Totally chlorine-free bleaching of prehydrolysis soda pulp from plantation hardwoods consisting of various lignin structures

The process of prehydrolysis followed by soda-anthraquinone (AQ) cooking and totally chlorine-free (TCF) bleaching with peroxymonosulfuric acid (Psa) was investigated to develop a biorefinery process. Eucalyptus globulus, showing a high syringaldehyde (Sa) to vanillin (Va) molar ratio after nitrobenzene oxidation, was utilized. Xylooligosaccharide yield in the prehydrolysate (PHL) obtained at 150 °C for 2.5 h reached 7.2% of wood weight, indicating 47% extraction of xylan. Furfural yields increased with acid catalytic dehydration of the PHL to 1.0–1.8% of wood weight; adding an earlier acid post-hydrolysis of the PHL to generate monomeric xylose enhanced furfural production to 4.0%. Soda-AQ cooking, a non-sulfur process affording simpler alkali lignin isolation than kraft cooking, was utilized. Active alkali dosage increment decreased both Sa to Va molar ratio (S/V ratio) and Sa and Va yields of dissolved lignin. Gel permeation chromatography indicated decreased or increased purified lignin weight-average molecular weight (Mw) upon increased active alkali dosage or prehydrolysis temperature, respectively (e.g., 150 to 170 °C at 18% alkali increased Mw 1653 to 2050). Chlorine dioxide (0.083% and 0.042% as active chlorine) inclusion during the 1st and 2nd Psa stages with Psa (0.2% and 0.1% as H2SO5 weight, respectively) improved final bleached pulp viscosity from 6.0 to 7.2 mPa s

Life Cycle Assessment for Integrated Dissolving Pulp and Furfural Production from Oil Palm Empty Fruit Bunch

2020【要旨

Social-life cycle assessment of oil palm plantation smallholders in Bengkulu province, Indonesia

Smallholders are often seen as a weak point in the development of oil palm plantation production. The quality and yield of their production are considered low according to world market standards; the continuity of their production is irregular; and finally, improving the welfare of farmers is difficult to achieve. However, smallholder plantations have an important and strategic role in achieving sustainable development. This study aims to assess the social life cycle assessment of smallholder oil palm plantations in Bengkulu Province by involving stakeholders consisting of workers, local communities, farm owners, and value chain actors. A total of 600 respondents were selected using quota sampling and interviewed using a structured questionnaire. Data analysis was conducted using social-life cycle assessment, involving various social issues and relevant social indicators for each stakeholder. The findings in our research show that smallholder oil palm plantations still do not meet the minimum wage for workers, and the equipment used by workers is still very minimal in terms of security and safety guarantees. The price of palm oil continues to fluctuate, and plantation policies are constantly changing, making it difficult for oil palm owners to meet the standards and various rules that are set for managing oil palm plantations. In addition, oil palm plantations are no longer a guarantee for the fulfillment of food security conditions for household owners, workers, communities, and actors involved in the oil palm institutional chain. Our finding is that, surprisingly, there is a low level of commitment by smallholders and the government to sustainability in oil palm plantations. The Indonesian Sustainable Palm Oil and Roundtable on Sustainable Palm Oil as standards for sustainable oil palm plantations, as well as global standards for oil palm plantations to demonstrate environmentally friendly production processes, have not been able to compel smallholders to implement sustainable development in oil palm. Various policies formulated by the Indonesian government are perceived to have not addressed the core issues faced by small-scale farmers. Policies supporting small-scale farmers, particularly those related to increasing productivity, fostering and monitoring the environmental management of palm oil plantation activities, and ensuring ownership of plantation, are necessary for the achievement of sustainable smallholder palm oil plantation development

PROSES PRODUKSI BIOETANOL DARI LIMBAH CAIR GULA DALAM KAITANNYA DENGAN POTENSI SEBAGAI BAHAN BAKAR DALAM PERSPEKTIF LIFE CYCLE INVENTORY ASSESSMENT

Life cycle inventory assessment merupakan salah satu tahapan di dalam Life Cycle Assessment (LCA) yang bisa digunakan untuk menggambarkan interaksi materi dan energi di dalam suatu proses produksi bioetanol. Studi kasus dilakukan di pabrik gula kawasan Subang dan pabrik bioetanol di kawasan Palimanan yang merupakan pabrik gula dan bioetanol terbesar di Jawa Barat. Inventory yang dilakukan adalah pada bagian perkebunan tebu, pabrikasi tebu menjadi gula, transportasi dari pabrik gula menuju ke pabrik bioetanol, dan pabrikasi etanol. Luas lahan kebun tebu yang dimiliki oleh pabrik gula di Subang adalah seluas 5000 hektar. Dari bahan baku tebu 3000 ton/hari dihasilkan molase sebanyak 60 ton/hari, sisanya menjadi gula dan ampas tebu. Pada inventory kali ini selain dari sisi proses juga dilakukan inventory pada sisi transportasi

A Life Cycle Assessment of Organic and Chemical Fertilizers for Coffee Production to Evaluate Sustainability toward the Energy–Environment–Economic Nexus in Indonesia

Coffee is an important agricultural commodity that is branded according to its environmental criteria in the global market. Therefore, Indonesia’s coffee production system needs to be investigated to meet the demand for eco-labeling, which has become a consumer preference. This study aims to assess the comprehensive sustainability evaluation of coffee production nurtured by an organic fertilizing system (OFS), chemical-organic fertilizing system (COFS), and chemical fertilizing system (CFS) that focuses on the energy–environment–economic nexus. A life cycle assessment (LCA), life cycle cost analysis (LCC), and energy analysis were performed as methods to evaluate the environmental impact, economic performance, and energy requirement analysis. The results indicated that the OFS had superior performance in two sustainability aspects: resulting in the lowest environmental damage and generating the highest economic benefit. Simultaneously, COFS shows the highest sustainability performance as it consumes the least energy. In contrast, CFS indicated the lowest sustainability performance in all aspects: highest environmental impact, lowest economic benefit, and highest energy consumption. Therefore, OFS is strongly recommended to be applied broadly, considering its environmental and economic superiority. Consequently, massive OFS application was followed by higher energy consumption. Alternatively, COFS can be considered for application due to its higher energy performance, even though it can potentially result in higher environmental damage and lower economic benefit. However, the government should explicitly provide some effort for the broad application of OFS in financial and assistance support since the shifting process needs more time to adapt

Reduction in Energy Requirement and CO2 Emission for Microalgae Oil Production Using Wastewater

A comparative evaluation of energy requirement and CO2 emission was performed for native polyculture microalgae oil production in a wastewater treatment plant (WWTP). The wastewater provided nutrients for algae growth. Datasets of microalgae oil production and their details were collected from the Minamisoma pilot plant. Environmental impact estimation from direct energy and material balance was analyzed using SimaPro® v8.0.4. in two scenarios: existing and algal scenarios. In the existing scenario, CO2 emission sources were from wastewater treatment, sludge treatment, and import of crude oil. In the algal scenario, CO2 emission with microalgae production was considered using wastewater treatment, CO2 absorption from growing algae, and hydrothermal liquefaction (HTL) for extraction, along with the exclusion of exhausted CO2 emission for growing algae and use of discharged heat for HTL. In these two scenarios, 1 m3 of wastewater was treated, and 2.17 MJ higher heating value (HHV) output was obtained. Consequently, 2.76 kg-CO2 eq/m3-wastewater in the existing scenario and 1.59 kg-CO2 eq/m3-wastewater in the algal scenario were calculated. In the HTL process, 21.5 MJ/m3-wastewater of the discharged heat energy was required in the algal scenario. Hence, the efficiency of the biocrude production system will surpass those of the WWTP and imported crude oil

Microalgae Oil Production Using Wastewater in Japan—Introducing Operational Cost Function for Sustainable Management of WWTP

A comparative evaluation of economic efficiency was performed for native polyculture microalgae oil production in an oxidation ditch (OD) process wastewater treatment plant (WWTP). A cost function was developed for the process. The operational cost per 1 m3 of wastewater (w.w.) was 1.34 $/m3-w.w. in the existing scenario, 1.29$/m3-w.w. in algal scenario A (no cost for CO2 and waste heat) and 1.36 $/m3-w.w. in algal scenario B (no cost for CO2). The conditions were set as follows: hydraulic retention time (HRT): 4 days, microalgal productivity: 0.148 g/L and daily treatment volume: 81.6 m3-w.w./d. The cost differences were related to the increase in polymer flocculants for algae separation (+0.23$/m3-w.w), carbon credits from CO2 absorption (−0.01 /m3-w.w), the sales of biocrude (−0.04 /m3-w.w) and sludge disposal (−0.18 $/m3-w.w). Hence, the introduction of the algae scenario was the same cost-effective as the existing scenario. Microalgae oil production in an OD process WWTP can serve as a new energy system and reduce the environmental load in a society with a declining population