Experimental Study on Oil Separation from Fry-dried Low-rank Coal

엄태인,채종성,임재호,문승현 한국청정기술학회 2013 청정기술 Vol.19 No.1

Low-rank coal with high water content (32.3 wt%) was dried by fry drying, and the fuel characteristics of the dried coal from which the oil was separated by using a high-speed centrifugal separator were analyzed. After fry drying for 6 min and 10 min, the water content decreased to 5.0 wt% and 4.2 wt% respectively. The higher calorific value (HCV) of the coal increased remarkably after fry drying, from 11,442.0 kJ/kg-wet. The oil content of the fry-dried coal was 15.0 wt% and it decreased with an increase in the reheating temperature: 9.7 wt% at 80 ℃ to 9.3 wt% at 100 ℃, and then to 8.5 wt% at 120 ℃. The recovered oil could then be reused. According to of thermogravimetric analysis (TGA), there was no difference in the weight loss patterns of the coal samples with different coal diameters at a reheating temperature of 120 ℃. This was because the amount of oil separated by the centrifugal separator was affected by the reheating temperature rather than the coal diameter. And derivative thermogravimetry (DTG) curves of raw coal before the fry-drying process, a peak is formed at 400 ℃ in which the volatile matter is gasified. In case of the fry-dried coal, the first peak is generated at 350 ℃, and the second peak is generated at 400 ℃. The first peak is caused by the oil that is replaced with the water contained in the coal during the fry-drying process. Further, the peaks of the coal samples in which the oil is separated at a reheating temperature of 80 ℃, 100 ℃, 120 ℃, respectively are smaller than that of the coal in which the oil is not separated, and this is caused by that the oil is separated by the centrifugal separator.

Experimental Study on Oil Separation from Fry-dried Low-rank Coal

Tea-In Ohm,Jong-Seong Chae,Jae-Ho Lim,Seung-Hyun Moon 한국청정기술학회 2013 청정기술 Vol.19 No.1

WHO BENEFITS FROM IMPORT SUBSTITUTION INDUSTRIALIZATION (ISI) OF THE PHILIPPINE MILKFISH HATCHERY-BRED FRY INDUSTRY?

Yolanda T. Garcia,Maria Esperanza T. Garcia,Arnulfo G. Garcia 한국무역학회 2019 한국무역학회 국제학술대회 Vol.2019 No.08

This study aims to estimate the welfare gains of the Philippine milkfish industry in establishing local fry hatcheries to reduce imports from Indonesia and Taiwan. It also seeks to establish the industry stakeholders who gain from this import substitution industrialization (ISI). The economic surplus model was used to estimate the welfare gains from ISI of hatchery-bred milkfish fry in the fishery sector. Specifically, the changes in consumer and/or producer surplus per stakeholder were compared to determine who the biggest gainers are. Results of the study showed that the consumer surplus from the milkfish fry industry was larger than its producer surplus. On the other hand, the reverse was true for the grow-out industry. It is interesting to note that the consumers in the fry industry and the producer in the grow-out industry were the same set of stakeholders, i.e., the milkfish grow-out operators, who gained the most from the ISI of the hatchery-bred fry. The study also showed that the commercialization of the local milkfish hatchery technologies can bring about more benefits to the country than importing frys and fingerlings. Hence, ISI of local hatcheries for other aquaculture species can be expected to bring similar welfare gains. More importantly, the technical and financial assistance that were extended by the government’s fishery sector through the GAINEX project as pioneered by DOST-PCAARRD can serve as an effective catalysts to prospective hatchery operators in reducing the risks, especially when setting-up a new enterprise like the hatchery-bred fry for an emerging aquaculture species in the country.

Study on the Melting Experiment of the Fry-dried Industrial Waste Water Sludges

( Jong-seung Chae ),( Su-ah Choi ),( Ho-hyun Shin ),( Tae-in Ohm ) 한국폐기물자원순환학회(구 한국폐기물학회) 2015 한국폐기물자원순환학회 3RINCs초록집 Vol.2015 No.-

From 2012, ocean dumping of the harmful organic sludge was prohibited by London protocol, and direct landfill thereof was also prohibited to prevent soil and groundwater contamination. Therefore, the organic sludge and the sewage sludge have been recycled or incinerated in public disposal equipment and contracted-out treatment equipment. However, there is a limit in the treatment due to mass-generation thereof. Therefore, the paradigm shift for the development of an eco-friendly and economical treatment technology which breaks from the existing sludge treatment method is required. It is necessary to apply a new recycling and minimization method to the organic sewage sludge, the waste water sludge and the food waste. And the drying fuelization method in which the remaining substances are dried and reused is required. Particularly, in this study, to process the organic waste water sludge with an eco-friendly and economical method, the fry-drying technology and the melting technology were used in this study. The drying characteristic and the thermal characteristic were analyzed through these technology, and the elution experiment was performed to evaluate the environmental performance of the finally vitrified slag, and the following results were obtained. 1. The fuel ratio (fixed carbon/volatile matter) of the waste water sludge after the fry-drying is 0.002 to 0.089 which is much lower than that (0.10 to 0.3) in the production of the waste solid fuel. If the dried sludge is burnt in the general burner, the possibility of generation of CO and soot is very high due to incomplete combustion of the volatile matter, and thus the two-stage combustion or recirculation combustion technique is required. The high volatile matter content is caused by the oil component contained in the fry-drying process. 2. In the result of selecting the two kinds of industrial sludges after the fry-drying and analyzing the produces eluted after the melting experiment of the selected sludges, Hg, Cd, Cr and Pb were not detected, and the As concentration is 0.007 to 0.019mg/kg. Therefore, the molten slag can be recycled as the cyclic aggregate.

Bio-solid production from sewage sludge by fry-drying and torrefaction

( Truong X. Do ) 한국공업화학회 2014 한국공업화학회 연구논문 초록집 Vol.2014 No.1

Fry-drying is a technology that sewage sludge waste is mixed with the oil and then dried in a series of evaporator. Torrefaction, also known as mild-pyrolysis, is a thermal treatment carried out at temperatures between 200 and 300°C under the atmospheric pressure in the absence of oxygen. The product of this torrefaction process is bio-solid which has much higher energy density than that of sewage sludge waste. The objective of this study is to find solutions for saving energy by modeling the fry-drying and torrefaction processes and analyzing the heating network. A comprehensive model of a existing torrefaction plant with capacity of 45 t/d was developed by using a process simulator. The research result show that it can be the promising way to increase the economic benefit of the existing torrefaction plant.

A study on the solid fuel characteristics of dried swine excreta using fry-drying technology

( Jae-ho Lim ),( Jin-hee Yun ),( Jong-seong Chae ),( Tae-in Ohm ),( Seung-hyun Moon ) 한국폐기물자원순환학회 2011 ISWA Vol.2011 No.0

We investigated the evaporative drying by immersion in hot oil(EDIHO) technology for drying swine excreta which contained 80 wt.% of water content. This drying method involved heating oil to a temperature higher than that needed for moisture to be evaporated from the swine excreta by turbulent heat and mass transfer. In this study, the EDIHO technology with the heat transfer coefficient of approximately 500 w/m²℃ at maximum was applied in drying swine excreta for using solid waste fuel. The two type oils used in the EDIHO included refined waste oil and B-C heavy oil for hot oil. The swine excreta removed the moisture by this process has high calorific value so it can be used as fuel in incinerators as well as coal and solid fuel combustors. The result of the swine excreta dried by EDIHO process at average temperature 150 ℃ of frying oil for 8 minutes are as follows: (1) regarding the drying performance of the two kinds of swine excreta, the moisture in the swine excreta from the raw swine excreta and the digested swine excreta after drying reduced from 78.9 wt.% to 1.6 wt.% (refined waste oil), 1.6 wt.%(B-C heavy oil) and 79.6 wt.% to 3.4 wt.%(refined waste oil), 3.5 wt.%(B-C heavy oil) in the swine excreta; (2) the low calorific value of the raw swine excreta and the digested swine excreta prior to drying were 2,826 kJ/kg, 2,369 kJ/kg respectively, but in increased to 32,728∼33,071 kJ/kg and 22,998∼23,689 kJ/kg after the drying. And the dried swine excreta can be used as a solid fuel owing to high heating value similar to lignite: (3) The results of TGA analysis have shown that the initial volatile, carbon and emission residual volatile combustion of the fry-drying swine excreta and raw swine excreta occurred in the range of 250 ℃∼500 ℃.

Techno-economic analysis of fry-drying and torrefaction plant for bio-solid fuel production

Do, Truong Xuan,Lim, Young-il,Cho, Hyodeuk,Shim, Jaehui,Yoo, Jeongkeun,Rho, Kyutai,Choi, Seong-Geun,Park, Chanwoo,Park, Byeong-Yun Elsevier 2018 Renewable energy Vol.119 No.-

<P><B>Abstract</B></P> <P>A total of 10 t/d of bio-solid (BS) fuel was produced from 45 t/d of organic solid waste (OSW) containing 80 wt% water using a fry-drying and torrefaction (FDT) plant. This study aimed at evaluating economic feasibility of the FDT plant in terms of the total capital investment (TCI), total production cost (TPC), return on investment (ROI) and payback period (PBP). Two different heating sources for steam generation were used: Case 1 using BS produced in this plant, and Case 2 using LNG provided externally. A four-level economic potential approach was applied to evaluate economic feasibility. A sensitivity analysis was conducted to determine the major factors influencing ROI. Case 1 using BS showed a higher ROI than Case 2 using LNG because the LNG cost overwhelmed the TCI increment of Case 1. For Case 1 with 45 t/d of OSW, the TCI, TPC, ROI and PBP were $3.6 million, $1.3 million/yr, 6.0%/yr and 9.8 yr, respectively. To achieve a desired ROI of 10%/yr, the plant sizes of Cases 1 and 2 were 60 and 90 t/d, respectively. When the OSW treatment credit increased from 100 $/t to 120 $/t, ROI exceeded 10% in Case 1 with 45 t/d.</P> <P><B>Highlights</B></P> <P> <UL> <LI> 10 t/d bio-solid (BS) was produced from 45 t/d of organic sludge by fry-drying plant. </LI> <LI> Economic feasibility was evaluated based on a four-level economic potential approach. </LI> <LI> Fry-drying plant using BS as a heating source was more efficient than that using LNG. </LI> <LI> The minimum plant size required to achieve a return on investment of 10% was 60 t/d. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

슬러지 유중 건조에 대한 전산 해석 및 실험적 연구

신미수(Mi Soo Shin),김혜숙(Hey Suk Kim),김병갑(Byeong Gap Kim),황민정(Min Jeong Hwang),장동순(Dong Soon Jang),엄태인(Tae In Ohm) 大韓環境工學會 2010 대한환경공학회지 Vol.32 No.4

유중 건조 공정의 기본 원리는 수분과 비열차이가 있는 오일을 가열할 때 온도 차이에 따라 형성되는 슬러지 내부의 급격한 압력 변화를 이용한다. 즉 슬러지 내부에 발생하는 급격한 압력 상승이 이루어질 때 슬러지 공극을 통하여 수분이 빠르게 배출하도록 하는 것이다. 본 연구의 목적은 유중 건조공정 중 다양한 운전 변수가 건조효율에 미치는 영향을 구체적으로 규명하기 위한 것이다. 변수 연구를 위하여 일련의 건조 실험과 수치해석을 시도하였으며 그 결과 건조온도, 건조시간, 폐오일종류, 슬러지 종류 등 중요 실험변수에 따른 건조곡선이 얻어졌다. 건조 온도 변화에 따른 연구 결과는 폐오일의 종류에 관계없이 140℃ 이상으로 운전하는 것이 건조효율에 유리한 것으로 나타났으며 이 결과는 수치 해석적 결과로도 확인되었다. 그리고 슬러지 직경의 경우 직경이 감소할수록 효율적으로 건조되는 경향으로 보였으며 이는 비표면적의 증가에 기인하는 것으로 판단되었다. 오일 종류나 물성의 변화에 대한 연구에서는 오일의 점도가 가시적인 영향을 주는 것으로 나타났다. 특히 점도가 높은 오일의 경우 건조 초반에 수분 증발이 현저히 지체되는 현상이 나타났다. 그러나 건조온도 140℃ 이상에서는 이러한 지체 현상이 감소하는 결과를 나타내었다. 슬러지 종류에 따른 연구에서는 전체적으로 큰 차이를 나타내지는 않았으나 하수슬러지가 다른 종류의 슬러지에 비하여 좀 더 가시적으로 양호한 수분제거 양상을 나타내었다. 수치 해석적 연구는 실험적 연구에 대한 상호보완적인 연구로서 가능성을 보였으나 복잡한 세부모델에 대한 경험적인 모델개발의 필요성이 제기되었다. The basic principle of fry drying process of sludge lies in the rapid pressure change of sludge material caused by the change of temperature between oil and moisture due to the difference of specific heat. Therefore, the rapid increase of pressure in drying sludge induces the efficient moisture escape through sludge pores toward heating oil media. The object of this study is to carry out a systematic investigation of the influence of various parameters associated with the sludge fry drying processes on the drying efficiency. To this end, a series of parametric experimental investigation has been made together with the numerical calculation in order to obtain typical drying curves as function of important parameters such as drying temperature, sludge diameter, oil type and sludge type. In the aspect of frying temperature, especially it is found that the operation higher than 140℃ was favorable in drying efficiency regardless of type of waste oil employed in this study. The same result was also noted consistently in the investigation of numerical calculation, that is, in that the sludge particle drying was efficiently made over 140℃ irrespective of the change of particle diameter. As expected, in general, the decrease of diameter in sludge was found efficient both experiment and numerical calculation in drying due to the increased surface area per unit volume. In the investigation of oil type and property, the effect of the viscosity of waste oil was found to be more influential in drying performance. In particular, when the oil with high viscosity, a visible time delay was noticed in moisture evaporation especially in the early stage of drying. However, the effect of high viscosity decreased significantly over the temperature of 140℃. There was no visible difference observed in the study of sludge type but the sewage sludge with a slightly better efficiency. The numerical study is considered to be a quite useful tool to assist in experiment with more detailed empirical modeling as further work.

Process calculation of fry-drying combined with steam compression for efficient fuel production from sewage sludge

( Sung Pyo Hong ),( Changkook Ryu ),( Han Seo Ko ),( Jong Seong Chae ),( Tae In Ohm ) 한국폐기물자원순환학회(구 한국폐기물학회) 2011 한국폐기물자원순환학회 추계학술발표논문집 Vol.2011 No.-

Characterization and application of a coating of starch extracted from avocado (Persea americana L. cv. Hass) seeds as an alternative to reduce acrylamide content in French fries

O. Vega-Castro,M. Ramírez,L. Blandón-Mena,J. Contreras-Calderón,M. Mesías,C. Delgado-Andrade,F. J. Morales,D. Granda-Restrepo 한국식품과학회 2022 Food Science and Biotechnology Vol.31 No.12

The starch extracted from avocado (Persea americana L. cv. Hass) seeds was characterized and used in the preparation of an edible coating to reduce the oil uptake and acrylamide content in French fries. Starch characterization was carried out using Differential Scanning Calorimetry, Fourier transform infrared spectrophotometry, gelatinization, and scanning electron microscopy. Uncoated (UFF) and coated (CFF) French fries were compared and evaluated for moisture, water activity (Aw), fat, color, firmness, acrylamide content, and sensorial analysis. The extracted starch presented a high crystalline structure and good stability to mechanical work and heat treatments. The CFF French fries showed significantly higher Aw, color parameter a*, but lower luminosity and acrylamide content than UFF samples. Similarly, the CFF samples tended to decrease the fat content, although without statistical differences. Avocado seed starch can be an economical and technically feasible alternative to the food industry as an effective coating to reduce acrylamide content in French fries.