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Paper reviews the method of deodorization and dehydration of sludge-lignin, which is based on the interaction of sludge-lignin with quicklime. CaO added to the sludge-lignin neutralizes lignin in the amount of around 15–20% and within 8–12 days binds volatile sulfur-containing components, functional organic groups and water. The proposed method can effectively reduce unpleasant odor to the level of 2–3 points based on a 5-point scale, as well as to diminish the humidity of the end product by 45–50%, making it look as a free-flowing powder, convenient for transportation and further use. Sludge lignin neutralized by the quicklime can be used for land recycling of municipal solid waste, as well as for other purposes. The recycling technology is characterized by the simple instrumental and the use of the inexpensive chemical reagent. The high economic efficiency of this method makes it promising for solving environmental problems of the ‘Baikal Pulp and Paper Mill’.

International audience; The Covid-19 coronavirus, SARS-CoV-2, is inactivated much faster on paper (3 h) than on plastic (7 d). By classifying materials according to virus stability on their surface, the following list is obtained (from long to short stability): polypropylene (mask), plastic, glass, stainless steel, pig skin, cardboard, banknote, cotton, wood, paper, tissue, copper. These observations and other studies suggest that SARS-CoV-2 may be inactivated by dryness on water absorbent porous materials but sheltered by long-persisting micro-droplets of water on waterproof surfaces. If such physical phenomenons were confirmed by direct evidence, the persistence of the virus on any surface could be predicted, and new porous objects could be designed to eliminate the virus faster.

This study aims to investigate the sewage sludge (SS) drying process by incorporating a by-product formed in the pulp and paper industry (green liquor dregs - GLD) as drying adjuvant. Through an innovative approach, the drying kinetics was modelled, and the final dried product was tested for soil applications. After the characterization phase, small cylinders of SS without and with 0.15 g GLD g SS−1wb (SS_GLD) were dried in isothermal conditions at 70, 100, and 130 °C. The experimental data were fitted by Fick's second law and thin-layer models, and good results were achieved in both cases (R2 > 0.98 and RMSE

Thermochemical heat storage materials for space heating applications such as, ZnSO4 offer high energy storage density, low cost and clean mean of long-term solar energy storage. Herein, we studied the ZnSO4 hydrated salt as potential heat storage material at low temperature and furthermore observed the impact of temperature and concentration on the dehydration/hydration process and enthalpy. The thermal behavior of ZnSO4•7H2O was investigated by applying various dehydration temperatures. The results showed that 85% of water loosed at 100 °C temperature, which released 699 J/g (1.37 GJ/m3) in the dehydration process. The hydration process of ZnSO4.7H2O at 100 °C recovered 541 J/g enthalpies, which delivered 1.1 GJ/m3. Similarly, the dehydration result obtained at 150 °C was the same as showed at 100 °C. However, the enthalpy of hydration was 20% less than prior. The XRD result showed that at higher temperatures agglomeration appeared followed by Van der Waals forces which affect the hydration rate. The result of good cyclability and larger water sorption performance of ZnSO4 make them a promising and suitable for heat storage in space heating application, which can be used as thermochemical heat storage material for thermal storage devices.

Mixed sludge from a pulp and paper mill was hydrothermally carbonized at 180–260 °C for 0.5–5 h with the use of HCl or NaOH for determining the effect of acid and base additions during sludge carbonization. Based on the results carbonization was mainly governed by dehydration, depolymerization and decarboxylation of sludge components. Additive type had a statistically significant effect on hydrochar carbon content and carbon and energy yield, of which especially energy yield increased through the use of HCl. The theoretical energy efficiencies of carbonization increased with decreasing reaction temperature, retention time and the use of HCl and suggested that the energy requirement could be covered by the energy content of attained hydrochar. The BOD5/COD-ratios of analyzed liquid samples indicated that the dissolved organic components could be treated by conventional biological methods.

We developed and characterized a paper-based microfluidic sensor for the on-site diagnosis of drought stress in plants. Proline was used as a biomarker for analyzing drought stress, which was extracted by a colorimetric method using the proline-ninhydrin reaction. Paper was used as the main sensor material for the on-site detection of proline as it is easily transportable and cost-effective. The paper-based sensor was fabricated using wax-printing and origami methods, and the sensor was precoated with ninhydrin to allow for easy and convenient on-site use. Furthermore, a sample-to-ninhydrin ratio of 1:2 was found to confer optimal sensitivity to the drought diagnosis sensor. The concentration of proline in a sample was quantified by red-green-blue analysis to determine the change in green color intensity levels in response to distinct proline concentrations, which were detected by the sensor. The limit of detection of proline using the devised sensor was 657 µM, and the green color intensity level decreased with increasing proline concentration. In addition, the sensor was validated in an experimental drought stress model with Arabidopsis and subjected to drought stress for 21 days, and the amount of proline detected was 10 mM. The devised paper-based microfluidic sensor highlights the possibility of the on-site evaluation of drought stress in plants with potential to be utilized in various agricultural areas in the future.

An estimation of the possibility of dehydration of sludge-lignin of the Baikal Pulp and Paper Mill by the freeze-thaw method was carried out. Change of sludge-lignin structure, physicochemical properties and chemical composition after freeze-thaw are shown. Toxicity and chemical composition of the water solution separated from the sludge-lignin during its freeze-thaw is estimated. An increase in the rate of germination of seeds of the cress in the soil with the addition of the frozen-out sludge-lignin in the ratio "sludge-lignin-soil" 1:3-1:4 is shown. Possibility of application and recommendations for the use of freezed out sludge-lignin as an organic fertilizer is considered. Principal possibility of the worm transformation of sludge-lignin, previously dehydrated by the freeze-thaw method, by red Californian worms Eisenia foetida Andrei Bouche (1972) is shown. The issue of prospects for processing this waste in a fertile bio-soil is discussed. The latter can later be used for recultivation of the territory of the sludge accumulator plots of the Baikal Pulp and Paper Mill.

We investigated the behaviour of salt solutions during the drying process in porous stone and the extraction of salts by paper pulp poultices (PPP). The investigations were carried out at a 300 year old boundary wall of the Worcester College in Oxford, UK, as well as under laboratory conditions. The laboratory blocks of porous, bioclastic limestone (Aflenzer stone, Austria) were cut into stone cubes and prisms (5 × 5 × 5 and 5 × 5 × 20 cm) and soaked first with ultrapure H2O and second with different concentrations (0.1, 0.5 and 1 mol l−1) of a saline solution of NaCl and Na2SO4 to determine their behaviour during the dehydration process under different conditions. After determining the capillary absorption coefficient and the capillary rise behaviour of the stone cubes, we sampled material by PPP and by drilling. The samples were immersed in ultrapure water and the salt ion content was measured via conductivity and ion chromatography (IC). The main aim of the laboratory analysis was to investigate the effectivity of the PPP in extracting salts from the stone and to derive a semi-quantitative calibration (PPP results vs. original salt content). The field work at the college boundary wall comprised sampling (PPP and stone surface material) at surfaces of different weathering features. Finally, the field work results were compared to the laboratory work. The lab experiment results show that approximately 24% of the salts within a 100% saturated stone cube moved into the poultice within the 1 h of application. At 75% and lower saturation degrees, only 14–11% of the salts moved into the respective poultices. For the field setting, the amount of anions extracted by PPP is 6–63% (mean 20.7%) of the amount found in the stone samples. The spatial distribution of salt ion concentrations, collected by poultices, corresponds with the ‘hot spots’ of weathering.

Pulp and inorganic materials were recovered from paper sludge (PS) using 1-butyl-3-methylimidazolium chloride ([BMIM]Cl) and centrifugation. Two types of PS with particle sizes 12 μm and 1 mm were used. Each type was mixed with [BMIM]Cl (PS:[BMIM]Cl = 1:20, w/w) in a polytetrafluoroethylene beaker at 100 °C. The inorganic materials were obtained by centrifugal separation of the [BMIM]Cl solution of pulp components and the solid phase, and the pulp dissolved in [BMIM]Cl was regenerated by addition of ethanol. The amount of pulp components recovered from PS with the smaller particle size was almost 100%, and was greater than from PS with the larger particle size. The recovery rate of inorganic materials from PS with small particle size was lower than that from PS with large particle size. [BMIM]Cl recovered by vacuum distillation and dehydration could be re-used for dissolution of pulp components of PS.

In this study, ionic liquid treatment for increasing the wet strength of cellulose paper was studied. The effects of treatment conditions with the ionic liquid 1-butyl-3-methylimidazolium chloride ([BMIM]Cl) on the wet strength were investigated. First, the [BMIM]Cl (20 g) was melted at 80–100 °C and the paper was immersed in it for 5–60 s. Next, the paper was immersed in ethanol, and finally, it was washed with distilled water. The paper was dried in a hot press at 110 °C and 1.1 MPa for 5 min. The [BMIM]Cl treatment improved the wet strength of the paper. Disintegration of the papers was investigated by immersing them in distilled water, and the paper treated with [BMIM]Cl did not disintegrate. The minimum treatment time required for improvement of the wet strength of the paper was only 5 s. Excess [BMIM]Cl from the original treatment was recovered by vacuum distillation and dehydration was used to treat new paper. This recovered [BMIM]Cl enhanced the wet strength to a level similar to that obtained with the virgin [BMIM]Cl. Therefore, the [BMIM]Cl can be efficiently re-used in this method. The paper treated with [BMIM]Cl will be composed completely of cellulose. Therefore, this method is a viable alternative to treatment by adding chemical such as a polyamideamine epichlorohydrin (PAE).

The effects of moisture, oxygen, and acidity upon the aging of Kraft and thermally upgraded ("Insuldur/spl reg/") papers have been studied in detail. The results for Kraft are consistent with the kinetic model and parameters proposed earlier by Emsley et al., and with the principle that moisture promotes acid-hydrolysis by causing carboxylic acids to dissociate. Moisture is released during the aging of Kraft and, hence, its aging is auto-acceleratory. In contrast, Insuldur consumed moisture under the same conditions, aged more slowly, and its aging was less accelerated by added moisture. 2-Furfuraldehyde (2FAL), which is a dehydration product of pentosans and, hence, an index of moisture production, is also released from Kraft during aging, but not from Insuldur. Acids are, however, produced from both types of paper. Theoretical explanations for these findings are proposed, and their practical implications for transformer maintenance are discussed.

This study aims to produce levulinic acid (LA) from paper towel waste in environment-friendly and economically feasible conditions, and evaluate the difference using solid and aqueous Bronsted acids. Direct dehydration of glucose to LA required sufficiently strong Bronsted acidity, where Amberlyst 36 demonstrated rapid production of approximately 30Cmol% of LA in 20min. However, the maximum yield of LA was limited by mass transfer. In contrast, the yield of LA gradually increased to over 40Cmol% in 1M H2SO4 at 150°C in 60min. The SEM images revealed the conversion in dilute acids under microwave at 150°C resulting in swelling structures of cellulose, which were similar to the pre-treatment process with concentrated acids. Further increase in reaction temperature to 200°C significantly shortened the reaction time from 60 to 2.5min, which saved the energy cost as revealed in preliminary cost analysis.

Rationale The loquat (Eriobotrya japonica Lindl.) is a fruit tree that has been used in Chinese medicine for thousands of years for the treatment of various diseases. The loquat leaf extracts contain several bioactive compounds with antioxidant and antimicrobial properties, and identification of these substances using quick and simple methods has been an analytical trend. Methods The influence of dehydration of loquat leaves (without drying, at 40°C, and at 60°C), the type of solvent (ethanol and methanol), and the method of extraction (shaking and ultrasound) on obtaining extracts containing phenolic compounds and substances with antioxidant and antimicrobial properties was evaluated. The chemical constituents of an extract were identified using paper spray mass spectrometry (PS-MS). Results The extract obtained from the dehydrated leaves at 40°C presented the best results. The extracts obtained from these leaves and with ethanol had the highest values of total phenolics and antioxidant activities, but the methanolic extract subjected to ultrasound had the highest levels of chlorogenic, caffeic, and ellagic acids. All extracts evaluated inhibited the growth of Staphylococcus aureus. Using the PS-MS technique, it was possible to identify the presence of 49 substances such as organic acids, phenolic acids, flavonoids, sugars, quinones, and terpenes. Conclusions In general, extracts of dehydrated leaves at 40°C and extracted with ethanol using ultrasound can be considered a good source of bioactive compounds with potential applications as functional ingredients or additives in the food and pharmaceutical industries. PS-MS was demonstrated to be a simple and ultrafast technique to obtain the chemical profile of the loquat leaf extract.

Проаналізовано конструкції башмачних пресів. Запропоновано принципово нову конструкцію. Розроблено математичну модель пресування паперового полотна на башмачному пресі з новими умовам однозначності, що дає можливість розрахувати кількість видаленої вологи та сухість полотна після пресування., Now forging parts papermaking machines uses many different designs presses. Regardless of the type of construction, the water is filtered through paper to canvas cloth in the transverse direction, filtering water from the cloth can occur in the longitudinal direction (simple presses) or in the transverse direction (shaft with blind holes, grooved shaft, suction shaft).Presses of the native papermaking machines provide a dry cloth when pressed, about 35…40 %. That is not enough, as for drying the paper spent a huge amount of thermal energy in the form of steam, so the development of the press, providing a significant increase in dry is relevant. One way of increasing dryness is usage of shoe press, which by increasing the length of the contact area increased while pressing, so dry cloth before drying section increasing to 50…55 %.Work of presses of papermaking machine is measured by the amount of water removed, and uniform moisture content across the width of fabric after the presses. Dehydration capacity of presses depends primarily on the length of the extrusion zone delighted shaft and on the number of these zones. When pressing simultaneously with dehydration of the paper web changing its structure, increases the contact area between the fibers and the coupling strength between them.In the existing literature does not sufficiently covered shoe-type presses calculation that does not allow constructing them because kinetic regularities of the process is unknown.The purpose of this article is to establish the kinetics of the compaction and main parameters shoe-type press needed to develop methods of calculation and design shoe presses. In the conventional two-shaft presses created considerable common pressure gradient and significantly lower hydraulic pressure gradient. In the developed design will increase the hydraulic pressure gradient by summing the camera of the shoe-type heated compressed air. Under the influence of the total pressure break down the cell structure of the paper web from which water is removed that the action of hydraulic pressure filtered in cloth, from cloth in the grooves of the shaft.This article consists of 5 items: problem, purpose of, the physical model of the process, the mathematical model of the process and conclusions. Each item clearly defines the essence of the article.

Проаналізовано конструкції башмачних пресів. Запропоновано принципово нову конструкцію. Розроблено математичну модель пресування паперового полотна на башмачному пресі з новими умовам однозначності, що дає можливість розрахувати кількість видаленої вологи та сухість полотна після пресування. Now forging parts papermaking machines uses many different designs presses. Regardless of the type of construction, the water is filtered through paper to canvas cloth in the transverse direction, filtering water from the cloth can occur in the longitudinal direction (simple presses) or in the transverse direction (shaft with blind holes, grooved shaft, suction shaft). Presses of the native papermaking machines provide a dry cloth when pressed, about 35…40 %. That is not enough, as for drying the paper spent a huge amount of thermal energy in the form of steam, so the development of the press, providing a significant increase in dry is relevant. One way of increasing dryness is usage of shoe press, which by increasing the length of the contact area increased while pressing, so dry cloth before drying section increasing to 50…55 %. Work of presses of papermaking machine is measured by the amount of water removed, and uniform moisture content across the width of fabric after the presses. Dehydration capacity of presses depends primarily on the length of the extrusion zone delighted shaft and on the number of these zones. When pressing simultaneously with dehydration of the paper web changing its structure, increases the contact area between the fibers and the coupling strength between them. In the existing literature does not sufficiently covered shoe-type presses calculation that does not allow constructing them because kinetic regularities of the process is unknown. The purpose of this article is to establish the kinetics of the compaction and main parameters shoe-type press needed to develop methods of calculation and design shoe presses. In the conventional two-shaft presses created considerable common pressure gradient and significantly lower hydraulic pressure gradient. In the developed design will increase the hydraulic pressure gradient by summing the camera of the shoe-type heated compressed air. Under the influence of the total pressure break down the cell structure of the paper web from which water is removed that the action of hydraulic pressure filtered in cloth, from cloth in the grooves of the shaft. This article consists of 5 items: problem, purpose of, the physical model of the process, the mathematical model of the process and conclusions. Each item clearly defines the essence of the article.

A direct synthesis of methyl levulinate from the degradation of paper sludge in a methanol medium at moderate temperatures (≤ 230 °C) was performed using low-concentration sulfuric acid (≤ 0.05 mol/L) as the catalyst. Response surface methodology with a four-factor, five-level central composite rotatable design was employed to optimize the process conditions for maximized methyl levulinate production under the condition of controlling the dehydration of methanol to dimethyl ether. The yields of methyl levulinate and dimethyl ether as a function of the process variables were fitted to second-order polynomial models through application of multiple regression analyses. A good agreement between the experimental and modeled data was obtained. When the controlled yield of dimethyl ether was less than 20%, a maximum methyl levulinate yield of 54.8% was achieved, corresponding to 27.7% (w/w) overall yield for dry paper sludge. The findings indicated that paper sludge can act as a potential biomass material for upgrading and converting into high value-added chemicals.

Previously, we constructed a cDNA library from Arabidopsis plants that were exposed to dehydration stress for 1 h and obtained the ERD6 clone. Here we report that the ERD6 cDNA consists of 1741 bp and encodes a polypeptide of 496 amino acids having a predicted molecular weight of 54,354. The putative polypeptide of ERD6 is related to those of sugar transporters of bacteria, yeasts, plants and mammals. Hydropathy analysis revealed that ERD6 protein has 12 putative transmembrane domains and a central hydrophilic region. Sequences that are conserved at the ends of the 6th and 12th membrane-spanning domains of sugar transporters are also present in ERD6. These data suggest that ERD6 encodes a sugar transporter. Genomic Southern blots indicate that the ERD6 gene is a member of a multigene family in the Arabidopsis genome. The expression of the ERD6 gene was induced not only by dehydration but also by cold treatment.

Moringa oleifera Lam. is an incredible plant because of vital nutrients such as minerals, vitamins and phytochemicals. The present work is focused on studying the optimization and quality attributes retention in moringa flowers in a freeze dryer (FD). Because the conventional drying process takes more time and energy which will affect the product quality and safety. Response surface methodology (RSM) was employed to optimize the effect of drying temperature (- 65 to - 45°C), vacuum pressure (0.5 to 2.5 mmHg) and drying time (18 to 24 h.) on the vitamin C, total antioxidant activity(TAA) and hygroscopicity (HS) of moringa flower. The developed model response R2 values of vitamin C 0.96, total antioxidant activity 0.97 and hygroscopicity0.95. Based on response surface and desirability (0.74) functions, moringa flower was freeze sdried at - 63.75°C for18 hr under 0.55 vacuum pressure had an optimum level of vitamin C 285.84 mg/100g, TAA 453.20 mg/100g and HS 1.57 percent. Freeze dried moringa flower powder at -55°C had maximum drying characteristics with special reference to high powder recovery (98.75%) and excellent flowability.The first principal component, accounting for 52.15 per cent and two 23.02 per cent of the total variance resolved the different drying temperatures.

The aim of the study is to reduce the negative impact of sewage sludge from the production of cardboard and paper products on the soil by dewatering them with a dehydrator and preparing them for further disposal. Large-scale wastewater sludge from industrial enterprises during utilization is placed at disposal landfills which inevitably leads to a negative impact on the soil cover, littering of territories and withdrawal of the land fund from the economic turnover. In the course of the performed study, the well-known methods of dehydration of moisture-containing material were investigated and there was considered a technical solution to reduce the volume of formation of this type of waste using the example of cardboard and paper production. An electroosmotic installation is proposed, comprising an electrical insulation housing with electrodes: an anode made in the form of a current conductive cover and a cathode made in the form of a conductive perforated bottom of the housing which have a space between them for dehydrated waste. To study the process of sludge dewatering, a series of experiments was carried out on the dehydrator unit with variable voltage parameters between the electrodes. The results of the experimental study were the basis for statistical expressions of the mutual voltage influence between the electrodes, the duration of waste processing, the amount of removed moisture. A model has been obtained that describes the amount of moisture removed during waste treatment. The most productive operating mode of the installation, the time for treatment of waste portion have been established. It has been proven that with the help of an electroosmotic device, up to 70% of moisture is effectively removed from the volume of waste sludge. This makes it possible to significantly decrease their volumes, reduce areas for possible or temporary placement and reduce the ecological load on the environment.

Neglect of vulnerable adults living in long-term care (LTC) homes has been well documented. It often presents first in the physical symptoms of decubitus ulcers, dehydration and urinary tract infections (UTIs). A retrospective cohort study was conducted to examine the relationship between neglect and 90-day mortality among LTC residents in Ontario. An index of neglect was created. Of 106,765 residents, more than one-quarter were found to have at least one indicator of neglect: 13.1% had decubitus ulcers, 13.5% had dehydration, 6.2% had a UTI. Residents who exhibited clinical signs of neglect had higher risks of death within 90 days, both before and during the COVID-19 pandemic.

The paper presents the results of experimental studies of the drying processes of forest biomass, which is promising for energy purposes, - branches of various types of wood: birch, linden, poplar. The experiments were carried out on an installation that provides a low level of error (no more than 8.5%) for measuring the main significant parameters and characteristics of the dehumidification process. According to the results of the experiments, the integral characteristics of the greatest interest (times of complete dehydration) of the drying process have been established. Based on the results of the experiments, a non-monotonic change in the rates of moisture removal was established (the values of W eva increase and decrease with time) at a low-temperature heating mode (at Tg 373 K). At the same time, under conditions of relatively high ambient temperatures (Tg ≥ 373 K), such a change in W eva does not occur. The authors formulated a hypothesis explaining the physical mechanism of such a dependence of the mass rate of moisture removal ( W eva ) on time. An energy analysis of the drying efficiency of three types of biomass has been carried out. It has been shown that branches of birch, poplar and linden are most efficiently dried in conditions of relatively low temperatures (333 ≤ Tg ≤ 353 K). At the same time, it was found that for birch and poplar branches, an increase in the ambient temperature leads to a decrease in the efficiency of the drying process of woody biomass.