[4-1600-D] Other Categories (1)

[4-1600-D-05] Sensitivity and Dynamic Analysis of Microalgae Fuel Production System Using LCA

*Riaru ISHIZAKI¹, Ryozo Noguchi², Agusta Samodra Putra¹, Tofael Ahamed², Makoto M. Watanabe³ (1. Graduate School of Life and Environmental Sciences, University of Tsukuba(Japan), 2. Faculty of Life and Environmental Sciences, University of Tsukuba(Japan), 3. Algae Biomass and Energy System R&D Center, University of Tsukuba(Japan))

Keywords:Bio-production systems engineering, Microalgae, Concurrent engineering, Visualization, Standardization

The purpose of this research is to develop a data analysis system for microalgae that included upstream to downstream processes of production. Energy profit ratio (EPR) and life cycle assessment (LCA) were applied for evaluating production capability refer to output, quality besides output performances, cost, and delivery (QCD). A system approach is required to develop a data analytical platform to increase QCD performances at the different stages of microalgae production based on the concept of concurrent engineering. The forecasting of dynamic result changes could play a key role to data shearing at the different sub-unit of microalgae production system. The microalgae oil-production processes consisted of four sub-unit: open raceway pond (ORP), flocculation, drum filtration, and hydrothermal liquefaction (HTL). The system was based on the experimental data from the Minami-Soma pilot project. Three scenarios were established. Scenario 1 was built a new bioplant on an industrial site to produce a 17.48 kg/day bioclude, by processes algae-containing liquid (50 t/day) from a 0.1 ha ORP. Scenario 2 was built with the thermal power plant site and added the use of heat from there, and the wastewater to scenario 1. In scenario 3, the depth of the water changed from 0.2 to 0.4 meter and related equipment was scaled up to follow scenario 2. The calculated EPR was observed 0.57, 10.81, 10.41 for scenario 1, 2, 3, respectively. The primary contributor was discharged heat from the power plant for utilizing in the HTL process, and replacement of the wastewater treatment energy by microalgae. The EPR was considered from running energy that did not include the energy from the initial investment and input material production. The global warming potential with accumulated value for 100 years (GWP 100) was reported as 47.5, 53.4, 25.4 kg CO₂eq in CO₂ conversion per kg of biocrude for scenario 1, 2, 3, respectively. The acidification potential (AP) and eutrophication potential (EP) had similar trends. In scenario 2, the environmental impact was not changed compared to scenario 1. In this regard, construction of the wastewater treatment plant was added in the system boundaries. In addition, the depth of the ORP at the scenario 3 was doubled. Therefore, the environmental impact per product was observed half compare to scenario 2. The major cost of production was labor and depreciation costs of the HTL plants. Through the LCA-based system approach, microalgal production could be suggested for the best optimal production pattern in any site-specific requirement of environment for sustainability.