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2026 Vol.58, Issue 4 Preview Page

Original Paper

Preparation of Granular Biochar from Citrus Pomace

감귤박 기반 입상형 바이오차 제조 연구

Myeong Ho Lee1
,
So Hyun Kim1
,
Su In Cho1
,
Jong Hwan Shin2
,
Yong Joo Sung3†
이 명호1
,
김 소현1
,
조 수인1
,
신 종환2
,
성 용주3†
1Department of Biobased Materials, College of Agriculture and Life Sciences, Chungnam National University
2Department of Horticultural Crop Research, Citrus Research Center, National Institute of Horticultural and Herbal Science, RDA
3Department of Biobased Materials, College of Agriculture and Life Sciences, Chungnam National University
1충남대학교 농업생명과학대학 환경소재공학과, 학생
2농촌진흥청 국립원예특작과학원 원예작물부 감귤연구센터, 농업연구사
3충남대학교 농업생명과학대학 환경소재공학과, 교수
†Corresponding Author: E-mail: yosung17@cnu.ac.kr (Address: Department of Biobased Materials, College of Agriculture and Life Sciences, Chungnam National University, Daejeon, 34134, Republic of Korea)
30 August 2026. pp. 76-86
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Abstract

Citrus pomace is a major by-product of citrus processing; however, its utilization remains limited because of its high moisture content and low pH. In this study, granular biochar was produced by first fabricating binder-free granules using the natural binding components of citrus pomace, followed by carbonization. Citrus tree pruning residues were blended with the pomace to control moisture content and to improve granule formability and carbonization characteristics. The proposed granulation–carbonization process produced biochar with a uniform particle size and shape, which markedly improved carbonization uniformity and product consistency compared with conventional biochar prepared from irregular biomass. The quality of the resulting biochar was evaluated based on its pH and elemental characteristics, including the H/C and O/C atomic ratios, confirming that high-quality biochar can be produced through the proposed process. In addition, the granular biochar generated fewer fines, thereby improving production yield and handling properties. Incorporating inorganic additives further demonstrated the potential to produce functional biochar with adjustable pH and nutrient-supplying capability. Overall, the proposed production process provides an effective strategy for the high-value utilization of citrus processing residues, and the resulting granular biochar offers considerable potential as an environmentally friendly soil amendment.

Keywords
Citrus pomace
granular shape
carbonization
biochar
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Information
  • Publisher :Korea Technical Association of The Pulp and Paper Industry
  • Publisher(Ko) :한국펄프종이공학회
  • Journal Title :Journal of Korea TAPPI
  • Journal Title(Ko) :펄프종이기술
  • Volume : 58
  • No :4
  • Pages :76-86
  • Received Date : 2026-07-29
  • Revised Date : 2026-08-11
  • Accepted Date : 2026-08-15
  • DOI :https://doi.org/10.7584/JKTAPPI.2026.8.58.4.76
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