Search results for "pulp and paper"
showing 10 items of 410 documents
Aspen Plus process-simulation model: Producing biogas from VOC emissions in an anaerobic bioscrubber
2018
A process-simulation model for a novel process consisted of an anaerobic bioscrubber was developed in Aspen Plus®. A novel approach was performed to implement the anaerobic reactor in the simulation, enabling it to be connected to the scrubber. The model was calibrated and validated using data from an industrial prototype that converted air emissions polluted with volatile organic compounds with an average daily concentration of 1129 mgC Nm−3 into bioenergy for more than one year. The scrubber, which showed a removal efficiency within 83-93%, was successfully predicted with an average absolute relative error of 5.2 ± 0.08% using an average height-to-theoretical-plate value of 1.05 ± 0.08 m …
Effect of Temperature on N2O and NO Emission in a Partial Nitrification SBR Treating Reject Wastewater
2017
Temperature is a very important parameter during nitritation, having a direct effect on ammonia oxidation rate (AOR) and enzymatic activities which relate to both N2O and NO emission. This study aims at investigating the effect of temperature on AOR, N2O and NO production in an enriched ammonia oxidizing bacteria (AOB) sequencing batch reactor (SBR) performing partial nitrification (PN) of synthetic reject wastewater. To achieve that, a SBR was subject to several shifts in temperature (in the range of 30 to 15 °C, 5 °C for each decrease). Cycle studies, which contain two aeration phases, were conducted under each temperature. The results showed that AOR specific exponentially correlates wit…
Valorization of Wastewater from Table Olives: NMR Identification of Antioxidant Phenolic Fraction and Microwave Single-Phase Reaction of Sugary Fract…
2021
The table olive industry is producing a huge amount of wastewater, which is a post-processing cost and an environmental concern. The present study aims to valorize this processing by-product to obtain a value-added product, thereby enhancing resource efficiency and contributing to achieving sustainable development goals (SDGs). In this sense, a chemical reaction-based platform was developed to obtain valuable components, such as levulinic acid (LA) and 5-hydromethylfurfural (HMF). The products were then analyzed using NMR identification of the antioxidant phenolic fraction and microwave single-phase reaction of the sugary fraction. According to the results, the highest concentration of phen…
Photocatalytic ozonation for a sustainable aquaculture: A long-term test in a seawater aquarium
2019
Abstract A long-term test at a laboratory scale with a closed system (a coral reef aquarium) has been carried out to study the potentialities of photocatalytic ozonation and photocatalysis for the removal of noxious organic compounds in recirculating systems (aquaria and recirculating aquaculture systems) working with a minimum make up of new water. Attention has been focused not only on the depuration capabilities but also on possible negative phenomena, some of which could become apparent only at long times. After having tuned the system by setting appropriate operating conditions and procedures, positive results were obtained. In particular, it was observed that the alternation of photoc…
The possibilities of using the aspen poplar seeds (Populus tremula L.) for the purpose of removing monoaromatic hydrocarbons from an aqueous solution
2018
Sorption of oil-related products (including mainly the propellants) is the very basic process that counteracts spreading these types of pollution into environment. Plenty of synthetic substances are used as sorbents for binding organic compounds (including the monoaromatic hydrocarbons) both from the surface and underground waters. The aim of this paper is to present results of the research on the possibilities of using the aspen poplar (Populus tremula L.) seeds as a sorbent of monoaromatic hydrocarbons from an aqueous solution. In order to increase sorption capacity, the seeds biomass was submitted for the process of mercerizing in diversified time and temperature in water and the NaOH so…
Biosorption lead(II) and nikel(II) from an aqueous solution by bacterial biomass
2010
Biosorption lead(II) and nikel(II) from an aqueous solution by bacterial biomass The optimum conditions for biosorption of Pb(II) and Ni(II) from aqueous solution were investigated, by using living and nonliving Pseudomonas fluorescens and Bacillus pumilus isolated from wastewater treatment plant. It was found that the optimum pH for Pb(II) removal by living and nonliving cells was 6.0, while 7.0 for Ni(II) removal. At the optimal conditions, metal ion biosorption was increased as the initial metal concentration increased. The binding capacity by living cells is significantly higher than that of nonliving cells at tested conditions. The maximum biosorption capacities for lead and nickel by …
Description of kraft cooking and oxygen–alkali delignification of bamboo by pulp and dissolving material analysis
2008
Abstract The oxygen delignification of two bamboo ( Bambusa procera ) kraft pulps with kappa numbers of 13.6 and 20.0 were studied under typical conditions. Based on detailed analysis data on both the kraft and oxygen-delignified pulps and the corresponding spent liquors (black liquors and oxygen stage effluents), three yield and four selectivity estimation methods, utilizing component material balances, were tested resulting in the value ranges 96.2–97.9% and 43.5–60.4%, respectively, for oxygen delignification process studied. The traditional selectivity using the viscosity and kappa number relation was 66.9–68.4%. The studied bamboo kraft pulps behaved typically as birch kraft pulps duri…
The Quest for Raw Materials in the British Paper Trade : The Development of the Bamboo Pulp and Paper Industry in British India up to 1939
2018
The British paper trade history was defined since the mid-1850s by a quest for a new raw material to replace rags. The requirements of the paper trade were first met by a discovery that esparto grass from Spain, and later from North Africa, could be utilised in British mills. Beginning in the late 1870s, the success of using esparto encouraged mill developments in British India. The increased dependence on imported wood pulp, the likelihood of a pulp famine, and the consequent increase in price for imported wood pulp drew attention to the possibility of making commercial volumes of good quality pulp from indigenous Indian grasses. Bamboo began being treated after the First World War, when t…
Delignification of bamboo (Bambusa procera acher)
2004
Abstract Delignification of bamboo ( Bambusa procera acher ) was carried out by conventional kraft and soda pulping under varying conditions to determine the relationships between selected cooking parameters (EA 14–20%, sulfidity 0–45%, maximum temperature 165 and 170 °C, and time at maximum temperature 30–95 min) and pulp properties (kappa number, viscosity, and yield). Results indicated that in order to obtain relatively low kappa numbers (17–24), high sulfidity (35–45%) at lower EA (14–16%) increased both pulp viscosity and yield compared to the case of low sulfidity (0–15%) at higher EA (16–18%). Pulp with lower kappa numbers (11–15) and acceptable viscosities (1080–1190 ml/g) can be ob…
Assessment of bio-combustibles production via slow pyrolysis of wine industry residues
2018
With the aim of evaluating the potential production of high energy solid and liquid bio-fuels, a laboratory scale fixed bed reactor (FBR) derived from the standard Gray-King (GK) assay test on coal was used to carry out fixed bed pyrolysis experiments on wine industry by-products. The present study provides results on the pyrolysis of grape marc, residual from wine-making process, consisting of 50% by weight of grape seeds and 50% by weight of grape skins, at temperature between 150 and 500 °C, holding time of 30 minutes. Pyrolysis mass yields of solid (char) and liquid (tar) products and their corresponding energy properties, as a function of reaction temperature, are reported and discusse…