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Coal is a commonly used fuel by coal power plants that produce coal fly ash and coal bottom ash (coal FABA) as byproducts. The latest regulation in Indonesia changes coal FABA classification to non-toxic waste, which opens up its utilization possibility. This paper analyses the coal FABA potential from Suralaya Coal Power Plant as concrete material and its environmental impact. To determine coal FABA potential, the methods used in this paper are slump test, compressive strength test, flexural strength test, and carbon footprint calculation. This paper shows that concrete mixture with coal FABA content has a lower slump value, lower compressive strength, and generally lower flexural strength. Furthermore, the carbon footprint calculation result shows that concrete mixture with coal FABA content has lower CO2 emissions than conventional concrete. Finally, the result shows that concrete with coal FABA could be used as non-structural concrete. [ABSTRACT FROM AUTHOR]

Globally, the area of seagrass beds important to the ecosystems in coastal environment is decreasing due to environmental pressures, both natural and artificial. Transplantation is one way to restore the condition of damaged seagrass beds, the anchor transplant method uses the transfer of donor seagrass to the transplant area, while the seed transplant method uses seed sowed from seagrass. This study aimed to investigate the survival and growth rates of seagrass transplants and the biomass and chlorophyll content of transplanted Enhalus acoroides in the waters of Panjang Island Jepara utilizing anchor and seedling methods. The research was conducted in the waters around Panjang Island, Jepara, between September and December 2021. The results indicated that transplantation of seagrass E. acoroides using the anchor method resulted in the highest average growth rate of 0.25 cm/day and a survival rate of 96.67%, while transplantation using the seedling method resulted in a growth rate of 0.18 cm/day and a survival rate of 83.33%. The results showed that the anchor method scored better than the seedling transplantation method in terms of growth rate and survival rate. However, seedling is a feasible method to meet the availability of seeds that will later be transplanted, considering that the anchor method still has shortcomings in terms of the availability of seeds and the use of pegs which are still not environmentally friendly. So that the seedling method can be recommended for the restoration process of seagrass ecosystems by taking into account the season, weather and other important indices. [ABSTRACT FROM AUTHOR]

Every institution running the services needs to procure goods and services in running the activities. The procurement practices not only discuss the quality and value of products but also determine the environmental impact. This study identifies and evaluates factors that affected the application of Green public procurement (GPP) in hospitals and looked at the recommended solutions and response actions. Respondents selected as the object of this study were 34 people involved in the procurement process from several Indonesian government hospitals. In this study, the inhibiting factors of the application of GPP were divided into eight variables with 27 indicators. The analytical method used in this study is the PLS method. The study results indicated that two of the eight indicators significantly affected the implementation of GPP are cost and products. [ABSTRACT FROM AUTHOR]

ndonesia is one of the countries worldwide that consume significant fertilizer for agricultural activities. A total of 6.27 Mt of urea fertilizer per annum was consumed. Therefore, some fertilizer plants operate in Indonesia and one of the plants is managed by PT Pupuk Kujang. The plant is located at Cikampek West Java and has two production lanes where each lane has a production capacity of 570,000 t urea annually. This study is aimed to identify the potential impact and environmental hotspots of a fertilizer plant. The Life Cycle Assessment (LCA) method was applied and using Centrum Voor Milieuwetenschappen Impact Assessment (CML-IA) analysis for life cycle impact assessment (LCIA). Three main categories were analysed, namely climate change, acidification, and eutrophication. The functional unit was the potential environmental impacts generated by 50 kg of urea fertilizer production. The productions (ammonia, and urea) and distribution process were considered as the system boundary. Seven production processes occurred in the urea plant including synthesizing, purification, concentration, prilling, recovery, process condensate, and bagging process. The results showed that the 50 kg of urea fertilizer emitted 4.73 kg CO2-eq, 0.03 kg SO2-eq, and 0.015 kg PO4-eq and the environmental hotspots were caused by the consumption of electricity from state-owned company (31.5 %), polypropylene content in the fertilizer packaging (0.74 %), and transportation (1.48 %). These environmental hotspots provided an opportunity for the renewable energy introduction and the application of a packaging reuse program to reduce those potential environmental impacts. These strategies improved the environmental performance of PT Pupuk Kujang as a urea fertilizer producer. [ABSTRACT FROM AUTHOR]

The utilization of new and renewable energy sources explicitly based on biomass needs to be increased to reduce dependence on fossil fuels. One of the potential biomasses of plantation waste in Indonesia that can be utilized is oil palm plantation waste in the form of fronds and trunks that are converted with multi-stage downdraft gasification technology. This study aimed to conduct a technical analysis, economic analysis, investment risk analysis, social analysis, and an environmental impact assessment of power plants fueled by oil palm plantation waste. The method used was the upscaling of a prototype of a 10 kW power plant to 100 kW. The results showed that it was technically and economically feasible to apply. The economic indicators were a positive NPV of USD 48.846 with an IRR of 9.72% and a B/C ratio of 1.16. The risk analysis predicted a probability of an NPV 49.94% above the base case. The study of the social aspects suggested that the construction of power plants has a positive impact in the form of increased community income and the growth of new economic sectors that utilize electricity as a primary source. An analysis of the environmental effects is critical so that the impacts can be minimized. Overall, the construction of small-scale power plants in oil palm plantations is worth considering as long as it is carried out following the applicable regulations. [ABSTRACT FROM AUTHOR]

A two echelon distribution system is often used to solve logistics problems. This study considers a two-echelon distribution system in reverse logistics context with the use of drop box facility as an intermediary facility. An optimization model of integer linear programming is proposed, representing a two-echelon vehicle routing problem with a drop box facility (2EVRP-DF). The aim is to find the minimum total costs consisting of vehicle transportation costs and the costs to compensate customers who have to travel to access these intermediary facilities. The results are then compared to those of common practice in reverse logistics. In common practice, customers are assumed to go directly to the depot to drop their goods. In addition, this study analyzes the environmental impact by adding a component of carbon emissions emitted by the vehicles. A set of comprehensive computational experiments is conducted. The results indicate that the 2EVRP-DF model can provide optimal costs and lower carbon emissions than the common practice. [ABSTRACT FROM AUTHOR]