens strain 16 in single and multimetallic systems. The results obtained show that Co(II), Ni(II) and Zn(II) biosorption in monometallic systems is two to three times higher than in the presence of bi-metallic and multimetallic solutions. Fourier transform infrared spectroscopy confirmed that carbonyl, carboxyl and hydroxyl were the main functional groups, as well as the amide bands I and II involved in metal uptake, which are present in external structures of the bacterial cell. The results obtained demonstrated the viability of S. marcescens strain 16 as a biosorbent for the design of eco-friendly technologies for the treatment of waste liquor.

One-pot green extraction of high charge density cellulose nanocrystals with high yield for bionanocomposites

The use of lignocellulosic materials for extracting functionalized cellulose nanocrystals (FCNs) in a green and sustainable method under mild conditions is limited owing to the strong hydrogen bonding in cellulose. A facile, green, and high-efficient avenue was developed to produce FCNs with high yield through the mechanochemistry synergetic effect of recyclable p-toluenesulfonic acid (PTSA)-catalyzed deep eutectic solvent (PDES) and microwave- solvothermal (MWS). FCNs with a high charge density of 1.59 e nm−2, a crystallinity of 81%, a better thermostability and dispersibility were obtained at a high yield of 87.6% by the one-step processing. The PDES could be easily recycled, and thus was beneficial to cost reduction and waste liquor treatment. Generated FCNs could be used to develop functional bionanocomposites due to their enhanced effect. When a loading of 1 wt% FCNs was added into gelatin matrix, the tensile strength and Young’s modulus of the bionanocomposites increased 188 and 131%, respectively, suggesting their remarkable stress transfer potential. Thus, the study demonstrates a green and cost-effective approach for the mass production of FCNs, contributing to strong potential in building high-performance bionanocomposites.

Facile One-step Fabrication of Functional Cellulose Nanocrystals with High Efficiency under Microwave-ultrasound Synergy

The use of cellulosic biomass for the manufacture of functional cellulose nanocrystals (FCNs) in a mild and green process is limited due to the multiple hydrogen bonds between cellulose. Based on the mechanochemical mechanism, an efficient and green approach to cleave hydrogen bonds and fabricate FCNs was realized via microwave-ultrasound synergy. In the one-step process, impact force, crash force, friction, chemical action, and thermodynamic interaction combined to create synergistic effects, accelerating the cleavage of hydrogen bonds and formation of FCNs synchronously. One-step purification of FCNs was implemented after reaction for the recovery of byproducts, which was critical to cost reduction and waste liquor treatment. FCNs with high crystallinity of 80%, high charge density, and good dispersion stability were obtained. Thus, a facile versatile green avenue for the large-scale production of FCNs was achieved in the study, and is expected to carry significant benefits in terms of economy and sustainability.

A Laboratory Simulation Research Method for Speciation Distribution of Ultratrace Pu in Groundwater and Its Application

The migration rate difference of various Pu species in contaminated groundwater can be up to 3 orders of magnitude. Accurately obtaining speciation distribution of Pu is the first problem to be solved in site safety assessment. However, the in-situ chemical properties of groundwater are easily affected by the external environment, and Pu content in the contaminated groundwater is usually at ultra-trace level, the existing sampling-laboratory analysis method cannot directly determine the speciation distribution of Pu. Here a laboratory simulation research method for speciation distribution of ultratrace Pu in groundwater was established, in which a nitrogen assisted sampling and storage device was designed and employed to sample groundwater, and the groundwater sample was transported and kept in Anaerobic Glove Box, into which spiked Pu was added and the speciation distribution of Pu were monitored at various aging time by series speciation analysis techniques we improved and integrated. Using the method, the in-situ chemical properties of groundwater are well maintained, and the speciation distribution of ultratrace Pu in a contaminated groundwater from a granite area, NW China was obtained successfully. The results were basically consistent with the modelling results by geochemical software and/or analysis results by related instruments. Not only the method can continuously be used in the field of speciation distribution of Pu in contaminated water, but also can be used in other fields such as the treatment of waste liquor from Nuclear Plant, Reactor study, and so on.

Complex Process Monitoring Using KUCA With Application to Treatment of Waste Liquor

In this paper, a new nonlinear process modeling method called kernel uncorrelated component analysis (KUCA) is proposed. Several advantages of KUCA are summarized as follows. First, KUCA is superior to traditional data-driven modeling methods such as principal component analysis, independent component analysis, and so on, for it has no constraints on data distribution and data structure. In other word, it can be applied to modeling non-Gaussian and nonlinear process. Second, the proposed KUCA allows us to extract uncorrelated components (UCs) from observations directly without considering the second-order or higher order statistic, which is of low computational load. In addition, KUCA is applied to a numerical example to evaluate its performance of source signal separation. Finally, on the basis of KUCA, the corresponding processes monitoring scheme is developed, and the hot galvanizing pickling waste liquor treatment process is taken to evaluate the monitoring performance of the proposed methods. Experiment results demonstrate the feasibility of the proposed monitoring scheme.

Application of independent component analysis with semi‐supervised Laplacian regularization kernel density estimation

AbstractIn this study, fault detection and fault reconstruction methods are developed using matrix factorization of component vectors obtained with independent component analysis (ICA). Two monitoring statistics are used for fault detection in a detailed analysis of the ICA data model. A fault reconstruction technique is proposed that can determine the normal value and an estimate of the fault magnitude from the measurements. A semi‐supervised Laplacian regularization (SLR) kernel density estimation approach is introduced to determine the normal operating region, which can significantly reduce the false alarm rate. These methods are applied to a hot galvanizing pickling waste liquor treatment process (HGPWLTP) to evaluate the performance of the proposed approach. The test results show that the proposed approach has satisfactory performance.

Uncorrelated component analysis on manifold for statistical process monitoring

A novel process modeling approach referred to as locally invariant uncorrelated component analysis (LIUCA) is proposed for the purpose of statistical process monitoring. The contributions are as follows: (1) LIUCA intends to find a part‐based representation subspace in which two data points are close to each other, if they are close in the k‐nearest neighbor graph; (2) LIUCA can exploit the geometrical structure of the data space, which will improve the algorithm's modeling performance in real‐world applications; (3) LIUCA‐based multivariate statistical process monitoring scheme is proposed. (4) In contrast to traditional process modeling algorithm such as principal component analysis, LIUCA imposes no restriction on data distribution. In addition, both a multivariate numerical example and a hot galvanizing pickling waste liquor treatment process are taken to evaluate the feasibility of the proposed process monitoring scheme. Experiment results demonstrate the effectiveness of the proposed method.

Municipal waste liquor treatment via bioelectrochemical and fermentation (H2 + CH4) processes: Assessment of various technological sequences

In this paper, the anaerobic treatment of a high organic-strength wastewater-type feedstock, referred as the liquid fraction of pressed municipal solid waste (LPW) was studied for energy recovery and organic matter removal. The processes investigated were (i) dark fermentation to produce biohydrogen, (ii) anaerobic digestion for biogas formation and (iii) microbial fuel cells for electrical energy generation. To find a feasible alternative for LPW treatment (meeting the two-fold aims given above), various one- as well as multi-stage processes were tested. The applications were evaluated based on their (i) COD removal efficiencies and (ii) specific energy gain. As a result, considering the former aspect, the single-stage processes could be ranked as: microbial fuel cell (92.4%)> anaerobic digestion (50.2%)> hydrogen fermentation (8.8%). From the latter standpoint, an order of hydrogen fermentation (2277 J g−1 CODremoved d−1)> anaerobic digestion (205 J g−1 CODremoved d−1)> microbial fuel cell (0.43 J g−1 CODremoved d−1) was attained. The assessment showed that combined, multi-step treatment was necessary to simultaneously achieve efficient organic matter removal and energy recovery from LPW. Therefore, a three-stage system (hydrogen fermentation-biomethanation-bioelectrochemical cell in sequence) was suggested. The different approaches were characterized via the estimation of COD balance, as well.

Semi‐supervised kernel partial least squares fault detection and identification approach with application to HGPWLTP

AbstractIn this paper, fault detection and identification methods based on semi‐supervised Laplacian regularization kernel partial least squares (LRKPLS) are proposed. In Laplacian regularization learning framework, unlabeled and labeled samples are used to improve estimate of data manifold so that one can establish a more robust data model. We show that LRKPLS can avoid the over‐fitting problem which may be caused by sample insufficient and outliers present. Moreover, the proposed LRKPLS approach has no special restriction on data distribution, in other words, it can be used in the case of nonlinear or non‐Gaussian data. On the basis of LRKPLS, corresponding fault detection and identification methods are proposed. Those methods are used to monitor a numerical example and Hot Galvanizing Pickling Waste Liquor Treatment Process (HGPWLTP), and the cases study show effeteness of the proposed approaches. Copyright © 2016 John Wiley & Sons, Ltd.

Study of a hybrid process combining PACs and membrane operations for antibiotic wastewater treatment

An integrated process combining powdered activated carbons (PACs) with ultrafiltration (UF) and reverse osmosis (RO) was studied for the treatment of waste liquor coming from tetracycline (TC) production. The aim was to purify water and to recover the TC present in the waste stream. Using RO alone, results showed that the concentration of COD and TC in the permeate could be reduced from about 8000 mg.L −1 to less than 200 mg.L −1 and from 850 mg.L −1 to 70 mg.L −1, respectively. However, irreversible fouling occurred that dramatically shortened the lifetime of RO operation. The integration of UF with RO showed that UF could reduce COD from about 8000 mg.L −1 in the feed to 3600 mg.L −1 in the permeate without an effect on TC concentration. The fouling in the RO was reduced, and in addition it could be recovered by a backflushing operation. Experimental results showed that TC recovery efficiency and purity were improved with UF pretreatment. Further studies indicated that the UF–RO performance was improved by addition of PACs to the waste liquor; the optimized amount of PACs was 8.0 mg.L −1, which showed that the permeate flux of RO maintained a high value even when the volume reduction coefficient was up to 3.5. The water collected from RO permeate was significantly purified (TOC = 56 mg·mL −1; COD = 98 mg·mL −1; TC = 46 mg·mL −1) compared to the initial feed solution (TOC = 3200 mg·mL −1; COD = 8000 mg·mL −1; TC = 850 mg·mL −1). The TC present in the RO retentate was recovered by precipitation. The TC recovery efficiency and purity were 72.0% and 88.0%, respectively. The results showed that integrated PACs–UF–RO combined with precipitation can be a promising method to treat the wastewater and recover TC.

99/03237 Method and device for treatment of waste liquor, obtained during digestion of wood, by gasification for use in wood digestion

99/03237 Method and device for treatment of waste liquor, obtained during digestion of wood, by gasification for use in wood digestion

クラフトパルプ廃液の電解酸化処理

As an effective treatment of waste liquor from the kraft pulping process, its electrolytic oxidation has been attempted. The waste liquor used in electrolytic experiment was diluted to a concentration of about 1%. The reactivity of lignin in the waste liquor was estimated from the oxidative reaction of the purified thiolignin. To examine the oxidating ability of electrode, platinum, stainless steel and lead-dioxide plates were used as the electrode. The values of COD and absorbances at 280 and 500 nm of the waste liquor after the electrolysis decreased according to the following order of electrodes : lead dioxide stainless steel platinum. From this result, using the lead-dioxide electrode, the controlled-current electrolysis was made at 300 and 600 mA in the range of 10 to 80°C.The effect of electrolytic oxidation on the waste liquor was evaluted by measurements of COD and absorbance of the liquor. The high current density was effective for the treatment of the waste liquor at temperatures above 60°C, whereas the low current density was effective at temperatures below 30°C. The most satisfactory result was obtained at 60°C and 600 mA.

活性汚泥による臭気排水の脱臭操業経験

In the conventional deodorization of kraft waste liquor, so-called physico-chemical processes, such as absorption, adsorption, incineration, etc., have been widely used.We have developed a biological deodorization process making use of the mill's existing activated sludge process.Based on present research achievement, Shirakawa Mill has modified the 8, 100m3 capacity activated sludge process and achieved successfully the deodorization at efficiency of 90% or higher.In a kraft pulping mill which has already installed activated sludge process, deodorization can be accomplished by making use of present technology while maintaining fully the capability of the waste liquor treatment.

硫酸焼鉱の脱銅焙焼と浸出 (第1報)

For obtaining iron blast furnace charge by dilute acid leaching process from pyrite cinder, the containing Cu2S and CuO·Fe2O3must be converted into CuO and CuSO4. FeSO4only, or mixed with NaCl was aimed to utilize as reaction reagent in low temperature roasting of pyrite cinder for this purpose.FeSO4, by-product from waste liquor treatment in Titan White plant etc., is considered a kind of non-utilized resource.In this report, reactivity of FeSO4was investigated for knowing posibility of the new trial. By thermodynamical calculation, it was clarified that FeSO4is able to convert Cu2S, CuO·Fe2O3and ZnO·Fe2O3to the sulfate. Experiments in stream of air and N2showed the same results. In mixed with NaCl, the more reactivity was observed, besides in the case of Cu2S in N2. Also, in heating of FeSO4, the decomposition state, mutual reaction with NaCl and the degree of melting tendency were investigated. From these Tesults, the reaction mechanism was estimated.

メッキ廃液処理におよぼす各種金属イオンの影響

メッキ廃液処理におよぼす各種金属イオンの影響

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パルプ製紙工場の廃水処理(水処理小特集)

パルプ製紙工場の廃水処理(<小特集>水処理小特集)