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Hydrogen sulfide (H 2 S) is an environmental pollutant, and also the major released gas during the decay of meat products. To protect the ecological environment and human health, the establishment of a swift, convenient, and accurate detection method for H 2 S becomes essential. However, existing methods are still suffering from complex synthesis, high toxicity, poor visualization, and high detection limit. Herein, Au NCs-CDs nanocomposite-based test paper and polyvinyl alcohol (PVA) film are combined with a smartphone for sensitive and specific sulfide visualized monitoring. After the addition of sulfide, the fluorescence color changes from orange to green, achieving a quantitative linearity towards sulfide from 5 nM to 30 μM, with a low detection limit of 4.20 nM. The proposed method shows practicability in natural water samples. Furthermore, distinct fluorescence color variation is shown towards H 2 S originating from spoiled meat, showing the potential application prospect of Au NCs-CDs-PVA film as a meat freshness detector., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Copyright of China Pulp & Paper is the property of China Pulp & Paper Magazines Publisher and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Reduction of water pollutant emissions and energy consumption is regarded as a key environmental objective for the pulp and paper industry. The paper develops a bottom-up model called the Industrial Water Pollutant Control and Technology Policy (IWPCTP) based on an industrial technology simulation system and multiconstraint technological optimization. Five policy scenarios covering the business as usual (BAU) scenario, the structural adjustment (SA) scenario, the cleaner technology promotion (CT) scenario, the end-treatment of pollutants (EOP) scenario, and the coupling measures (CM) scenario have been set to describe future policy measures related to the development of the pulp and paper industry from 2010-2020. The outcome of this study indicates that the energy saving amount under the CT scenario is the largest, while that under the SA scenario is the smallest. Under the CT scenario, savings by 2020 include 70 kt/year of chemical oxygen demand (COD) emission reductions and savings of 7443 kt of standard coal, 539.7 ton/year of ammonia nitrogen (NH4-N) emission reductions, and savings of 7444 kt of standard coal. Taking emission reductions, energy savings, and cost-benefit into consideration, cleaner technologies like highly efficient pulp washing, dry and wet feedstock preparation, and horizontal continuous cooking, medium and high consistency pulping and wood dry feedstock preparation are recommended.

To evaluate the reduction potential of industrial water pollutant emissions and to study the application of technology simulation in pollutant control and environment management, an Industrial Reduction Potential Analysis and Environment Management (IRPAEM) model was developed based on coupling of "material-process-technology-product". The model integrated bottom-up modeling and scenario analysis method, and was applied to China's paper industry. Results showed that under CM scenario, the reduction potentials of waster water, COD and ammonia nitrogen would reach 7 x 10(8) t, 39 x 10(4) t and 0.3 x 10(4) t, respectively in 2015, 13.8 x 10(8) t, 56 x 10(4) t and 0.5 x 10(4) t, respectively in 2020. Strengthening the end-treatment would still be the key method to reduce emissions during 2010-2020, while the reduction effect of structure adjustment would be more obvious during 2015-2020. Pollution production could basically reach the domestic or international advanced level of clean production in 2015 and 2020; the index of wastewater and ammonia nitrogen would basically meet the emission standards in 2015 and 2020 while COD would not.

The increase in anthropogenic pollution raises serious concerns regarding contamination of water bodies and aquatic species with potential implications on human health. Pharmaceutical compounds are a type of contaminants of emerging concern that are increasingly consumed and, thus, being frequently found in the aquatic environment. In this sense, an electrochemical sensor based on an unmodified and untreated carbon fiber paper (CPS—carbon paper sensor) was simply employed for the analysis of trimethoprim antibiotic in fish samples. First, the analytical conditions were thoroughly optimized in order for the CPS to achieve maximum performance in trimethoprim determination. Therefore, an electrolyte (0.1 M Britton–Robinson buffer) pH of 7 was selected and for square wave voltammetry parameters, optimum values of amplitude, frequency and step potential corresponded to 0.02 V, 50 Hz, and 0.015 V, respectively, whereas the deposition of analyte occurred at +0.7 V for 60 s. In these optimum conditions, the obtained liner range (0.05 to 2 µM), sensitivity (48.8 µA µM−1 cm−2), and LOD (0.065 µM) competes favorably with the commonly used GCE-based sensors or BDD electrodes that employ nanostructuration or are more expensive. The CPS was then applied for trimethoprim determination in fish samples after employing a solid phase extraction procedure based on QuEChERS salts, resulting in recoveries of 105.9 ± 1.8% by the standard addition method. [ABSTRACT FROM AUTHOR]

The chemical oxygen demand (COD) emissions from the pulp and paper industry in China have declined continuously since the tighter COD discharge standards were implemented in 2008. Using firm-level data from 2003 to 2013, we investigate how China's pulp and paper firms would respond to the tighter COD discharge standards with a difference-in-differences design. We find that the tighter COD discharge standards have significant causal effects to induce the pulp and paper firms to reduce their COD emissions primarily through adopting cleaner production. However, the effectiveness of the tighter COD discharge standards depends on monitoring and enforcement activities as well as other regulations accompanying with the tighter COD discharge standards, all of which have become strengthened since China's 11th Five-Year-Plan (FYP, 2006–2010). While strengthened environmental regulations since the 11th FYP are from the top leadership of the Chinese government in order to deal with the increasing environmental degradation, the underlying driving force of the strengthened environmental regulations is from the household demand for better environmental quality as income increases. This study enriches literature not only on firms' responses to environmental regulations in developing countries but also on environmental regulations and technology adoption as well as environmental enforcement and compliance. [ABSTRACT FROM AUTHOR]

The paper-making process can produce large amounts of wastewater (WW) with high particulate and dissolved organic loads. Generally, in developed countries, stringent international regulations for environmental protection require pulp and paper mill WW to be treated to reduce the organic load prior to discharge into the receiving environment. This can be achieved by primary and secondary treatments involving both chemical and biological processes. These processes result in complex changes in the nature of the organic material, as some components are mineralised and others are transformed. In this study, changes in the nature of organics through different stages of secondary treatment of pulp and paper mill WW were followed using three advanced characterisation techniques: solid-state (13)C nuclear magnetic resonance (NMR) spectroscopy, pyrolysis-gas chromatography mass spectrometry (py-GCMS) and high-performance size-exclusion chromatography (HPSEC). Each technique provided a different perspective on the changes that occurred. To compare the different chemical perspectives in terms of the degree of similarity/difference between samples, we employed non-metric multidimensional scaling. Results indicate that NMR and HPSEC provided strongly correlated perspectives, with 86 % of the discrimination between the organic samples common to both techniques. Conversely, py-GCMS was found to provide a unique, and thus complementary, perspective.

In the present study, catalytic wet oxidation (CWO) was investigated for the destruction of organic pollutants in the thermally pretreated effluent from a pulp and paper mill under moderate temperature and pressure conditions. The thermal pretreatment studies were conducted at atmospheric pressure and 368K using copper sulfate as a catalyst. The thermal pretreatment reduced COD by about 61%. The filtrate of the thermal pretreatment step was used at pH 8.0 for CWO at 383-443K temperature and a total pressure of 0.85MPa for 4h. Catalysts used for the reaction include copper sulfate, 5% CuO/95% activated carbon, 60% CuO/40% MnO(2), and 60% CuO/40% CeO(2). Maximum COD reduction was found to be 89% during CWO step using 5% CuO/95% activated carbon with a catalyst loading of 8gl(-1) at 443K and 0.85MPa total pressure. Overall COD reduction for the pretreatment and the CWO was found to be 96%. Besides this, 60% CuO/40% CeO(2) catalyst also exhibited the similar activity as that of obtained with 5% CuO/95% activated carbon catalyst at 423K temperature and 0.85MPa total pressure. The pH of the solution during the experimental runs decreases initially due to the formation of carboxylic acid and then increases due to the decomposition of acids.

With the increasingly strict supervision of the ecological environment and the continuous improvement of pollution control requirements, there are many options for water pollution control technology in the pulp and paper industry. How to choose reasonable and effective control technology has become the focus of attention. In this paper, a water pollution control technology evaluation model based on the Pythagorean language neutrosophic set (PLNS) is proposed for the first time. Firstly, the concept of PLNS is defined and its characteristics are discussed. Then the score function and accuracy function of the Pythagorean language neutral number (PLNN) are defined. To apply PLNNs to multi-attribute decision-making, PLNN power-weighted geometric operator (PLNNPWG) and PLNNPWG geometric Heronian mean operator (PLNNPWG-GHM) are proposed and a multi-attribute decision-making method is proposed. Finally, this method is used to evaluate the water pollution control technology of the pulp and paper industry. Through the experimental results, it can be seen that if the comprehensive weights are used, elemental chlorine-free (ECF) clean bleaching technology is the best choice, when using single weights to calculate, in technical characteristics, ECF clean bleaching performed best. In economic cost, chlorination, enhanced alkali treatment, hypochlorite (CEH) three-stage bleaching performed best. In operation management and environmental impact, ECF clean bleaching and total chlorine-free (TCF) clean bleaching had almost the same score. This model can provide a reliable basis for enterprises to choose the appropriate water pollution control technology and also provide strong support for the management department to recommend the best feasible technology. [Display omitted] • Propose the Pythagorean language neutrosophic set (PLNS). • Define the score function and accuracy function of Pythagorean language neutral number (PLNN). • Propose the PLNN power-weighted geometric (PLNNPWG) and PLNNPWG geometric Heronian mean (PLNNPWG-GHM) operators. • Propose a decision-making method to evaluate the water pollution control technology of pulp and paper industry. • Provide strong support for the management department to recommend the best feasible technology. [ABSTRACT FROM AUTHOR]

Copyright of China Pulp & Paper is the property of China Pulp & Paper Magazines Publisher and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Water resource pollution is a significant issue that is only becoming worse even with the appropriate laws in place. Because effluent contaminants tend to accumulate in aquatic species, genotoxic researches on these pollutants are crucial. Therefore, using aquatic organisms to measure Genotoxicity is a highly helpful environmental monitoring technique. River Ami is a significant body of water in Maghar Sant Kabir Nagar, Uttar Pradesh, India that was contaminated by many industrial sources' untreated effluents. The current study set out to assess the genotoxic effects of these effluents on Channa punctatus fish as well as their toxic impacts on water quality. The research of Genotoxicity (the impact of bleached effluent on fish micronuclei) was conducted using the micronuclei. Fish treated with bleached effluent showed a significant (p<0.05) increase in the quantity of micronuclei compared to fish that were directly collected from the Aami River. Temperature, pH, DO, BOD, COD, TSS, and TDS are among the physico-chemical characteristics of a body of water that are assessed seasonally. All of these metrics were significantly higher than the Central Pollution Control Board of India's suggested tolerance limit. [ABSTRACT FROM AUTHOR]

A further closure of the water circuit in paper mills with a relative high optimization of their water network is limited by the increase of contamination in the water and runnability problems of the paper machine. Therefore, new strategies for saving water must be focussed on the treatment of final effluents of the paper mill, aiming to obtain high quality water that may replace fresh water use in some applications. An appropriate treatment train performed at pilot scale, consisting on a previous clarification stage followed by anaerobic and aerobic treatments, ultrafiltration, and reverse osmosis, made possible producing the highest water quality from the final effluent of the mill. Anaerobic pre-treatment showed very good performance assisting the aerobic stage on removing organics and sulphates, besides it produced enough biogas for being considered as cost-effective. Permeate recovery depended on the silica content of the paper mill effluent, and it was limited to a 50-60%. The reject of the membranes fully met the legislation requirements imposed to effluents arriving to municipal wastewater treatment plants.

Thanks to multiple recirculation of process water, the German paper industry has succeeded in decreasing the specific fresh water demand from an average of 50 m3/t thirty years ago to 13 m3/t today. Although the increasing closure of white water loops creates many problems, it is bound to be part of the German paper industry's ongoing development. For a few years, in the production of packaging paper, two paper mills have been running with a totally closed water system including different process water treatment plants as 'kidneys'. This paper presents a comprehensive survey of the pros and cons of closed process water systems followed by significant examples of effluent-free production of corrugating medium and test liner. Additionally, operation experiences and economic aspects are discussed.

Since the early 1980s, anaerobic treatment of industrial effluents has found widespread application in the pulp and paper industry. Over 200 installations are treating a large variety of different pulp and paper mill effluents. Amongst various anaerobic systems the UASB and IC are the most applied anaerobic reactor systems. Anaerobic treatment is well feasible for effluents originated from recycle paper mills, mechanical pulping (peroxide bleached), semi-chemical pulping and sulphite and kraft evaporator condensates. The advantages of anaerobic pre-treatment are (1) net production of renewable energy (biogas), (2) minimized bio-solids production, (3) minimal footprint and (4) reduced emission of greenhouse gases. Via in-line application of anaerobic treatment in closed circuits (paper kidney technology) further savings on cost of fresh water intake and effluent discharge levies are generated.

Two streams of wastewater from the Kraft Pulp and Paper Mills at Webuye are released from the pulping, bleaching and paper pressing departments. One stream is made up of clear wastewater and the second is made up of turbid wastewater. The wastewaters from the mills are treated using oxidation ponds, after which the treated wastewater is discharged into the River Nzoia. The wastewater was analysed for Cd, Cr, Cu, Ni, Pb. Zn, Ca, K, Mg and Na. The results are that the concentrations of Ca and Na significantly increased in the treated wastewater. The concentrations of Cd, Pb, Zn, K and Mg also increased in the treated wastewater, though not significantly. The concentrations of Cr, Cu and Ni decreased in the treated wastewater but not significantly. Mass loadings of the metals discharged into River Nzoia were calculated. It was found that the mean mass loading of two metals (Ca and Na) significantly increased in the treated wastewater. Five metals (Cd, Pb, Zn, K and Mg) increased in the treated wastewater although not significantly. Three metals (Cr, Cu and Ni) decreased in the treated wastewater but the decrease was not significant. The concentrations of Cd, Cu, Ni, Pb and Zn were all above the limits set by EC for drinking water. These findings pose serious questions of the effectiveness of oxidation ponds system to safeguard the receptor against pollutants from the pulp and paper industry at Webuye.

The fish community in sublittoral and profundal waters, at stony shores, and densities of vendace larvae were studied in the southern Lake Saimaa, Finland. The objective was to investigate the possible recovery of fish populations after modernizations at the pulp and paper mills discharging into the lake. Sublittoral and profundal waters were studied by gill net trial fishings, stony shores by electrofishing, and vendace larvae by beach seine. The research area was divided in a polluted (0.5-4.0% effluent), an intermediate (0.1-0.5%) and a 'clean' reference area. The fish community in sublittoral and profundal waters in the lake was dominated (> 60%) by perch and roach. Relative abundance of fish was highest in the polluted area, and lowest in the reference area. The number of species caught was similar among areas. The abundance of bleak and ruffe was highest in the polluted area, while the abundance of vendace and whitefish was highest in the intermediate and reference area. The fish fauna of stony shores in the lake was dominated by bullhead, stone loach and minnow, densities were lowest at polluted shores and highest in the intermediate area. Minnow, apparently a more sensitive species to pulp mill effluents, were not caught at the most polluted shores. The catch of vendace larvae was similar among areas, larvae were also caught in the vicinity of the mills. Compared with before the modernization at the mills, the relative abundance of perch in the polluted area was increased, ruffe decreased, while populations of whitefish and vendace showed signs of recovery. These changes may be explained by the reduced nutrient load and toxicicity of pulp mill effluents. At present, the fish community in the polluted area can be considered typical for a moderate eutrophication.

A study was conducted to determine the influence of decontamination on winter flounder living downstream from a pulp and paper mill. The fish and controls were held 8-26 weeks under contaminant-free conditions in aquaria supplied with ambient sea water. Groups of flounder, for comparison, were also sampled near the paper mill at the time of or following autopsy. No differences were apparent in length/organ-weight relationships between depurated and control groups after 26 weeks at 0-6 degrees C, but condition factor, gonadal and hepatosomatic indices, coincident with elevated levels of detoxifying enzymes, differed from field-derived samples. Pathological changes, including hemosiderin deposits in the liver and spleen, decreased, whereas pericholangitis and clear cell foci were apparent in the depurated fish and in the field samples. In two additional groups decontaminated for 8-16 weeks at 6-16 degrees C, there was no evidence of pericholangitis, but hemosiderin deposits persisted and an increase of fibrosis and clear cell foci occurred in contrast to the field group. These results suggest that some tissue repair in the liver transpired primarily during summer while other lesions, such as preneoplastic clear cell foci, which were probably induced prior to depuration, increased, but hemosiderin concentration remained unchanged. The latter observation is consistent with previous studies that suggest that hemosiderin concentration is not seasonally but age influenced.

Papermill sludge (PMS) is generated during the wastewater treatment process of paper production. Its handling and disposal techniques are of great concern for the environment. It can be landfilled as a waste, or it can be recycled and converted into useful products of high value. It has a very promising application as an absorbing agent for the cleaning of water surfaces polluted with hydrophobic substances (vegetable, synthetic and mineral oils, animal fats, fuels, organic chemicals and even coal dust). Here, we present the pretreatment procedure (hydrophobation, mechanical and thermal treatments) of PMS that produces a lightweight absorbent material (HAWSC - high efficiency absorbent for water surface cleaning), which floats on the water surface and binds hydrophobic pollutants with considerably higher efficiency than commercially available mineral and synthetic absorbents. After its application, it can be incinerated, due to its high caloric value, to produce energy. The incineration residues can then be formed into granules that can be used as an efficient absorbent for fluids spilled onto solid surfaces., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

With oil pollution in water posing a serious threat to the ecosystem, it's of great importance to explore superhydrophobic materials that are environment-friendly and easy to obtain for oil–water separation. Herein, we report a novel one-step silanization strategy to fabricate superhydrophobic cellulose paper based on the air-induced vertical polymerization of a long-chain alkyltrichlorosilane. The as-prepared paper exhibited remarkable superhydrophobicity with a water contact angle of ~ 165° and a water sliding angle of ~ 1.9° owing to the formation of micro/nanostructured, honeycomb-like polyorganosiloxane agglomerates anchored on the surface. Moreover, when subjected to strong acid/alkali solutions and mechanical forces (sonication and sandpaper abrasion), the superhydrophobic paper showed excellent durability. Due to the extreme wetting properties, namely superhydrophobicity and superoleophilicity, such paper could be used for selectively separating oil from various oil/water mixtures. The proposed method for fabricating superhydrophobic paper has many advantages in terms of cost, simplicity and scalability, making it very promising for real-world application. [ABSTRACT FROM AUTHOR]

India has a large number of paper manufacturing units, with mills varying in size of operations and type of product, scattered all over the length and breadth of the country. Present study deals with the survey of four different pulp and paper mills (Mill A, Mill B, Mill C and Mill D) in India, differing in their scale of operation as well as raw material usage. Physico-chemical characterization of wastewaters produced by different processing units like digestor house liquors, bleaching section, paper machine backwaters, combined inlet to the ETP and outlet to ETP, for all the four mills, was conducted. Different parameters like pH, Color, COD, BOD, percent Na, SAR, TDS and Total hardness were analyzed and compared. Highly significant differences were thus found between all the processing units of all four mills with p values < 0.01. This evaluation showed that though these mills have effluent treatment facilities installed in their premises, improvements are still needed to increase their efficiencies for treating the discharged wastewaters.

The degradation of Kraft E1 pulp mill effluent was studied by four different ozonization oxidation systems (O3/pH3, O3/pH11, O3/pH11/H2O2, O3/pH11/UV). The investigation was focused on the reduction of total organic carbon (TOC), total phenols, color and acute toxicity (monitoring by inhibition of Escherichia coli respiration). For a reaction time of 90 minutes, the O3/pH11/UV was the most effective process for decoloration (45%). The O3/pH11/H2O2, O3/pH11/UV and O3/pH11 processes showed the best results for total phenols reduction (approximately/= 90%). None of the studied processes showed a significant TOC reduction. The O3/pH11/UV and O3/pH11 processes were effective for the acute toxicity reduction. Different kinetic parameters were also determined in order to quantify the reactivity of the effluent towards the applied oxidation systems.

Paper is one of the most widely used materials, due to its application in books, packaging, and office supplies. However, conventional paper has many disadvantages, such as low tensile strength, poor resistance to water and oil contamination, lack of antigraffiti capability, and easily deformed by moisture. Therefore, we proposed a double-layer protective coating that consists of a polyurethane (PU) bottom layer, to enhance tensile strength, and a top polydimethylsiloxane (PDMS) composite layer to enable antigraffiti and contamination-resistant capabilities. In the study, a double-layer coating was applied to conventional paper, using a simple two-step spraying method. The results showed that the prepared coating structure exhibited outstanding self-cleaning characteristics with respect to both water and oil contamination and adequately demonstrated antigraffiti capability. Moreover, the coating maintained superhydrophobic and oil-stain resistance after four months of outdoor storage. Finally, the tensile strength of the coated paper was 6.3 times as high as that of the original paper, making this coating structure a promising solution to the problems that limit paper from being more widely utilized in commercial and consumer application. [ABSTRACT FROM AUTHOR]