Currently, most wastewater treatment plants do not meet the legal requirements, especially regarding phosphorus and nitrogen contents. In this work, real primary urban wastewater (P-UW) was used as culture medium for the growth of Chlorella vulgaris. Experiments were carried out in batch photobioreactors at laboratory scale. To determine the maximum nutrient removal levels and the optimal pH value for C. vulgaris growth, the following pH values were studied: 5, 6, 7, 8, 9, 10, and 11. Additionally, two control experiments were conducted using UW and tap water at the same conditions but without microalgae inoculation. The operational conditions were agitation rate = 200 rpm, T = 25 °C, aeration rate = 0.5 L/min, and continuous light with illumination intensity = 359 µE m−2 s−1. Significant higher growth was obtained at pH = 7. The direct use of C. vulgaris for P-UW treatment demonstrated high removal percentages of organic (COD and BOD5 removal = 63.4% and 92.3%, respectively) and inorg... [more]

Physico-chemical properties of microalgae biodiesel depend on the microalgae species and oil extraction method. Dioctyl phthalate (DOP) is a clear, colourless and viscous liquid as a plasticizer. It is used in the processing of polyvinyl chloride (PVC) resin and polymers. A new potential biofuel, hydrothermally liquefied microalgae bio-oil can contain nearly 11% (by mass) of DOP. This study investigated the feasibility of using up to 20% DOP blended in 80% diesel fuel (v/v) in an existing diesel engine, and assessed the performance and exhaust emissions. Despite reasonable differences in density, viscosity, surface tension, and boiling point, blends of DOP and diesel fuel were found to be entirely miscible and no separation was observed at any stage during prolonged miscibility tests. The engine test study found a slight decrease in peak cylinder pressure, brake, and indicated mean effective pressure, indicated power, brake power, and indicated and brake thermal efficiency with DOP ble... [more]

The current fossil fuel reserves are not sufficient to meet the increasing demand and very soon will become exhausted. Pollution, global warming, and inflated oil prices have led the quest for renewable energy sources. Algal biofuels represent a potential source of renewable energy. Algae, as the third generation feedstock, are suitable for biodiesel and bioethanol production due to their quick growth, excellent biomass yield, and high lipid and carbohydrate contents. With their huge potential, algae are expected to surpass the first and second generation feedstocks. Only a few thousand algal species have been investigated as possible biofuel sources, and none of them was ideal. This review summarizes the current status of algal biofuels, important steps of algal biofuel production, and the major commercial production challenges.

Waste rice straw biomass and its burning in open fields have become a serious issue of greenhouse gases emission and air pollution, which has a negative impact on public health and the environment. However, the environmental impact of burning this agro-waste can be mitigated by diverting it towards green biorefinery through the sustainable production of energy, biofuels, organic chemicals, and building blocks for various polymers. This will not only help to reduce the reliance on limited fuels and various chemicals derived from petroleum, but also help in the restoration of the environment in a sustainable manner through its complete utilization. To maximize the inherent conversion potential of rice straw biomass into valuable products, this agriculture waste biomass requires a comprehensive analysis and a techno-economic review for its sustainable management. This review article focuses on the sustainable management of rice straw waste biomass via innovative valorization approaches, a... [more]

The production of so-called advanced bioethanol offers several advantages compared to traditional bioethanol production processes in terms of sustainability criteria. This includes, for instance, the use of nonfood crops or residual biomass as raw material and a higher potential for reducing greenhouse gas emissions. The present review focuses on the recent progress related to the production of advanced bioethanol, (i) highlighting current results from using novel biomass sources such as the organic fraction of municipal solid waste and certain industrial residues (e.g., residues from the paper, food, and beverage industries); (ii) describing new developments in pretreatment technologies for the fractionation and conversion of lignocellulosic biomass, such as the bioextrusion process or the use of novel ionic liquids; (iii) listing the use of new enzyme catalysts and microbial strains during saccharification and fermentation processes. Furthermore, the most promising biorefinery approa... [more]

Availability of sustainable transportation fuels in future hinges on the use of lignocellulosic resources for production of biofuels. The process of biomass pyrolysis can be used to convert solid biomass resources into liquid fuels. In this study, laboratory experiments and process simulations were combined to gain insight into the technical performance of catalytic and thermal pyrolysis processes. Waste pinewood was used as a feedstock for the processes. The pyrolysis took place at 500 °C and employs three different catalysts, in the case of the catalytic processes. A process model was developed with Aspen Plus and a wide range of representative components of bio-oil were used to model the properties of the bio-oil blend. The results of the process model calculations show that catalytic pyrolysis process produces bio-oil of superior quality. Different technical process scenarios were explored based on the properties of the bio-oil after separation of water-soluble components, with the... [more]

Several Aspen Plus simulation files are presented which were used in the research paper by Chinedu Okoli and Thomas A. Adams II: "Design and Assessment of Advanced Thermochemical Plants for Second Generation Biobutanol Production Considering Mixed Alcohols Synthesis Kinetics" published in Industrial and Engineering Chemistry Research, vol 56, pp 1543-1558 (2017). Four Aspen Plus V8.4 workbook files are provided AS IS, with no guarantee of accuracy or functionality. They are the original files used in the underlying work and have not been groomed or sanitized.

The four base cases considered in this study are:

1. A "biomass only" process in which the entire plant's energy supply comes from biomass.
2. A "biomass only" process that uses a divided wall column as a part of the distillation sequence
3. A "NG and power import" process in which natural gas and grid electricity are used to provide supplementary power.
4. A "NG import" case in which natural gas (but not grid... [more]

Three Aspen Plus simulation files are presented which were used in the research paper by Chinedu Okoli, Thomas A. Adams II, Boris Brigljevic, and J.J. Liu: "Design and economic analysis of a macroalgae-to-butanol process via a thermochemical route" published in Energy Conversion and Management, vol 123, pp 410-122 (2016). Three Aspen Plus V8 workbook files are provided AS IS, with no guarantee of accuracy or functionality. They are the original files used in the underlying work and have not been groomed or sanitized.

The three files correspond to the three case studies in the paper:

1. A "biomass only" process in which the entire plant's energy supply comes from seaweed.
2. A "NG and power import" process in which natural gas and grid electricity are used to provide supplementary power.
3. A "NG import" case in which natural gas (but not grid electricity) is used to provide supplementary power.

It may be difficult to open the files in later versions of the software.... [more]

Compression ignition (CI) engines that run on high-viscosity fuels (HVF) like emulsified biofuels generally demonstrate poor engine performance. An engine with a consistently low performance, in the long run, will have a negative effect on its lifespan. Poor combustion in engines occurs mainly due to the production of less volatile, less flammable, denser, and heavier molecules of HVF during injection. This paper proposes a guide vane design (GVD) to be installed at the intake manifold, which is incorporated with a shallow depth re-entrance combustion chamber (SCC) piston. This minor modification will be advantageous in improving the evaporation, diffusion, and combustion processes in the engine to further enhance its performance. The CAD models of the GVD and SCC piston were designed using SolidWorks 2018 while the flow run analysis of the cold flow CI engine was conducted using ANSYS Fluent Version 15. In this study, five designs of the GVD with varying lengths of the vanes from 0.6D... [more]

Lecture slides from the Fall 2018 CHEM ENG 4A03/6A03 Energy System Engineering course at McMaster University are attached. Energy Systems Engineering is a survey course that discusses many ways in which energy products are produced, transported, converted, and consumed in our society today. The lectures correspond to two 50-minute lectures a week for 13 weeks (some slide decks take 2 or 3 lectures to complete). The course cannot cover all energy systems of course, but focus mostly on large-scale or common processes either in use today or currently in development and research. The course takes a chemical engineering perspective so more attention is paid to processes and thermochemical phenomena and less attention is paid to issues related to mechanical engineering or electrical engineering, although there is some intersection.

The lecture slides include the following topics:

1.1. Life Cycle Analysis (basic review)
1.2. Key Metrics in Energy Systems
2.1. Coal Production
2.2. Nat... [more]

The rapidly growing world population and rising consumption of biofuels are increasing demand for both food and biofuels. This exaggerates both food and fuel shortages. Using food crops such as corn grain to produce ethanol raises major nutritional and ethical concerns. Nearly 60% of humans in the world are currently malnourished, so the need for grains and other basic foods is critical. Growing crops for fuel squanders land, water and energy resources vital for the production of food for human consumption. Using corn for ethanol increases the price of U.S. beef, chicken, pork, eggs, breads, cereals, and milk more than 10% to 30%.

Crops for biofuels squanders cropland, water, and energy resources vital for food production needed for people.