Microalgae Oil: Algae Cultivation and Harvest, Algae Residue Torrefaction and Diesel Engine Emissions Tests

This study elucidates the characteristics of persistent organic pollutants (POPs), including polychlorinated dibenzo-pdioxins and dibenzofurans (PCDD/Fs), polychlorinated biphenyl (PCBs), polybrominated dibenzo-p-dioxins and polybrominated dibenzofurans (PBDD/Fs) and polybrominated diphenyl ethers (PBDEs), that are emitted from a generator (non-road diesel engine) that is fueled with a blend of waste cooking oil biodiesels (WCO-biodiesels). Experimental results reveal that the mass concentrations of PCDD/Fs, PCBs, PBDD/Fs and PBDEs from the diesel generator that is fueled with petroleum diesel (D100) under loads of 1.5 kW and 3.0 kW were 583-875 pg , respectively. W20 and W40 emitted 15-65% and 23-85% less of these POPs by mass (and 25-47% and 46-91% by toxicity), respectively. Among the tested fuel blends, the W40 exhibited the greatest emission factor reductions of mass and toxicity of these four POPs, despite of the load. Therefore, WCO-biodiesels can feasibly be used as an alternative generator fuel, favoring the recycling/reuse of waste oils and mitigating hazards to human health and environment.

Section: Introductionmentioning

confidence: 99%

Characteristics of Persistent Organic Pollutant Emissions from a Diesel-Engine Generator Fueled Using Blends of Waste Cooking Oil-Based Biodiesel and Fossil Diesel

Tsai

Chen

Huang

et al. 2016

“…The major sources of PAHs are heating (coal, oil, gas and wood), petroleum refinery, coke production, fossil fuel combustion, industrial processes, steel and iron furnaces, incinerators, and vehicles (Chen et al, 2014;Li et al, 2014b;Huang et al, 2015;Mwangi et al, 2015a;b;Qin et al, 2015). Since several PAHs have been classified as human carcinogens (groups 2B, 2A and 1) by the International Agency for Research on Cancer (IARC, 1987;Kamal et al, 2016), public concern with the release of these carcinogenic pollutants in the global environment has recently increased.…”

Section: Introductionmentioning

confidence: 99%

Distribution and Sources of Atmospheric Polycyclic Aromatic Hydrocarbons at an Industrial Region in Kaohsiung, Taiwan

Lai

Tsai

Chen

et al. 2017

The chemical mass balance model was applied to estimate the major sources of atmospheric polycyclic aromatic hydrocarbons (PAHs) at an Industrial Region in Kaohsiung, Taiwan. The gaseous and particulate phases of 16 individual compounds were analyzed between March 2012 and August 2012. The mean total concentrations and total BaP eq were higher during the cold season and lower during the warm summer, with gaseous PAHs predominant at all sites. Low weight-PAHs and median weight-PAHs were found predominantly in the gaseous phase, while high weight-PAHs were predominant in the particle phase. Results from the receptor model revealed that the average contributions were 38.2%, 27.2%, 20.7%, 6.8%, 5.2%, and 2.0% from vehicles, heavy oil combustion, natural gas combustion, incinerator, tetrabromobisphenol A production, and diesel combustion at the seven receptors, respectively. Vehicle emissions appear to be the significant source of PAHs in the investigated area, although other industrial sources, as described above, also have an impact on the total PAHs.

“…For instance, microalgal cells are sunlight-driven cell factories that can convert CO 2 into raw materials for producing biofuels (Mwangi et al, 2015), animal food chemical feedstocks, and high-value bioactive compounds (e.g., docosahexaenoic acid). It can be achieved by two separate reactions: lightdependent and light-independent sets.…”

Section: Conversionmentioning

confidence: 99%

Challenges and Perspectives on Carbon Fixation and Utilization Technologies: An Overview

Ping

Pan

Pei

et al. 2016

This paper provides an overview of state-of-the-art carbon fixation and utilization technologies. Several carbon capture processes, such as chemical absorption and chemical looping, are reviewed and illustrated. In addition, various types of chemicals and fuels that can be produced using concentrated CO 2 (or other forms) through physical, chemical, or enhanced biological methods are presented. Among those carbon conversion methods, two promising approaches, i.e., microalgae ponds and accelerated carbonation using alkaline solid wastes, are reviewed in detail. Microalgae are fast-growing and ubiquitous photosynthetic organisms, which are rich in protein and can be converted to biodiesel fuel. They have been recognized as an alternative feedstock not only because they use CO 2 from the atmosphere but also due to their high lipid content per biomass compared to other plants. In this study, for the microalgae technologies, the principles and applications of open pond systems are discussed in terms of both technological and economic considerations. The important operation parameters affecting productivity of microalgae, including light intensity, temperature, mixing, CO 2 delivery, accumulation of dissolved oxygen, and salinity are summarized. On the other hand, accelerated carbonation technologies are an attractive and feasible approach to integrating alkaline solid waste treatment with CO 2 fixation and utilization. In this study, the performance of various carbonation processes is critically reviewed from the perspectives of process design, energy consumption, and environmental benefits. The carbonated solid product can also be used as supplementary cementitious materials in a blended cement or concrete block. Accordingly, the performance of cement pastes with carbonated product, in terms of workability and strength development, are evaluated from the cement chemistry point of view. Cement manufacturing is an energy and material intensive process, with high annual production. It is noted that, through the accelerated carbonation process, significant indirect environmental benefits can be realized.