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All Journal Pelita Perkebunan Planta Tropika
Widjaya, Dani
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Agriculture, Biological Sciences & Forestry

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Utilization of Several Agricultural Wastes into Briquette as Renewable Energy Source Widjaya, Dani; Sinatrya, Almansyah Nur; Kusumandaru, Wahyu; Jupriyanto, Ahmad; Nijkamp, Randy Trinity
PLANTA TROPIKA Vol 10, No 2 (2022)
Publisher : Department of Agrotechnology, Universitas Muhammadiyah Yogyakarta

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.18196/pt.v10i2.13773

Abstract

Tobacco stems contain 56.10% cellulose content, 15.11% lignin, 22.44% hemicellulose, and 44.61% total organic carbon, which can be used as a source of energy or fuel. This study aimed to utilize tobacco stems in a briquette form as alternative energy. The materials used in this study were tobacco stem waste, rice husk, wood charcoal, and coconut shell. The treatments used in this study consisted of T1 (100% of tobacco stems), T2 (80% of tobacco stem + 20% of coconut shell), T3 (80% of tobacco stem + 20% rice husk), and T4 (33.33% of tobacco stems + 33.33% of rice husk + 33.33% coconut shell). The fastest combustion rate was found at T3, 0.12 gram/sec, while T1 and T2 had the same combustion rate. T4, a mixture of various materials, had no significant difference compared to T1, T2, and T3. The highest calorific value of tobacco stem briquettes was in T4 (4127 Kcal/kg), and the lowest was in T1 (2343 Kcal/kg). The combustion rate of these tobacco stem briquettes was longer than that of charcoal briquettes, whose average burning rate is 0.234 grams/second. Overall, this study provides an overview of the best combination to create briquettes from agricultural waste.
Mapping coffee base countries in the world: Case studies from three continents (Africa-America-Asia). Widjaya, Dani; Yanuarti, Rizky
Pelita Perkebunan (a Coffee and Cocoa Research Journal) Vol. 40 No. 1 (2024)
Publisher : Indonesian Coffee and Cocoa Research Institute

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22302/iccri.jur.pelitaperkebunan.v40i1.593

Abstract

The agricultural sector has an important role in the world economy, including the coffee commodity in the plantation subsector. More than 80 countries on the continents of Africa, America and Asia produce coffee and involve more than 100 million people in the process. The growth rate of coffee on these three continents also shows positive values. The aim of this research is to map the countries that are the basis for coffee in the world and look at the prospects for coffee in these countries. The novelty of the research lies in comparing coffee production during the 2017-2022 period in coffee producing countries on three continents, namely Africa, America and Asia. The analysis used to achieve research objectives is Location Quotient (LQ), Dynamic Location Quotient (DLQ) analysis and a combination of both. The research results show that there are 28% of countries on the African continent that have LQ values ​​> 1, 31% on the American continent and 16% on the Asian continent. The DLQ value which shows the prospects for coffee commodities in the future can be seen that on the African continent there are 10 countries that have a DLQ value > 1, while on the American continent there are 13 countries and on the Asian continent there are 9 countries. The American continent has more countries in the Mainstay category (39%), compared to other continents, this indicates that the prospects for coffee commodities on the American continent are quite good in the future.
Utilization of Several Agricultural Wastes into Briquette as Renewable Energy Source Widjaya, Dani; Sinatrya, Almansyah Nur; Kusumandaru, Wahyu; Jupriyanto, Ahmad; Nijkamp, Randy Trinity
PLANTA TROPIKA Vol. 10 No. 2 (2022)
Publisher : Department of Agrotechnology, Universitas Muhammadiyah Yogyakarta

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.18196/pt.v10i2.13773

Abstract

Tobacco stems contain 56.10% cellulose content, 15.11% lignin, 22.44% hemicellulose, and 44.61% total organic carbon, which can be used as a source of energy or fuel. This study aimed to utilize tobacco stems in a briquette form as alternative energy. The materials used in this study were tobacco stem waste, rice husk, wood charcoal, and coconut shell. The treatments used in this study consisted of T1 (100% of tobacco stems), T2 (80% of tobacco stem + 20% of coconut shell), T3 (80% of tobacco stem + 20% rice husk), and T4 (33.33% of tobacco stems + 33.33% of rice husk + 33.33% coconut shell). The fastest combustion rate was found at T3, 0.12 gram/sec, while T1 and T2 had the same combustion rate. T4, a mixture of various materials, had no significant difference compared to T1, T2, and T3. The highest calorific value of tobacco stem briquettes was in T4 (4127 Kcal/kg), and the lowest was in T1 (2343 Kcal/kg). The combustion rate of these tobacco stem briquettes was longer than that of charcoal briquettes, whose average burning rate is 0.234 grams/second. Overall, this study provides an overview of the best combination to create briquettes from agricultural waste.
Variability of factors influencing coffee export performance in Indonesia. Yanuarti, Rizky; Widjaya, Dani
Pelita Perkebunan (a Coffee and Cocoa Research Journal) Vol. 39 No. 3 (2023)
Publisher : Indonesian Coffee and Cocoa Research Institute

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22302/iccri.jur.pelitaperkebunan.v39i3.556

Abstract

Abstract Empirical evidence is lacking on the nexus between coffee commodity output and commodity price volatility of developing countries especially during pandemic era. The most visible impact from an economic perspective is the change of price expectation on people's basic needs which are in line with the decline of economic growth in Indonesia. This has significant implications, particularly considering the important role of coffee in supporting the country's economy. The aim of this study is to examine the factors that influence the performance of coffee exports in Indonesia. The novelty of this study lay on the used national dataset within the range of 20 years (2000-2020) and including the pandemic effect on coffee sector performance. We examines the relationship between variables and coffee exports in Indonesia using unit root tests, cointegration analysis, and an Error Correction Model (ECM). The results show that coffee exports, total area, coffee production, coffee price, gross national income, and coffee imports have significant influences on coffee exports. The variables of total area and coffee production impact coffee exports negatively in the long term, while coffee price, gross national income, and coffee imports have mixed effects. In the short term, total area and coffee production significantly affect coffee exports, while coffee prices and gross national income show no significant impact. Coffee imports have a significant negative influence on coffee exports in the short term. These findings contribute to understanding the dynamics of the coffee industry in Indonesia.
Co-Authors Jupriyanto, Ahmad Kusumandaru, Wahyu Randy Trinity Nijkamp Sinatrya, Almansyah Nur Yanuarti, Rizky