RESUMO
The current investigation deals with how chemically activated carbon derived from industrial paper sludge (ACPS) performs on sorptive removal of enrofloxacin (ENF), an antibacterial drug from its water solution. Thermogravimetric (TGA) and proximate analysis of raw paper sludge (RPS) were conducted. ACPS was characterized with proximate analysis, XRD, FT-IR, SEM and BET. The influence of five operational parameters viz. adsorbate concentration (initial), dose of adsorbent, pH, temperature, and contact time on the adsorption of ENF onto ACPS has been conducted using batch experiments. The process of adsorption was optimized through ANN (artificial neural network) in addition to RSM (response surface methodology). The maximum percentage removal (95.85%) was achieved at initial ENF concentration 12â¯mg/g, adsorbent dose 1.2â¯g/L, contact duration of 18â¯h and temperature 20⯰C. Kinetic data were best fitted into pseudo-second order kinetic model and adsorption equilibrium study indicates that the adsorption process follows Langmuir isotherm model. Adsorption capacity was noted to have a highest value of 44.44â¯mg/g. A study on thermodynamics of the adsorption process suggests that it exhibits spontaneity, being essentially exothermic. Cost analysis and reusability study confirm that adsorbent produced from industrial paper sludge is cost-effective and reusable. Therefore, ACPS as adsorbent has potency for removing ENF from aqueous solution.
Assuntos
Carvão Vegetal/química , Enrofloxacina/análise , Águas Residuárias/análise , Poluentes Químicos da Água/análise , Adsorção , Antibacterianos/análise , Indústria Editorial , Resíduos Industriais/análise , PapelRESUMO
In traditional publishing, female authors' titles command nearly half (45%) the price of male authors' and are underrepresented in more prestigious genres, and books are published by publishing houses, which determined whose books get published, subject classification, and retail price. In the last decade, the growth of digital technologies and sales platforms have enabled unprecedented numbers of authors to bypass publishers to publish and sell books. The rise of indie publishing (aka self-publishing) reflects the growth of the "gig" economy, where the influence of firms has diminished and workers are exposed more directly to external markets. Encompassing the traditional and the gig economy, the book industry illuminates how the gig economy may disrupt, replicate, or transform the gender discrimination mechanisms and inequality found in the traditional economy. In a natural experiment spanning from 2002 to 2012 and including over two million book titles, we compare discrimination mechanisms and inequality in indie and traditional publishing. We find that indie publishing, though more egalitarian, largely replicates traditional publishing's gender discrimination patterns, showing an unequal distribution of male and female authors by genre (allocative discrimination), devaluation of genres written predominantly by female authors (valuative discrimination), and lower prices within genres for books by female authors (within-job discrimination). However, these discrimination mechanisms are associated with far less price inequality in indie, only 7%, in large part due to the smaller and lower range of prices in indie publishing compared to traditional publishing. We conclude that, with greater freedom, workers in the gig economy may be inclined to greater equality but will largely replicate existing labor market segmentation and the lower valuation of female-typical work and of female workers. Nonetheless, price setting for work may be more similar for workers in the gig economy due to market competition that will compress prices ranges.
Assuntos
Autoria , Indústria Editorial , Sexismo , Indústria Editorial/economia , Preço de Livros , Venda de Livros/economia , Feminino , Humanos , Masculino , Salários e Benefícios/economia , Sexismo/economiaRESUMO
BACKGROUND: Little is known about the epidemiology of contact dermatitis (CD) in print machine operators (PMOs). OBJECTIVE: The aims of this study were to estimate the prevalence of CD and characterize clinically relevant and occupationally related allergens among PMOs undergoing patch testing. METHODS: This was a retrospective cross-sectional analysis of the North American Contact Dermatitis Group data from 1998 to 2014. RESULTS: Of 39,332 patch-tested patients, 132 (0.3%) were PMOs. Among PMOs, most were male (75.0%) and white (92.4%). The majority were printing press operators (85.6%). The most frequent sites of dermatitis were hands (63.6%), arms (29.5%), and face/scalp (24.2%). More than half had an occupationally related skin condition (56.1%). Final diagnoses were most commonly allergic CD (58.3%) and irritant CD (33.3%). Cobalt (20.8%), carba mix (12.5%), thiuram mix (8.3%), and formaldehyde (8.3%) were the most frequent occupationally related allergens. The top allergen sources included inks (22.9%), gloves (20.8%), and coatings/dye/copy/photographic chemicals (14.6%). CONCLUSIONS: Allergic CD, irritant CD, and involvement of exposed body areas were common among PMOs. Common allergens included rubber accelerators, metals, and preservatives.
Assuntos
Alérgenos/efeitos adversos , Indústria Editorial , Dermatite Ocupacional/diagnóstico , Dermatite Ocupacional/epidemiologia , Testes do Emplastro , Adulto , Canadá/epidemiologia , Estudos Transversais , Dermatite Alérgica de Contato/diagnóstico , Dermatite Alérgica de Contato/epidemiologia , Dermatite Irritante/diagnóstico , Dermatite Irritante/epidemiologia , Feminino , Humanos , Tinta , Masculino , América do Norte/epidemiologia , Prevalência , Impressão , Estudos Retrospectivos , Estados Unidos/epidemiologia , Recursos HumanosRESUMO
This article describes a study on the viability of using waste from the paper industry: biomass boiler ash and green liquor dregs to fabricate mortars and concretes. Both types of ash were characterized by obtaining their chemical and mineralogical composition, their organic matter content, granulometry, adsorption and other common tests for construction materials. Seven different mortars were fabricated, one for reference made up of cement, sand, and water, three in which 10, 20, or 30% of the cement was replaced by biomass ash, and three others in which 10, 20, or 30% of the cement was replaced with dregs. Test specimens were fabricated with these mortars to conduct flexural and compression tests. Flexural strength is reduced for all the mortars studied. Compressive strength increases for the mortars fabricated with biomass ash and decreases for the mortar with dregs. Finally, 5 concretes were made, one of them as a reference (neither biomass ash nor dregs added), two of them with replacements of 10 and 20% of biomass ash instead of cement and another two with replacements of 10 and 20% of dregs instead of cement. The compressive and tensile splitting strength increase when a 10% of ash is replaced and decrease in all the other cases. The modulus of elasticity always decreases.
Assuntos
Materiais de Construção , Resíduos Industriais , Papel , Biomassa , Indústria Editorial , Força Compressiva , Dióxido de Silício/química , ÁguaRESUMO
For the paper industry, the disposal and management of the yielded sludge are a considerable challenge. In our work, the paper mill sludge-derived magnetically separable heterogeneous catalyst (PMS-Fe-380) was prepared easily through a facile synthesis method. The morphology and structure of PMS-Fe-380 were fully characterized by means of X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, and Brunauer-Emmet-Teller analysis. The catalytic activity of PMS-Fe-380 was evaluated by degradation of Methylene Blue (MB). The reusability and stability of PMS-Fe-380 were evaluated in five repeated runs, which suggested that PMS-Fe-380 manifested excellent stability of catalytic activity. Moreover, leaching tests indicated that the leached iron is negligible (<0.5mg/L). This study provides an alternative environmentally friendly reuse method for paper mill sludge and a novel catalyst PMS-Fe-380 that can be considered as a promising heterogeneous Fenton-like catalyst.
Assuntos
Corantes/química , Compostos Férricos/química , Resíduos Industriais/análise , Azul de Metileno/química , Esgotos/análise , Indústria Editorial , Catálise , PapelRESUMO
This study investigated the implications of using two grades of limestone from a paper and pulp industry for neutralization of acid mine drainage (AMD) in a pilot sequencing batch reactor (SBR). In this regard, two grades of calcium carbonate were used to neutralize AMD in a SBR with a hydraulic retention time (including settling) of 100 min and a sludge retention time of 360 min, by simultaneously monitoring the Fe(II) removal kinetics and overall assessment of the AMD after treatment. The Fe(II) kinetics removal and overall AMD treatment were observed to be highly dependent on the limestone grade used, with Fe(II) completely removed to levels lower than 50 mg/L in cycle 1 after 30 min using high quality or pure paper and pulp limestone. On the contrary, the other grade limestone, namely waste limestone, could only achieve a similar Fe(II) removal efficiency after four cycles. It was also noticed that suspended solids concentration plays a significant role in Fe(II) removal kinetics. In this regard, using pure limestone from the paper and pulp industry will have advantages compared with waste limestone for AMD neutralization. It has significant process impacts for the SBR configuration as it allows one cycle treatment resulting in a significant reduction of the feed stock, with subsequent generation of less sludge during AMD neutralization. However, the use of waste calcium carbonate from the paper and pulp industry as a feed stock during AMD neutralization can achieve significant cost savings as it is cheaper than the pure limestone and can achieve the same removal efficiency after four cycles.
Assuntos
Reatores Biológicos , Carbonato de Cálcio/química , Ferro/química , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/química , Poluição Química da Água/prevenção & controle , Indústria Editorial , Concentração de Íons de Hidrogênio , Mineração , Projetos PilotoRESUMO
OBJECTIVE: This study was designed to determine the correlation between mental health and multiple chemical sensitivity (MCS). METHOD: The present study was conducted at two companies in 2011; both in Kyushu, Japan. The "subjective symptoms" subscale of the "Self-diagnosis Checklist for Assessment of Workers' Accumulated Fatigue" was used as a mental health subscale. To determine if multiple chemical exposure has an impact on mental health, we composed an original path model using structural equation analysis. RESULT: Our final path model can be regarded as good: CMIN/DF = 1.832, CFI = 0.996, and RMSEA = 0.038, AIC = 71.158. As expected, chemical sensitivity and other chemical sensitivity scores predicted the health effects of multiple chemical exposure (ß = 0.19, 0.64). Mental health was predicted by symptom severity and life impact (ß = 0.56 and 0.12), which were both affected by multiple chemical exposure (ß = 0.38 and 0.89, respectively). CONCLUSION: As far as we are aware, this is the first study using path analysis to explore whether MCS can indicate mental health in worker populations worldwide, and we found a significant causal relationship between them. This could indicate that more focus should be placed on the impact of MCS on mental health in future investigations.
Assuntos
Indústria Manufatureira , Saúde Mental , Sensibilidade Química Múltipla/epidemiologia , Sensibilidade Química Múltipla/psicologia , Exposição Ocupacional , Adulto , Automóveis , Indústria Editorial , Feminino , Humanos , Japão/epidemiologia , Masculino , Saúde Mental/estatística & dados numéricos , Pessoa de Meia-Idade , Sensibilidade Química Múltipla/etiologia , Índice de Gravidade de Doença , Inquéritos e QuestionáriosRESUMO
The biomass content of material from pulp and paper production (a mixture of waste and paper and thin layer packaging plastics) is determined by the adapted balance method. This novel approach is a combination of combustion elemental analysis (CHNSO) and a data reconciliation algorithm based on successive linearisation for evaluation of the analysis results. It also involves less effort and expense than conventional procedures. However, the CHNSO technique only handles small mass amounts (few hundred milligrams), so cryogenic impact milling was applied for particle size reduction below 200 µm in order to generate homogeneous, representative analysis samples. The investigation focuses on the parameters biogenic content as a percentage of the total mass xB and xB (TC), which is the biomass stated as a fraction of the total carbon value. The results are within 1%-5% of the data obtained by the reference methods, namely the selective dissolution method and (14)C- method. Additionally, advantages and drawbacks of the adapted balance method in comparison with standard methods are discussed, showing that the adapted balance method is a method to be considered for the determination of biomass content in solid recovered fuels or similar materials.
Assuntos
Biocombustíveis/análise , Indústria Editorial , Monitoramento Ambiental/métodos , Resíduos Industriais/análise , Algoritmos , Biomassa , PapelRESUMO
A 90 day study was conducted to evaluate the efficiency of an exotic earthworm species (Eudrilus eugeniae) for decomposition of different types of organic substrates (mixed liquor suspended solids, cow dung and leaf litter) into valuable vermicompost. Mixed liquor suspended solids (MLSS) and leaf litter (LL) were mixed with cow dung (CD) in eight different ratios with three replicates for each treatment. All vermibeds expressed a significant decrease in pH, organic carbon, C:N ratio and an increase in total nitrogen, phosphorus and potash. Overall, earthworms could maximize decomposition and mineralization efficiency in bedding with lower proportions of MLSS. Maximum value for earth worm zoo mass and higher concentration of nutrient content was observed in CD + MLSS + LL in 1:1:2 ratios. Earthworm mortality tended to increase with increasing proportion of MLSS and maximum mortality in E. eugeniae was recorded for MLSS treatment alone. Results indicate that vermicomposting might be useful for managing the energy and nutrient of MLSS on a low-input basis. Products of this process can be used for sustainable land restoration practices.
Assuntos
Poluição Ambiental/prevenção & controle , Recuperação e Remediação Ambiental/métodos , Oligoquetos/metabolismo , Poluentes do Solo/metabolismo , Animais , Biodegradação Ambiental , Indústria Editorial , Poluição Ambiental/análise , Índia , Resíduos Industriais/análise , Espécies Introduzidas , Eliminação de Resíduos/métodos , Poluentes do Solo/análiseRESUMO
Based on the physical and chemical properties as well as calorific values of pulp sludge and textile sludge, this study investigates the differences between manufacturability, relationship between extrusion pressure and formability, as well as stability and combustion behaviors of extruded sludge-derived fuel briquettes (ESBB) and cemented sludge-derived fuel blocks (CSBB). The optimum proportion and relevant usage ESBB policies are proposed as well. Experimental results indicate that a large amount of water can be saved during the ESBB manufacturing process. Additionally, energy consumption decreases during the drying process. ESBB also has a more compact structure than that of CSBB, and its mean penetration loading is approximately 18.7 times higher as well. Moreover, the flame temperature of ESBB (624-968°C) is significantly higher than that of CSBB (393-517°C). Also, the dry bulk density and moisture regain of ESBB is significantly related to the penetration loading. Furthermore, the optimum mix proportion of ESBB is co-determined by the formability of pulp sludge and the calorific values of textile sludge. While considering the specific conditions (including formability, stability and calorific values), the recommended mix proportion for ESBB is PS50TS50.
Assuntos
Indústria Editorial , Conservação dos Recursos Naturais , Eliminação de Resíduos/métodos , Esgotos/química , Indústria Têxtil , Conservação de Recursos Energéticos , Dessecação , Temperatura , Água/análiseRESUMO
Discharging untreated highly acidic (pH<4.0), organic and nutrients rich monosodium glutamate wastewater (MW), and highly alkaline (pH>10.0) paper-mill wastewater (PW) causes environmental pollution. When acidity of MW neutralized (pH 6.5±0.1) with PW and lime (treatments represented as MW+PW and MW+Lime), then MW may be utilized as a potential source of nutrients and organic carbon for sustainable food production. Objectives of this study were to compare the effects of PW and lime neutralized MW and chemical fertilizers on maize (Zea mays L. cv. Snow Jean) plant growth, yield, nutrients uptake, soil organic matter and humic substances. The field experiment was carried out on maize using MW at 6000 L ha(-1). Impacts of the MW application on maize crop and soil properties were evaluated at different stages. At harvest, plant height, and plant N and K uptake were higher in MW treatment. Leaf area index at 60 days after sowing, plant dry matter accumulation at harvest, and kernels ear(-1) and 100-kernel weight were higher in MW+Lime treatment. Kernel N, P, K, Mn, Fe and Zn, and plant Zn uptake were highest in MW+Lime. Plant Fe uptake, and soil organic matter and humic substances were highest in MW+PW. The MW+PW and MW+Lime treatments exhibited comparable results with chemically fertilized treatment. The MW acidity neutralized with lime showed positive impacts on growth, yield and nutrients uptake; nevertheless, when MW pH neutralized with PW has an additional benefit on increase in soil organic matter and humic substances.
Assuntos
Indústria Editorial , Fertilizantes/toxicidade , Resíduos Industriais/análise , Glutamato de Sódio/toxicidade , Águas Residuárias/toxicidade , Zea mays/efeitos dos fármacos , Substâncias Húmicas/análise , Solo/química , Zea mays/crescimento & desenvolvimento , Zea mays/metabolismoRESUMO
Removal batch assays of phosphates from a synthetic wastewater (SWW) and a pulp and paper mill wastewater (PPWW) with two forestry biomass ashes were performed. The supernatants were not only chemically characterized but also the ecotoxicity was determined using two organisms: Vibrio fischeri and Artemia franciscana. The addition of fly ash and bottom ash to the SWW in solid/liquid (S/L) ratios of 3.35 and 9.05 g L(-1), respectively, achieved removal percentages of phosphates >97% for both ashes. The addition of fly ash and bottom ash to the PPWW in S/L ratios of 34.45 and 46.59 g L(-1), respectively, yield removal percentages of phosphates >90% for both ashes. According to the results of the Langmuir and Freundlich isotherms, the removal of phosphates from the SWW was mainly explained by surface removal mechanisms, while the removal from the PPWW was partially explained by multi-layer mechanisms. The supernatants resulting from the treatment of SWW and PPWW with both biomass ashes did not present acute ecotoxicity.
Assuntos
Cinza de Carvão/toxicidade , Fosfatos/metabolismo , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/química , Poluentes Químicos da Água/metabolismo , Aliivibrio fischeri/efeitos dos fármacos , Animais , Artemia/efeitos dos fármacos , Indústria Editorial , Cinza de Carvão/metabolismo , Agricultura Florestal , Papel , Fosfatos/química , Águas Residuárias/análise , Poluentes Químicos da Água/químicaRESUMO
The conventional biological treatment methods employed in the pulp and paper industries are not effective in reducing the colour and chemical oxygen demand (COD). The white-rot fungi are reported to have the ability to biodegrade the lignin and its derivatives. This paper is focused on the biological treatment of pulp mill effluent from a bagasse-based pulp and paper industry using fungal treatment. Experiments were conducted using the white rot fungus, Trametes versicolor in shake flasks operated in batch mode with different carbon sources. The decolourisation efficiencies of 82.5% and 80.3% were obtained in the presence of 15 g/L and 5 g/L of glucose and sucrose concentrations respectively with a considerable COD reduction. The possibility of reusing the grown fungus was examined for repeated treatment studies.