scholarly journals Bioreactor Operating Strategies for Improved Polyhydroxyalkanoate (PHA) Productivity

Polymers ◽  
2018 ◽  
Vol 10 (11) ◽  
pp. 1197 ◽  
Author(s):  
Warren Blunt ◽  
David Levin ◽  
Nazim Cicek
Keyword(s):  
Production Costs ◽  
Scale Production ◽  
Fed Batch ◽  
Continuous Bioreactor ◽  
Carbon Substrates ◽  
Pure Cultures ◽  
High Production ◽  
Operating Strategies ◽  
Major Factors ◽  
Industrial Scale Production

Microbial polyhydroxyalkanoates (PHAs) are promising biodegradable polymers that may alleviate some of the environmental burden of petroleum-derived polymers. The requirements for carbon substrates and energy for bioreactor operations are major factors contributing to the high production costs and environmental impact of PHAs. Improving the process productivity is an important aspect of cost reduction, which has been attempted using a variety of fed-batch, continuous, and semi-continuous bioreactor systems, with variable results. The purpose of this review is to summarize the bioreactor operations targeting high PHA productivity using pure cultures. The highest volumetric PHA productivity was reported more than 20 years ago for poly(3-hydroxybutryate) (PHB) production from sucrose (5.1 g L−1 h−1). In the time since, similar results have not been achieved on a scale of more than 100 L. More recently, a number fed-batch and semi-continuous (cyclic) bioreactor operation strategies have reported reasonably high productivities (1 g L−1 h−1 to 2 g L−1 h−1) under more realistic conditions for pilot or industrial-scale production, including the utilization of lower-cost waste carbon substrates and atmospheric air as the aeration medium, as well as cultivation under non-sterile conditions. Little development has occurred in the area of fully continuously fed bioreactor systems over the last eight years.

Preliminary Cost Estimates for Massive Hydrogen Production Using SI Process

2008 ◽  
Author(s):  
K. J. Yang ◽  
K. Y. Lee ◽  
T. H. Lee
Keyword(s):  
Hydrogen Production ◽  
Large Scale ◽  
Fossil Fuels ◽  
Production Costs ◽  
Scale Production ◽  
Cost Estimates ◽  
Production Of Hydrogen ◽  
Major Factors ◽  
The Cost ◽  
Hydrogen Systems

As a preliminary study of cost estimates for nuclear hydrogen systems, the hydrogen production costs of the nuclear energy sources benchmarking GT-MHR and PBMR are estimated in the necessary input data on a Korean specific basis. G4-ECONS was appropriately modified to calculate the cost for hydrogen production of SI process with VHTR as a thermal energy source rather than the LUEC. The estimated costs presented in this paper show that hydrogen production by the VHTR could be competitive with current techniques of hydrogen production from fossil fuels if CO2 capture and sequestration is required. Nuclear production of hydrogen would allow large-scale production of hydrogen at economic prices while avoiding the release of CO2. Nuclear production of hydrogen could thus become the enabling technology for the hydrogen economy. The major factors that would affect the cost of hydrogen were also discussed.

scholarly journals Techno-Economic Analysis on an Industrial-Scale Production System of Polyhydroxyalkanoates (PHA) from Cheese By-Products by Halophiles

Processes ◽  
2021 ◽  
Vol 10 (1) ◽  
pp. 17
Author(s):  
Ke Wang ◽  
Alex Michael Hobby ◽  
Yike Chen ◽  
Allan Chio ◽  
Bryan Martin Jenkins ◽  
...  
Keyword(s):  
Production System ◽  
Unit Price ◽  
Process Efficiency ◽  
Industrial Scale ◽  
Scale Production ◽  
Haloferax Mediterranei ◽  
Simulated System ◽  
Major Factors ◽  
By Products ◽  
Industrial Scale Production

Polyhydroxyalkanoates (PHA) are a family of biodegradable plastics used as an ecofriendly alternative for conventional plastics in various applications. In this study, an industrial-scale PHA production system was designed and analyzed for the material flows and economics with the use of SuperPro Designer. Haloferax mediterranei was utilized to produce poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV). Byproduct streams from a local cheese plant, with an input of 168.7 metric ton/day (MT/day) lactose, were used as the feedstock. Three scenarios with different processes for the treatments of used enzyme and spent medium were investigated and the major factors that influence the overall economics were identified. The simulated system produces 9700 MT/year PHBV with a yield of 0.2 g PHBV/g lactose and an overall process efficiency of 87%. The breakeven price was found to be more sensitive to the lactose price than enzyme price. The scenario with enzyme reuse and spent medium recycling achieved the lowest breakeven price among others, which can be less than 4 $/kg PHA based on the delactosed permeate (DLP) unit price. The study suggests utilizing dairy derived feedstocks has the potential to make PHA competitive in the bioplastic market, which could be beneficial to both dairy and bioplastic industries.

AN ECONOMICAL STUDY TO MEASUREMENT OF MARKETING EFFICIENCY IN CALF FATTENING FIELDS IN NINEVEH GOVERNORATE(2018)

2020 ◽  
Vol 51 (4) ◽  
Author(s):  
Abdullah & Al-Taye
Keyword(s):  
Commodity Prices ◽  
Red Meat ◽  
Production Costs ◽  
Meat Production ◽  
Marketing Efficiency ◽  
Basic Source ◽  
Essential Nutrient ◽  
High Production ◽  
Marketing Costs ◽  
Marketing Margins

This study was aimed at assessing marketing efficiency in the main sites of meat production of calf fattening fields in the private sector due to the importance of meat, especially red meat, which has essential nutrient for human body growth and high commodity prices depending on the measurement indicators used to suit the nature of the research conducted in calves fattening production fields in Gogjali region- Nineveh  (2018). The basic source data of the study is obtained from sources on the ongoing ground- marketing questionnaire of three levels, the producer, the wholesaler, the retailer and two fields groups of caste random sample. The first group included (100) fields with imported calves class. The second included (51) fields with local calves class. Whereas, according to the production and marketing costs indicator, the average of marketing efficiency (ME1 ) of marketed meat in both groups of claves fattening fields amounted (92.47, 93.39%) respectively for a kilogram which is a sign of high production costs and, according to the marketing margins indicator, the average of marketing efficiency (ME2 ) of marketed meat in both groups of claves fattening fields amounted (86.89,79.13 %) for per kg which is a sign of high marketing margins. Thus the study concluded a high value of marketing efficiency using the first scale with the fattening period time for both groups while marketing efficiency by using the second scale was characterized by the gradual decline in the imported fattening fields and a gradual rise in the local fattening fields.  The study recommends supporting production inputs (fodder, treatment), unifying markets and limiting the    importation of red meat importation  in order to obtain a good production and currency policy by which the production costs could be reduced to the minimum .

scholarly journals Economic and Sustainability of Biodiesel Production—A Systematic Literature Review

2021 ◽  
Vol 3 (1) ◽  
pp. 19-36
Author(s):  
Tamás Mizik ◽  
Gábor Gyarmati
Keyword(s):  
Literature Review ◽  
Systematic Literature Review ◽  
Volatile Fatty Acids ◽  
First Generation ◽  
Production Costs ◽  
Raw Material ◽  
Biodiesel Production ◽  
Important Research Topic ◽  
The Social ◽  
High Production

As Earth’s fossil energy resources are limited, there is a growing need for renewable resources such as biodiesel. That is the reason why the social, economic and environmental impacts of biofuels became an important research topic in the last decade. Depleted stocks of crude oil and the significant level of environmental pollution encourage researchers and professionals to seek and find solutions. The study aims to analyze the economic and sustainability issues of biodiesel production by a systematic literature review. During this process, 53 relevant studies were analyzed out of 13,069 identified articles. Every study agrees that there are several concerns about the first-generation technology; however, further generations cannot be price-competitive at this moment due to the immature technology and high production costs. However, there are promising alternatives, such as wastewater-based microalgae with up to 70% oil content, fat, oils and grease (FOG), when production cost is below 799 USD/gallon, and municipal solid waste-volatile fatty acids technology, where the raw material is free. Proper management of the co-products (mainly glycerol) is essential, especially at the currently low petroleum prices (0.29 USD/L), which can only be handled by the biorefineries. Sustainability is sometimes translated as cost efficiency, but the complex interpretation is becoming more common. Common elements of sustainability are environmental and social, as well as economic, issues.

scholarly journals Progress in Research on Carbon Nanotubes Reinforced Cementitious Composites

2015 ◽  
Vol 2015 ◽  
pp. 1-16 ◽  
Author(s):  
Qinghua Li ◽  
Jintao Liu ◽  
Shilang Xu
Keyword(s):  
Carbon Nanotubes ◽  
Large Scale ◽  
High Strength ◽  
Cementitious Composites ◽  
Scale Production ◽  
Multiwalled Carbon ◽  
Factors Affecting ◽  
Environment And Health ◽  
Research Activities ◽  
Major Factors

As one-dimensional (1D) nanofiber, carbon nanotubes (CNTs) have been widely used to improve the performance of nanocomposites due to their high strength, small dimensions, and remarkable physical properties. Progress in the field of CNTs presents a potential opportunity to enhance cementitious composites at the nanoscale. In this review, current research activities and key advances on multiwalled carbon nanotubes (MWCNTs) reinforced cementitious composites are summarized, including the effect of MWCNTs on modulus of elasticity, porosity, fracture, and mechanical and microstructure properties of cement-based composites. The issues about the improvement mechanisms, MWCNTs dispersion methods, and the major factors affecting the mechanical properties of composites are discussed. In addition, large-scale production methods of MWCNTs and the effects of CNTs on environment and health are also summarized.

Semi-industrial Scale Production of a New Yeast with Probiotic Traits, Cryptococcus sp. YMHS, Isolated from the Red Sea

2017 ◽  
Vol 10 (1) ◽  
pp. 77-88 ◽  
Author(s):  
Ashraf F. El-Baz ◽  
Hesham A. El-Enshasy ◽  
Yousseria M. Shetaia ◽  
Hoda Mahrous ◽  
Nor Zalina Othman ◽  
...  
Keyword(s):  
Red Sea ◽  
Industrial Scale ◽  
Scale Production ◽  
New Yeast ◽  
Industrial Scale Production

Isolasi dan Potensi Enzim Hidrolase Bakteri Simbion Padina sp. dari Pantai Lengkuas Belitung

2021 ◽  
Vol 23 (1) ◽  
pp. 11-17
Author(s):  
Siti Nur Jannah ◽  
Yumna Rahmadias Hanifa ◽  
Adi Budi Utomo ◽  
Ashar Kurnia Dian Prambodo ◽  
Arina Tri Lunggani
Keyword(s):  
Marine Organism ◽  
Marine Ecosystem ◽  
Gram Negative Bacteria ◽  
Scale Production ◽  
Market Demand ◽  
Bacterial Isolates ◽  
Clear Zone ◽  
Plate Method ◽  
Sea Use ◽  
Industrial Scale Production

Marine organism is one of the riches in the ocean of Indonesia. The benefits of sea use for new products produced are widely used and have high market demand. Enzymes that have marine interests have unique properties and have good benefits for industry. This study aims to isolate the bacteria that have symbionts with Padina sp and determine the potential of the enzyme hydrolase produced by these bacteria. Isolation is done by the spread plate method. Pure isolates obtained were then tested for the potential of the enzyme hydrolase on selective media. Clear zone measurements are performed to determine which bacterial isolates are good for enzyme production. The results obtained by 6 isolates of pure bacteria, all of which include Gram negative bacteria that form bacilli. All isolates had the ability to produce different Protease, Lipase, Amylase and Cellulase enzymes. The enzymes obtained from these symbiotic bacteria are expected to be used for industrial-scale production in Indonesia. In addition, the presence of this symbiont bacteria is able to reduce the level of exploitation of Padina sp and contribute to preserving the marine ecosystem.

Study on the Preparation and Amplification Experiment of Al-Pillared Montmorillonite

2011 ◽  
Vol 396-398 ◽  
pp. 1440-1445
Author(s):  
Gang Chen ◽  
Chun Jie Yan ◽  
Jin Feng Shou ◽  
Juan Mei ◽  
Nan Nan Chen
Keyword(s):  
Pilot Scale ◽  
Micropore Volume ◽  
Bet Surface Area ◽  
Scale Production ◽  
Mass Ratio ◽  
Optimum Conditions ◽  
Technical Parameters ◽  
Pillared Montmorillonite ◽  
Commercial Aluminium ◽  
Major Factors

A method of preparation and pilot scale production of Al-pillared montmorillonite has been developed. There is a minimum of time and amount of liquid. And it is simpler to operate than the conventional method of pillaring by using the commercial aluminium hydroxychloride(PAC) powder as the pillaring agent. Here, the effect of the major factors such as the mass ratio of PAC to montmorillonite, the concentration of montmorillonite slurry, the sodium agent pretreatment, washing times and drying temperature on the Al-pillared montmorillonite are studied. Then the optimal technical parameters is determined. XRD, BET surface area and micropore volume are applied in order to study the structure and properties of Al-pillared montmorillonite. As a result, the amplification experiment under the optimum conditions shows that this method offers the potential for extension to an industrial-scale process.

Industrial Scale Production of L-B Layers

1989 ◽  
pp. 41-49 ◽  
Author(s):  
O. Albrecht ◽  
T. Ginnai ◽  
A. Harrington ◽  
D. Marr-Leisy ◽  
V. Rodov
Keyword(s):  
Industrial Scale ◽  
Scale Production ◽  
Industrial Scale Production

scholarly journals USE OF ZEOLITE IS ACTIVATED AS SUBSTITUTION OF CEMENT FOR PRICE AND COST

2018 ◽  
Vol 1 (1) ◽  
Author(s):  
Ahmad Nurfiki Alwi ◽  
Arif Rahman Setiaji ◽  
Abdurrohim Kurnia Agung ◽  
Abdul Halim
Keyword(s):  
Compressive Strength ◽  
Fly Ash ◽  
Hypothesis Testing ◽  
Building Materials ◽  
Production Costs ◽  
Light Weight ◽  
Residential Community ◽  
High Production ◽  
The Cost ◽  
Cement Compounds

The number of economic needs is one of the fundamental aspects to support the survival of every individual in an area.  If seen in general, the cost of building the building and residential community still use building materials and installation costs are relatively higher.  With the advancement of technology has found a lightweight brick that has better strength, lighter, faster installation and environmentally friendly, so many people began to switch to using lightweight bricks.  For now the price of lightweight brick is still expensive, but this deficiency is covered with the speed of mounting and light weight so overall lightweight brick usage on certain patterns is very profitable.  The use of cement on lightweight bricks leads to high production costs.  With the above problems we have a breakthrough to replace the cement by using zeozolites containing silica compounds that resemble one of the cement compounds.  In this research, cement replacement with Zeolite is 20%, 40% and 60%.  Before use Zeolite was first activated using Fly Ash ratio of 65% Zeolite: 35% Fly Ash and 50% Zeolite: 50% Fly Ash, also activated using Ca (OH) 2 ratio 65% Zeolite: 35% Ca (OH) 2  And 50% Zeolite: 50% Ca (OH) 2.  Thus, there are 15 compositions including the control composition, each composition will be made up of 10 specimens.  Hypothesis testing using two way anova, tested is the effect of cement change treatment with Zeolite and comparison of Zeolite composition with Fly Ash and Ca (OH) 2 to compressive strength, absorption and cost. Keywords: Zeolite, Cement, compressive strength, Cost

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