• Title, Summary, Keyword: rice husk

Search Result 195, Processing Time 0.046 seconds

Manufacturing and Characterization of Pulp Mold with Rice Husk Fiber (왕겨섬유를 포함한 펄프몰드 제조 및 특성 평가)

  • Kim, Hyung Min;Sung, Yong Joo;Park, Young Seok;Shin, Jea Chul
    • Journal of Korea Technical Association of The Pulp and Paper Industry
    • /
    • v.48 no.3
    • /
    • pp.66-72
    • /
    • 2016
  • The applicability of rice husk fiber as a raw material for eco-friendly pulp mold was evaluated in this study. The higher demand of environmental friendly packaging material resulted in the more interest for the natural fiber based pulp mold. The rice husk which is an abundant agricultural byproduct in Asia could be defiberized by an alkaline digestion process. The changes in the pulp mold making process and the properties of pulp mold by the addition of the rice husk were investigated. The addition of rice husk fiber to the pulp mold made with OCC or UBKP resulted in the increase in drainage at the pulp mold forming process. In case of UBKP pulp mold, the addition of rice husk fiber increased the drying efficiency after pulp mold forming since the structure of pulp mold became more bulkier by the addition of the rice husk fiber. Those results showed the rice husk fiber could be applied to the pulp mold manufacturing as one of the eco-friendly natural fiber resources.

Durability Performance of Concrete using Rice Husk Ash

  • Jeong, Euy-Chang;Shin, Sang-Yeop;Kim, Young-Soo
    • Journal of the Korea Institute of Building Construction
    • /
    • v.13 no.2
    • /
    • pp.139-147
    • /
    • 2013
  • The purpose of this study was to investigate the durability performance of concrete that includes rice husk ash. Chloride diffusion coefficient obtained through a rapid chloride penetration test and depth of $CO_2$ penetration obtained through a rapid carbonation test were used to evaluate latent durability. Durability characteristics for rice husk ash replacement and age were determined. Through the experiment, it was found that when the replacement ratio of rice husk ash was increased from 0% to 10%, the compressive strength of concrete containing rice husk ash was similar to that of concrete containing silica fume. This shows that the durability performance of concrete containing rice husk is excellent compared to other concretes containing admixtures.

A Study on Improving the Strength Properties of Adobe Brick with the use of Agriculture Waste Stabilizer

  • Sasui, Sasui;Kim, Gyu-Yong;Lee, Sang Kyu;Son, Min-Jae;Hwang, Eui-Chul;Nam, Jeong-Soo
    • Proceedings of the Korean Institute of Building Construction Conference
    • /
    • /
    • pp.25-26
    • /
    • 2019
  • The construction of adobe houses in flood prone areas is a common practice. These houses collapse when hydraulic loads from flood exerts on the houses. The failure occurs because the adobe brick lacks strength. In order to improve strength of adobe brick, the effects of agriculture waste therefore rice straw, rice husk and rice husk ash as a stabilizing agent have been explored in this paper. The compressive strength test and splitting test was conducted on the adobe specimens which were stabilized with 2% rice straws, 2% rice husk and 2% rice husk ash by the dry weight of soil. The results showed the improvement in strength and elasticity of specimens containing rice straws & rice husk. Whereas with the addition of rice husk ash, the adobe loses its strength and showed plastic behavior.

  • PDF

Flow Behavior and Mixing Characteristics of Rice Husk/Silica Sand/Rice Husk Ash (왕겨/모래/왕겨 회재의 유동 및 혼합 특성 연구)

  • Kim, Bo Hwa;Seo, Myung Won;Kook, Jin Woo;Choi, Hee Mang;Ra, Ho Won;Yoon, Sang Jun;Mun, Tae Young;Kim, Yong Ku;Lee, Jae Goo;Rhee, Young Woo
    • Korean Chemical Engineering Research
    • /
    • v.54 no.4
    • /
    • pp.533-542
    • /
    • 2016
  • We investigate fluidization characteristics of the mixture of rice husk, silica sand and rice husk ash as a preliminary study for valuable utilization of rice husk ash obtained from gasification of rice husk in a fluidized bed reactor. As experiment valuables, the blending ratio of rice husk and sand (rice husk: sand) is selected as 5:95, 10:90, 20:80 and 30:70 on a volume base. Rice husk ash was added with 6 vol% of rice husk for each experiment and air velocity to the reactor was 0~0.63 m/s. In both rice husk/sand and rice husk/sand/ash mixture, the minimum fluidization velocity (Umf) is observed as 0.19~0.21 m/s at feeding of 0~10 vol.% of rice husk and 0.30 m/s at feeding of 20 vol.% of rice husk. With increasing the amount of rice husk up to 30 vol.%, $U_{mf}$ can not measure due to segregation behavior. The mixing index for each experiment is determined using mixing index equation proposed by Brereton and Grace. The mixing index of the mixture of rice husk/sand and rice husk/sand/ash was 0.8~1 and 0.88~1, respectively. The optimum fluidization condition was found for the good mixing and separation of rice husk ash.

Production of Carbonized Rice Husk by a Cyclone Combustor (III) (사이클론 연소기를 이용한 탄화왕겨의 제조 (III))

  • 김원태;노수영
    • Journal of Biosystems Engineering
    • /
    • v.25 no.3
    • /
    • pp.187-194
    • /
    • 2000
  • One of effective utilization technique of rice husk is known to carbonize it for using as the culture materials. A series of study on the production of carbonized rice husk by a cyclone combustor shows that the carbonized rice husk produced have a strong alkalinity. Therefore, carbonized rice husk produced by a cyclone combustor is required to neutralize with proper normality. This work is the third part of a series on the production of carbonized rice husk by a cyclone combustor. In this work, the development of neutralization process was carried out in the range of experimental conditions recommended in the previous study. Those include the preheat temperature of combustion chamber of T1b=1273∼1373K, equivalence ratio =1.68∼2.17, auxiliary gas flow rates Qg=5.15∼6.43$\ell$/min. The injection technique of dilute acid was employed for neutralization. At the lower position of the outside of combustor, a dilute nitric acid selected as neutralization liquid was injected to the carbonized rice husk exhausted from the combustion chamber. The normalities of dilute nitric acid were varied to 0.01, 0.03 and 0.05N, respectively. The injection flow rates of the solution were changes from 1.7∼4$\ell$/min. The required carbonized and neutralized rice husk could be obtained at the dilute nitric acid with normality of 0.3N and flow rate of dilute nitric acid of 2∼3.5$\ell$/min. However, the carbonized and neutralized rice husks of about 10∼20% were destroyed by spray with high injection pressure.

  • PDF

Evaluation of Biological Activities of Rice Husk Extracts

  • Kim, Dae-Jung;Oh, Sea-Kwan;Chun, A-Reum;Yoon, Mi-Ra;Hong, Ha-Cheol;Choi, Im-Soo;Lee, Jun-Soo;Yu, Kwang-Won;Kim, Yeon-Kyu
    • Preventive Nutrition and Food Science
    • /
    • v.16 no.2
    • /
    • pp.179-183
    • /
    • 2011
  • This study was conducted to determine the biological activities of 70% ethanol extracts from rice husks of nine rice cultivars in Korea. The relative antioxidant activities of rice husk extracts were evaluated by determining DPPH, ABTS radical scavenging activity and reducing power. The contents of total polyphenol, flavonoid and r-oryzanol were measured by spectrophotometric methods. Among the extracts of rice husks, Nokmi rice husks tended to have the most effective antioxidant activities compared to other rice husk varieties. Seolgaeng rice husk extract showed anti-proliferative activity against cancer cell lines (MCF7 and NCI-H460), and Hongjinju rice husk extract significantly exhibited mitogenic activity.

Exploiting the Potentials of Rice Husk Ash as Supplement in Cement for Construction in Nigeria

  • Akindahunsi, Akindehinde Ayotunde;Alade, Oluwotosin
    • International Journal of Concrete Structures and Materials
    • /
    • v.4 no.1
    • /
    • pp.3-8
    • /
    • 2010
  • This paper present the results of investigation on the use of rice husk ash as a partial substitute for cement in construction. One hundred and eighty specimens of concrete cubes were cast. 0, 5, 10, 15, and 20% partial replacement of cement with rice husk ash were carried at 1:2:4 mixes by weight with 0.60, 0.65, 0.70 water/cement ratio. The results indicated that compressive strengths of cubes at 0.6, water/cement were higher than 0.65 and 0.70. Also 5% partial replacement cement with rice husk ash at $28^{th}$ day average compressive strength value of $25.4\;N/mm^2$ compared well with 0% partial replacement of cement with rice husk ash of $26.28\;N/mm^2$. This shows that at 5% partial replacement of cement with rice husk ash can be used for structural concrete and at 15% replacement or more it can be used for non - structural construction works or light weight concrete construction. The cost analysis shows substantial amount of savings for the country.

The Effects of Operational and Mechanical Factors on the Performance of Rice-Husk Furnace (왕겨연소기(燃燒機)의 성능(性能)에 영향(影響)을 마치는 설계(設計) 및 작동인자(作動因子)에 관(關)한 연구(硏究))

  • Park, Seung Je;Noh, Sang Ha
    • Journal of Biosystems Engineering
    • /
    • v.8 no.2
    • /
    • pp.39-48
    • /
    • 1983
  • This study was performed to obtain the basic data which could be used for the modification of the manual center-burner-type rice-husk furnace into a small scale automatic type for the multi-purpose use in the farm. For this purpose, first, the utilization feasibility of the rice-husk furnace in the farm was analyzed briefly in aspects of available amount of rice-husk for the fuel, annual operation time and replaceble amount of residential heating energy with rice-husk in the farm. For the experiment a prototype furnace geared with an automatic feeding device was fabricated, and feed rate, mold size and chimney height were changed to investigate the combustion efficiency of rice-husk and thermal efficiency of the furnace. Also, optimum and limiting operational factors were observed in each treatments. The results obtained are summarized as follows. 1. If the rice-husk is intensively used for residential heating in the farm for winter season, on an average 51 percent of the total heating energy can be replaced with the rice-husk. Therefore, development of a small scale automatic rice-husk furnace was recognized to be feasible. 2. The operational condition depending on husk-feed rates was very important factor for successive steady burning operation of the given furnace. When the feed-rate was 1.5 kg/hr, the top of the burning zone should be kept at the position about 55 cm from the bottom of the combustion chamber with the periodic removal of ash (termed as steady state position), which was 18 cm above the mold waist. When the feed rates were 2.4 kg/hr and 3.0 kg/hr, the steady state position was at about 4 cm above the mold waist. 3. The mold size affected inflow rate of air into the furnace and consequently CO content in the exhaust gas. The relatively bigger mold gave positive effect on the air-inflow rate. 4. When the husk-feed rates were 1.5 kg/hr, 2.4 kg/hr, 3.0 kg/hr, the combustion efficiencies of the rice-husk were 98.5%, 97.4% and 95.0%, the thermal efficiencies of the furnace were 93.4%, 93.2% and 87.6%, and CO content in the exhaust gas were 1.21%, 1.03%, and 2.43%, respectively. The air-inflow rates were decreased with the increase of feed rates. When the amount of excess air was 30-40%, the CO content in the exhaust gas was at the minimum level. 5. When the chimney height was lowered from 260 cm to 96 cm, the air-inflow rate was slightly decreased, but the average temperature in the combustion chamber, CO content in the exhaust gas and combustion and thermal efficiencies were not changed significantly. 6. The incidental problems associated with the protytype furnace were accumulation of the ash inside the mold, accumulation of the cinder between the outer-drum of the furnace and the combustion chamber wall, and accumulation of the cinder in the chimney.

  • PDF

Chemical and Physical Characteristics of Expanded Rice Husk Medium on Growth of Rice Seedling

  • Ko Jonghan;Ham Jin Kwan;Kim Yong Bok;Kim Kyung Hee;Lee Byun Woo;Lee Youn Su
    • KOREAN JOURNAL OF CROP SCIENCE
    • /
    • v.50 no.2
    • /
    • pp.120-124
    • /
    • 2005
  • Expanded rice husk (ERR) is different from commercial rice seedling media in chemical and physical properties such as pH, permeability, and water content. This study was conducted to test a possibility of improving rice seedling growth by improving the texture of ERR as a rice seedling medium. The seedling media used were a commercial seedling medium (CSM), rice husk, and ERR 1, 2, 3, and 4 with different expansion degrees. The pH of the ERHs ranged from 6.3 to 6.8. As the expansion rate increased, ERR particle sizes decreased, and water permeability and absorption rates improved. No significant differences in shoot dry weight and rate of maturity were found among the seedlings cultivated in the different ERH media. However, the mat formation of seedling roots became loose as the expansion rates were decreased. Further studies are necessary to determine the cause of poor root growth in ERH media.

An Experimental Study on the Characteristics of Concrete Containing Rice Husk Ash (왕겨재를 혼입한 콘크리트의 특성에 관한 실험적 연구)

  • 배수호;윤상대;박광수;신의균
    • Proceedings of the Korea Concrete Institute Conference
    • /
    • /
    • pp.70-76
    • /
    • 1996
  • The purpose of this study is to investigate workability and strength of concrete containing rice husk ash. For this purpose, concrete with and without rice husk ash were tested and analyzed on the workability and the characteristics fo their strength such as compressive, tensile and flexural strength according to unit weight of binder. Also, performances of rice husk ash as an admixture of concrete were compared with those of silica hume being widely used for high-strength concrete. As a result, workability and strength of rice husk ash as an admixture of concrete were analogous to those of silica hume.

  • PDF