scholarly journals The influence of mechanical, physical and chemical pre-treatment processes of wood surface on the relationships of wood with a waterborne opaque coating

2022 ◽  
Vol 162 ◽  
pp. 106574
Author(s):  
Jure Žigon ◽  
Janez Kovač ◽  
Marko Petrič
Keyword(s):  
Wood Surface ◽  
Treatment Processes ◽  
Pre Treatment ◽  
Physical And Chemical

scholarly journals Influence of the Bottom Color Modification and Material Color Modification Process on the Performance of Modified Poplar

Coatings ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 660
Author(s):  
Qingqing Liu ◽  
Di Gao ◽  
Wei Xu
Keyword(s):  
Chemical Properties ◽  
Target Color ◽  
Modification Process ◽  
Red Color ◽  
The Difference ◽  
Pre Treatment ◽  
Physical And Chemical ◽  
Surface Differentiation ◽  
Color Modification ◽  
And Chemical Properties

According to the old surface coating process of European and American furniture, the surface of modified poplar is first differentiated pre-treatment, and then the bottom color modification and material color modification are respectively applied to the modified poplar after the surface differentiation treatment. The visual physical quantity and physical and chemical properties were measured and compared with mahogany, which is commonly used in old furniture in Europe and America to explore the effect of colorants and coloring steps, as well as different surface pretreatments on the coloring effect. Finally, it is concluded that continuous coloring operations can narrow the difference in brightness and red color value in the coloring layer of modified poplar and mahogany. Continuous coloring operations increase the difference between the yellow-green color values of modified poplar and mahogany. Therefore, the coloring difference between modified poplar and mahogany was affected by the colorant and coloring steps. Through color accumulation, the gap between the two in the target color coloring effect can be reduced, thereby reducing the difference between the coloring effect of modified poplar and mahogany.

Prospects and problems of sludge pre-treatment processes

2001 ◽  
Vol 44 (10) ◽  
pp. 121-128 ◽  
Author(s):  
J.A. Müller
Keyword(s):  
Wastewater Treatment ◽  
Phase Changes ◽  
Ozone Treatment ◽  
Thermal Methods ◽  
Sludge Treatment ◽  
Freeze Thaw ◽  
Positive Effects ◽  
Treatment Processes ◽  
Stage Of Development ◽  
Pre Treatment

Pre-treatment processes have been developed in order to improve subsequent sludge treatment and disposal. Disintegration of sludge solids in the aqueous phase changes the sludge structure and solubilizes organic matter. This paper provides an overview of the applications of wet disintegration in wastewater and sludge treatment. Applied disintegration techniques such as mechanical, thermal, chemical and biological methods are briefly described. The methods are compared regarding energy consumption, operational reliability and stage of development for application on wastewater treatment plants. Mechanical and thermal methods appear to be most suitable at this stage. The effects of pre-treatment on subsequent sludge treatment processes and the wastewater treatment are described. The performance of various methods is assessed. For the improvement of stabilization, mechanical and ozone treatment as well as thermal treatment perform best. Dewatering can be enhanced by thermal and freeze/thaw treatment. All methods show positive effects in the reduction of the number of pathogens. Pre-treatment leads to secondary effects like the generation of recalcitrant compounds and odor, which is mainly a problem of thermal and ozone treatment. The evaluation of capital and operational costs is difficult, because of the lack of full-scale experience. Especially thermal, freeze/thaw and biological treatments can be realized at low costs if the conditions are appropriate. Nevertheless, the economic efficiency has to be investigated critically for each individual application.

Investigation and assessment of sludge pre-treatment processes

2004 ◽  
Vol 49 (10) ◽  
pp. 97-104 ◽  
Author(s):  
J.A. Müller ◽  
A. Winter ◽  
G. Strünkmann
Keyword(s):  
Fine Particles ◽  
Degradation Process ◽  
Solid Content ◽  
Ozone Treatment ◽  
Treatment Processes ◽  
Sludge Properties ◽  
Pre Treatment ◽  
The Cost ◽  
Degree Of Degradation ◽  
Cell Disintegration

The pre-treatment of sludges by disintegration will result in a number of changes in sludge properties. Floc destruction as well as cell disintegration will occur. This leads to an increase of soluble substances and fine particles. Furthermore, biochemical reactions may appear during or immediately after disintegration. The influence of disintegration of excess sludge on anaerobic digestion was studied in full scale. A stirred ball mill, an ultrasound disintegrator, a lysate centrifuge and ozone treatment were used. The results of the degradation process were compared to a reference system without pre-treatment. An enhancement of the degree of degradation of 7.4% to 20% was observed. The pollution of sludge water as well as the dewatering properties of the digested sludge were investigated. COD and ammonia in the sludge water were increased and a higher polymer demand was observed while the solid content after dewatering stayed almost unchanged. Based on these results the cost effectiveness has been assessed taking into account different conditions (size of WWTP, cost for disposal, etc.). Capital and energy costs are the main factors while the decrease in disposal costs due to the reduced amount of sludge is the main profit factor.

scholarly journals The Study of the Physical and Chemical Behavior of Activated Carbon in the Permeable Concrete for Light Traffic Paving

2019 ◽  
Vol 7 (9) ◽  
pp. 175-192
Author(s):  
Ednei Bruce Da Silva ◽  
Antônio Estanislau Sanches ◽  
David Barbosa de Alencar ◽  
Mike Jordan Braz Izel ◽  
Camily Murrieta Vasconcelos Oliveira Bezerra ◽  
...  
Keyword(s):  
Activated Carbon ◽  
Fine Aggregate ◽  
Light Traffic ◽  
Conventional Concrete ◽  
Biological Activated Carbon ◽  
Treatment Processes ◽  
Basic Sanitation ◽  
Slow Filtration ◽  
Physical And Chemical

The water treatment processes in which microorganisms act are margin filtration, slow filtration and biological activated carbon (CAB) [2]. For this research, a study of permeable concrete with the addition of 2% activated carbon for light traffic paving was performed. The objective of this research is to identify the feasibility of using this concrete so that filtered water can reach at least the basic sanitation networks, with a better quality to be treated. For this, characterizations of the quality of the concrete component materials were made with a novelty, using the fine aggregate (sand). After the characterizations, the permeable concrete traces with mechanical strength of 30MPa were made. Dosing analyzes followed with molding, curing and rupture of concrete specimens. The results of the arithmetic mean of the axial compression of conventional concrete at 28 days were 34.2 MPa and the concrete with the addition of activated carbon was 32.2 MPa, reaching the expectations of strength. Complementary experiments were performed for the quality of the water filtered by the CP's, the pH, the alkalinity and the chlorine content were analyzed. The pH of the conventional concrete found was 7.6 and the concrete with the addition of activated carbon was between 7.2 and 6.8, which may be the best result found

Adsorption of MIB by activated carbons produced using several activation techniques

2002 ◽  
Vol 2 (5-6) ◽  
pp. 265-270
Author(s):  
R. McCallum ◽  
F. Roddick ◽  
M. Hobday
Keyword(s):  
Heat Treatment ◽  
Activated Carbon ◽  
Water Treatment ◽  
Organic Compounds ◽  
Activated Carbons ◽  
Alkali Treatment ◽  
Power Station ◽  
Steam Activation ◽  
Pre Treatment ◽  
Physical And Chemical

Water treatment authorities use activated carbon as the best available technology to remove low molecular weight organic compounds from potable water. In Australia, pollutants of concern include secondary metabolites from bacterial and cyanobacterial blooms which are highly odorous and, in some cases, toxic. Of these compounds, 2-methylisoborneol (MIB) is one of the most common and its unpleasant musty earthy odour can be detected at or above approximately 10 ng/L. Difficulties in using activated carbon to target such small organic compounds arise when the water has high concentrations of natural organic matter (NOM), as these compounds also adsorb on activated carbon. The adsorption of NOM on activated carbon increases the cost of using this material in water treatment due to competition with the target organic compounds, reducing the capacity of the activated carbon for the latter. The surface of activated carbon can be tailored during production to provide physical and chemical characteristics that can either aid or hinder the adsorption of particular compounds. One source of activated carbon currently under investigation at RMIT University is brown coal char waste from power stations. This waste, currently disposed of to landfill, is potentially an option for activated carbon production. This material has the advantage that it has already been carbonised at around 500°C in the power generation process. This means that less energy is required to produce activated carbon from power station char compared to coal, making the final product cheaper to produce. Previous work at RMIT has shown that steam activated power station char can remove organic compounds from water. Production of a range of activated carbons from power station char (PSC) was undertaken using different activation methods, including steam activation, steam activation with acid pre-treatment, alkali heat treatment, and Lewis acid heat treatment. The different activation methods produced activated carbons with different pore size distributions, in particular, the acid pre-treatment increased the surface area and porosity significantly compared with steam activation, and the alkali treatment increased the microporosity. Adsorption of MIB on these activated carbons was evaluated to determine the relationship between physical and chemical interactions of the activated carbon and adsorption. Adsorption of MIB on these activated carbons was found to be dependent on the secondary micropore volume. Lewis acid treatment and alkali treatment was not involved in the generation of many of these secondary pores, hence carbons from these treatments did not perform well in adsorption tests. The best adsorption results were achieved with steam activated or acid treated steam activated samples which performed comparably to commercial products. Initial results showed that competition from NOM adsorption was lowest with the PSC activated carbons, allowing greater adsorption of MIB, compared with the commercial activated carbons.

Effects of chemical–physical pre-treatment processes on hemp fibres for reinforcement of composites and for textiles

2006 ◽  
Vol 24 (2) ◽  
pp. 113-118 ◽  
Author(s):  
Anne Belinda Thomsen ◽  
Anders Thygesen ◽  
Vibeke Bohn ◽  
Kristina Vad Nielsen ◽  
Bodil Pallesen ◽  
...  
Keyword(s):  
Treatment Processes ◽  
Hemp Fibres ◽  
Pre Treatment

scholarly journals Pretreatment of Lignocelollusic Biomass Based on Improving Enzymatic Hydrolysis

2017 ◽  
Vol 5 (1) ◽  
pp. 1-11 ◽  
Author(s):  
Meysam Madadi ◽  
Yuanyuan Tu ◽  
Aqleem Abbas
Keyword(s):  
Alternative Energy ◽  
Treatment Method ◽  
Accessible Surface Area ◽  
Effective Parameters ◽  
Sugar Degradation ◽  
Treatment Technologies ◽  
Pre Treatment ◽  
Accessible Surface ◽  
Alternative Energy Resources ◽  
Physical And Chemical

Lignocellulosic materials among the alternative energy resources are the most desirable resources that can be employed to produce cellulosic ethanol, but this materials due to physical and chemical structure arranges strong native recalcitrance and results in low yield of ethanol. Then, a proper pre-treatment method is required to overcome this challenge. Until now, different pre-treatment technologies have been established to enhance lignocellulosic digestibility. This paper widely describes the structure of lignocellulosic biomass and effective parameters in pre-treatment of lignocelluloses, such as cellulose crystallinity, accessible surface area, and protection by lignin and hemicellulose. In addition, an overview about the most important pre-treatment processes include physical, chemical, and biological are provided. Finally, we described about the inhibitors enzymes which produced from sugar degradation during pre-treatment process and the ways to control this inhibitors.Int. J. Appl. Sci. Biotechnol. Vol 5(1): 1-11

The reliability of radiocarbon dates of different carbon fractions in the Australian tropical savannas: A case study from Sanamere Lagoon, northeast Australia

2020 ◽  
Author(s):  
Maria Rivera-Araya ◽  
Michael Bird ◽  
Cassandra Rowe ◽  
Sean Ulm ◽  
Vladimir Levchenko
Keyword(s):  
Chemical Properties ◽  
Treatment Method ◽  
Tropical Lake ◽  
Tropical Lakes ◽  
Radiocarbon Dates ◽  
Carbon Fractions ◽  
Polycyclic Aromatic ◽  
Organic Fractions ◽  
Pre Treatment ◽  
Physical And Chemical

<p>The selection and pre-treatment of a reliable organic fraction from which to acquire radiocarbon dates is fundamental to obtain accurate chronologies. Sampling from tropical lakes is particularly challenging given the adverse preservation conditions and diagenesis in these environments. Our research is the first to examine and quantify the differences between the radiocarbon date results from different carbon fractions and pretreatments from the same depths from a tropical lake sediment core (1.72 m long) located in north Australia to assess which one(s) are more reliable. Six different organic fractions (bulk organics, pollen concentrate, cellulose, stable polycyclic aromatic carbon (SPAC), charcoal >250 um and charcoal >63 um), for a total of 27 radiocarbon dates, were compared in six different depths along the core. Acid-base-acid (ABA), modified ABA (30 % hydrogen peroxide + ABA), 2chlorOx (a novel cellulose pre-treatment method) and hydrogen pyrolysis (hypy) were used to pre-treat the correspondent organic fractions. The oldest date is 31,295 calibrated years before present (cal yr BP) and the youngest is 2,048 cal yr BP, spanning 29,247 years. The smallest offset between the minimum and the maximum age in a given depth was found to be 975 years (between SPAC and charcoal >63 um) and the largest 16,527 years (between pollen concentrate and SPAC). The SPAC fractions pre-treated with hypy consistently yielded older ages compared to all other fraction in most cases, while bulk organics yielded consistently younger ones. The magnitude and consistency of the offsets and the physical and chemical properties of the tested organic fractions suggest that SPAC is the most reliable fraction to date in tropical lake sediments and that hypy successfully removes contamination sourced from exogenous carbon.</p>

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