Projects | Maghimai Marcus

Agri Food Production

Wed, 27 Apr 2016 00:00:00 +0000

System explanation

The system boundary of crop production includes two main components: farm inputs and farm fuel use. Farm inputs include the application of seed, fertilizers, liming materials, and pesticides. Farm fuel use includes the energy required for farm machinery operations, farm transport, machinery supply (indirect energy), and heating and lighting requirements during drying and storage.

Farm field operations include general activities such as seeding, weed control, applying soil amendments, and harvesting. Seeding and tillage of annual crops include activities such as plow, disk and seed; weed control and pesticides application include cultivation and spraying; applying soil amendments includes use of fertilizers and lime; and harvest of annual crops include swathing (cut and windrow), combining and carting the grains off the field. Fuels used in farm machinery such as seeders, cutter bars, conveyor belts, grinders, crushers, shakers, harvesters, rollers, and tractors are also considered.

Building Materials

Wed, 27 Apr 2016 00:00:00 +0000

Schematic representation of cement production

Cement Production

Schematic representation of float glass production

Float Glass Production

Schematic representation of polyurethane production

Polyurethane Production

Schematic representation of steel mfa

Material Flow of Steel

Microbial Electrosynthesis

Wed, 27 Apr 2016 00:00:00 +0000

Technology description

The microbial electrosynthesis system performs both oxidation and reduction of organic and inorganic substrates using electrotrophs such as Geobacteraceae species and Shawanaellasea species. These bacterial spp. have c-type cytochromes present in their outer cell membranes and pili to faciliate direct electron transfer (DET) which sustains the process (Martinez et al.2013; Rabaey &Rozendal, 2010). Those bacterial species are generally immobilised on the surfaces of anode and cathode in an anaerobic environment. The electrodes are connected through a power source and separated by a selective membrane. The general mechanism inside the cell involves oxidation of electron donor substrate by the microbes resulting in electrons being released to anode, which is then mobilised towards cathode via the power source. At cathode, along with generated protons permeated across membrane, the electron flow is received by microbes to reduce the electron accepting substrates, which will result in fuels, chemicals and less toxic substances (Nevin et al., 2010). The flow of electric current between anode and cathode sustains the electrode catalysis of microbes mostly with little electrical input and zero chemicals, while the release of CO₂ at anode could be collected and reused and reduced at cathode to produce valuable byproducts such as biopolymers, methane, and ethanol, etc., which in turn makes the system more attractive for waste management and bioremediation. The selective membranes prevents the flow of oxygen to cathode region, which ensures the accumulation of proton charge. Further, poising the cathodes at selective electric potential (Nernst law) prevents the build up of explosive gases inside the chamber that ensures better control over the system (Lovley, 2011).

Scope and system boundary

As in figure 1, the system boundary includes the inputs required for production of biogas and ethanol such as energy (electricity mix data, pretreatment and post-treatment, and manufacture of chemicals), fuel (transportation), chemicals, electrodes, reactors, and infrastructure of WWTP. Negligible emissions such as EOL of infrastructure can be avoided. Comparison studies (Foley et al.2010) premise their findings based on assumption that all the systems treat equal amount of input (waste water) with selective current density (1000 A.m3). When integration happens, the MEC system has to be modelled for reduction in inputs received and the change in respective current density (applied voltage) at which it operates.

Allocation

Waste effluents from the system generate by-products such as biogas, ethanol, and CO₂. Biogas remains an alternative to natural gas; ethanol has multiple uses with production from chemical and fermentation methods; and CO₂ has wide applications in industry and it can also used as an input to same MES system or another MES system to produce other valuable by-products . Therefore, system could be expanded to credit the avoided production of natural gas , ethanol and CO₂ by conventional production methods. If the resultant sludge from MES is used for fertiliser rather than being landfilled, then the system may be expanded further. However, it is expected that savings from expansion would be nullified by transportation and storage of fertiliser, given the quantity of fertiliser obtained. Therefore , it might be modelled for being landfilled or being left out based on cut-off approach if the impact is negligible.

References

Foley, J.M., Rozendal, R.A., Hertle, C.K., Lant, P.A., & Rabaey, K.(2010). Life Cycle Assessment of High-Rare Anaerobic Treatment, Microbial Fuel Cells, and Microbial Electrolysis Cells. Environmental Science and Technology 44(9):3629-37.

Lovley, D.R.(2011). Powering microbes with electricity:direct electron transfer from electrodes to microbes. Environmental Microbiology Reports. 3(1):27-35.

Martinez, A.C., M ́elanie Pierra, Eric Trablyand , Nicolas Bernet. High current density via direct electron transfer by the halophilic anode respiring bacterium Geoalkalibacter subterraneus. Physical Chemistry Chemical Physics, Royal Society of Chemistry, 2013, 15 (45), pp.19699 - 19707.

Nevin, K.P., Woodard,T.L., Franks, A.E., Summers, Z. M. and Lovley, D.R. (2010). Microbial electrosynthesis: feeding microbes electricity to convert carbon dioxide and water to multicarbon extracellular organic compounds. mBio 1(2):e00103-10. doi:10.1128/mBio.00103-10.

Rabaey, K., and Rozendal, R.A.(2010). Microbial electrosynthesis: revisiting the electrical route for microbial production. Nature Reviews Microbiology, 8:706-716.

Petroleum Refinery

Wed, 27 Apr 2016 00:00:00 +0000

Scope and System

It is a well to refinery gates study. The functional unit is 1 MJ of the output fuel. It follows an aggregated approach in which the refinery plant is considered to be a single module which encompasses sub-modules. The sub-process emissions in refinery are aggregated and emissions are calculated for total energy use. The refinery configurations are broadly classified as heavy crude refineries, medium crude, and light crude. Based on the above configurations, LCI is intended for the following refinery outputs: LPG, gasoline (petrol), naphtha, kerosene, jet-fuel, diesel, heavy fuel oil, lubricating oil, wax, asphalts, and liquid fuel from coal.

The whole framework could be divided into two types of models for the ease of data collection: foreground model and background model. Foreground model is developed on primary data while the background model is based on secondary data. In this study, extraction, transportation, infrastructure, blending components (chemicals) and electricity will be part of the background model. Refinery and its sub-processes are covered under foreground model. However, for some components of foreground model such as import from foreign countries that involves global supply chain, resorting to background model is imminent due to complex supply chains involved.

The study targets eight categories of refined fuels: 1) butane and propane, 2) naphtha, 3) gasoline(petrol), 4) kerosene and jet fuel, 5) diesel and gas oil, 6) lubricants and other products, 7) fuel oils and 8) other residues.The technologies that are assumed for the refinery process flows are :

Unifer for sulphur and nitrogen removal for gasoline.
Merox for desulphurzation in jet fuel and kerosene.
Hydrotreaters for diesel and gas oil.
Vacuum distillation units for fuel oils
Catalytic Cracking unit is used to treat lighter fuels from the vacuum distillation.
Heavier Fuels from the vacuum distillations unit are processed through visbreaker units