• Applied Chemistry for Engineering
• /
• v.28 no.1
• /
• pp.29-34
• /
• 2017

This study provides the identification of corrosion cause substances in super heater tube from a commercial scale circulating fluidized bed boiler. Electricity is produced by the combustion of biomass mainly wood waste. The biomass, super heater tube, super heater tube ash, and boiler ash were collected and components associated with corrosion were analyzed. A large amount of oxygen-containing material was found due to oxidation. The chlorine content was analyzed as 6.1% and 4.3% in super heater tube ash and boiler ash respectively which were approximately 20 and 14 times higher than those of designed values. Also, alkaline metal contents (K, Na, Ca) were very high in ash samples collected from super heater tube and boiler. The tendency of slagging and fouling was predicted based on X-Ray Fluorescence (XRF) results. Basicity that can lead to slagging was estimated as 3.62 and 2.72 in super heater tube and boiler ash, respectively. Slagging would occur with ash content when considering the designed value as 0.35.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
• /
• v.20 no.8
• /
• pp.526-533
• /
• 2008

In this study, theoretical super screen vibration analysis has been carried out to predict the dynamic characteristics of interactive waste particles. In order to approach these problems, it is necessary to have a fundamental understanding the screening process and the process of both the remaining and the passed material on a screen with several interacting screen planes based on Soldinger(1999) was discussed. Here, the vibrating screen is composed of three assemblies such as screen, wastes guide, and supported screen as shown in Fig. 1. This model is regarded vibrator as the system of screen fixed tilt plates. Then materials(or particles) of different size is to be separated by using the eccentric vibrator and classifying tilt plates. As well moisturized construction wastes is more efficient to separate than moisture-less it. In processing separate mechanism, the more materials is light, the more staying time is long. Thus much lighter construction wastes(wood, Styrofoam, etc) and heavier materials are separated by staying time delay in a super screen. The design results, separation screen were able to know that small and larger particles are conspicuous difference each motion character according to trajectory particles, and small particles raise the probability in classifying tilt plates.

• Journal of Korean Society of Environmental Engineers
• /
• v.32 no.10
• /
• pp.928-935
• /
• 2010

A bag filter system was partially burnt down during a trial run of waste wood incineration boiler. This brought about unburned hydrocarbon which caused a rapid deactivation of low temperature SCR catalyst set up in two stage after the bag filter. The deactivated catalyst was investigated in order to trace the origin by several characterization methods such as XRD, EDX, BET, TGA, SEM. The deactivated catalyst was regenerated by different methods such as acid washing, water washing in ultrasonication, and calcination treatment under air condition. It is found the calcination treatment under air condition at $450^{\circ}C$ for 2 hours to be the best regeneration method. The catalytic activity was measured in the form of 2 cm ${\times}$ 2 cm ${\times}$ 10 cm (catalyst weight 10 g) honeycomb type. A deNOx efficiency of the regenerated catalyst showed 100% at $180^{\circ}C$ which is the same level of fresh one.

• Proceedings of the Korean Institute of Resources Recycling Conference
• /
• 2006.05a
• /
• pp.78-85
• /
• 2006

In textile industries, waste effluent containing zinc is generated during the manufacture of rayon yarn from the wood pulp or cotton linters. Due to the strict environmental regulations and the presence of toxic metallic and other constituents, the discharge of industrial effluents in the sewage or disposal of solid sludge as landfill is restricted. Before recycling of zinc as zinc sulphate solution to the spinning-bath of the rayon manufacturing plant the zinc sulphate solution must be free from calcium, which is deleterious to the process as gypsum precipitates with the increase in concentration and forms scale in the bath. In the present work an attempt has been made to develop a process following solvent extraction technique using thiophosphinic extractants, Cyanex 272 and 302 modified with isodecanol and diluted in kerosene to recover zinc from rayon effluent. Various process parameters viz. extraction of zinc from different concentration of solution, distribution ratio, selective extraction, O/A ratio on extraction and stripping from the loaded organic, complex formation in the organic phase etc. have been studied to see the feasibility of the process. The extractant Cyanex 302 has been found selective for the recovery of 99.99% of zinc from the effluent above equilibrium pH 3.4 maintaining the O/A ratio of 1/30 leaving all the calcium in the raffinate. It selectively extracted zinc in the form of complex $[R_{2}Zn.3RH]_{org}$ and retained all the calcium in the aqueous raffinate. The zinc from the loaded Cyanex 302 can be stripped with 10% sulphuric acid at even O/A ratio of 10 without affecting the stripping efficiency. The stripped solution thus obtained could be recycled in the spinning bath of the rayon plant. The raffinate obtained after the recovery of zinc could be disposed safely without affacting environment.

• Journal of Korea Technical Association of The Pulp and Paper Industry
• /
• v.46 no.5
• /
• pp.69-78
• /
• 2014

The paper recycling becomes more important technology in terms of the reduction of the municipal waste and of saving natural resource such as wood. However the more utilization of recycled fiber would result in the higher contaminants in the papermaking processes and in the deterioration of the paper quality. The oil marks in the paper products becomes one of the major defects of paper products originated from paper recycling. The coagulation of various stickies in recycled fiber stock led to the oil marks. In this work, we applied functional polymer additives such as the dispersing agents, the fixing agents and the hydrophobic talc powder for the control of those stickies in order to remove the oil marks. The addition of the talc powder showed the great reduction in the oil marks of the packaging paper products. The hydrophobic surface of the talc particles collected the individual sticky materials and prevented their aggregation in the recycled fiber stock, which resulted in the great reduction of the oil marks on the paper products.

• Resources Recycling
• /
• v.30 no.4
• /
• pp.46-53
• /
• 2021

Biomass can be considered as chemical energy obtained from nature, and includes all living organisms such as plants, animals, and microorganisms. Biomass is eco-friendly, is easily obtainable from the environment, and can be recycled without special treatment processes. Biomass can also be converted into bioenergy fuel through pyrolysis and fermentation. Therefore, it has been considered as a renewable energy source, which prevents the depletion of natural resources such as fossil fuels. In this study, torrefaction to increase the carbon content in various types of biomass sources (sawdust, rice straw, rice bristles, coffee ground, and waste wood) was conducted under an inert atmosphere and at a temperature of 523~573K. The possibility of using torrefied biomass as an alternative to solid fuel for industrial purposes was analyzed by examining the carbon concentration and combustion behaviors.

• Journal of the Korean Recycled Construction Resources Institute
• /
• v.10 no.3
• /
• pp.321-326
• /
• 2022

In this study, cogeneration power plants that use biomass as a raw material to convert them into energy have recently received a lot of attention worldwide and are gradually increasing in South Korea. Therefore, in order to confirm the possibility of using the generated floor material as a fine aggregate for concrete, properties and stability evaluation experiments were performed. Compared to standard sand, the compressive strength of wood chip aggregate was improved by 11 % to 111 %, the length change rate was 89 %, and the waste processing test results met all criteria for hazardous substances. All of these are satisfied, and it is judged that the floor materials by the cogeneration power plant can be used as a fine aggregate for concrete.

• Journal of Fashion Business
• /
• v.26 no.2
• /
• pp.15-27
• /
• 2022

The purpose of this study is to perform research of ecology concepts expressed in fashion and to propose a new ecology fashion design based on the results. As a specific research method, first, to determine the concept of ecology, the contents related to ecology were extracted and organized through literature research, and then a fashion collection research was conducted to acquire basic design data, such as silhouettes, materials, details, and colors. From WGSN, and a total of 57 images were selected and used as basic data for the design suggestions. As a result of collecting the collection images, it was found that cotton or denim fabrics were mainly used, and in particular, the frequency of use was high mainly for bright tones. The use of chambray, lace, and wrinkles, was also frequent, and the use of expression techniques using burn-out, bleach, and bleaching effects or parts, or entire dyeing was often noticeable. The colors showed neutral and pastel-toned characteristics, and the silhouette was mainly composed of long silhouettes centered on maxi, such as a top or calf based on the knee, rather than a mini. Fabrics for the final designs were linen and sappan wood, and they were used for the dye and red was used as the overall color. The silhouettes were simplified, and care was taken to prevent unnecessary waste, such as paper or materials, from being generated during the production stage. We tried to achieve the purpose of eco-logy by refraining from excessive trimming, except for essential subsidiary materials, such as zippers.

• Journal of the Korean Wood Science and Technology
• /
• v.5 no.1
• /
• pp.3-8
• /
• 1977

A bark comprises about 10 to 20 percents of a typical log by volume, and is generally considered as an unwanted residue rather than a potentially valuable resource. As the world has been confronted with decreasing forest resources, natural resources pressure dictate that a bark should be a raw material instead of a waste. The utilization of the largely wasted bark of genus Quercus grown in Korea can be enhanced by learning its anatomical structure and properties. In this paper, bark characteristics of Quercus grown in Korea are described. In bark anatomy, general features such as color of rhytidome, exfoliating form, color of periderm, arrangement of periderm, and thickness of the inner and outer hark. etc., arc discussed. Studies on the microscopic structure include sieve tube, companion cell, parenchyma, pholem fiber, ray, periderm(phelloderm, phelloogen, phellem), sclereid, and crystal, etc. The results may be summarized as follows: 1. In general characteristics of rhytidomes, exfoliating is not easy and sclereids are distint to the naked eye. Inner bark is thicker than that of outer bark except in case of Q. variabilis. 2. It is not clear to distinguish between phelloderm and phellogen in Quercus bark. The phellem is developed conspicuously in Q. variabilis but that of Q. accutissima is composed of thinwalled phellem and thickwalled stone cell. 3. Quercus Bark has sieve tube, companion cell, phloem fiber and sclereid. Sclereids of Quercus bark are the most distinguished characteristics comparing with pinus and populus. The volume percent of sclereids are higher than that of fiber. 4. Rays are 1~3 seriate, and multiseriate ranging with from 15 to 20. 5. Parenchyma cell contains two types, polygonal and druses crystal.

• Journal of Korean Society of Forest Science
• /
• v.40 no.1
• /
• pp.63-69
• /
• 1978

A bark comprises about 10 to 20 percents of a typical log by volume, and is generally considered as an unwanted residue rather than a potential1y valuable resourses, As the world has been confronted with decreasing forest resources, natural resources pressure dictate that a bark should be a raw material instead of a waste. The utilization of the largely wasted bark of genus Pinus, Quercus, and Populus grown in Korea can be enhanced by learning their chemical properties. However, the chemical study of tree bark grown in korea have never been undertaken. In the present paper, the studies on the chemical properties of bark comprise carbohydrates, lignin, and extractives, composition of reducing sugars and five essential elements. The results may be summarized as follows: 1. Bark are much richer in quantity of lignin and extractives than the corresponding wood, and are chiefly consisted of lignin, extractives and carbohydrates orderly. It is the same with ash contents. Alcohol-benzene extractives of populus bark are the highest among three genus. 2. Although glucose constitutes the major sugar in both pine and hardwoods bark, in pinus, arabinose and xylose are the next but in hard woods, the next is xylose. 3. Essential elements, Ca and Kjeldahl-N are higher in the bark than in the wood. Ca content is the highest among others, and N,K followed it. Essential elements are higher in Quercus than in Populus and pinus.