Recent Patents on Engineering - Volume 9, Issue 2, 2015

Carbon dioxide (CO2) has been regarded as one of the most important greenhouse gases. Microalgae are considered as a potential solution for the decrease of atmospheric CO2 levels. The design of photobioreactors capable of capturing CO2 for bioconversion bioproducts is the main issue for techno-economic success in the field of phototrophic biotechnology. There are two kinds of large scale photobioreactors: open and closed system. The open systems are raceway ponds and closed systems are the flat plate, vertical tubular and horizontal tubular. These photobioreactors have their own advantages and disadvantages. Improvements in the design and configuration of photobioreactors are widely evaluated, with a focus on the utilization of physical parameter suitable for scaling. However, some considerations must be taken into account such as the height/diameter (H/D) ratio, an appropriate value, which maintains control from the structural and physicochemical point of view, helping to provide sufficient volume of microalgae culture, efficient transfer of mass, a reaction volume where light input to the system is adequate, good rate of culture mixture and better utilization of land space. This review seeks to show some photobioreactor designs, some patents and their scale-up to be implemented in the CO2 sequestration and biomass production.

Recent developments in three-dimensional (3D) printing technologies have revolutionized various branches of production and manufacturing. 3D printing goes hand-in-hand with cost effective manufacturing, high quality control because it implicates a manufacturing practice with low labor involvement and high precision manufacturing processes. A variety of 3D printing technologies are being introduced to serve the needs of a diverse population like in-house 3D printer for manufacturing of car accessories, 3D printing of human tissues and organs, 3D printing of micro batteries and many more. Moreover, clinics and hospitals are equipped with 3D printers that can 3D print our tooth filling, skin tissue or even a human organ. Repairing or servicing the components of a space shuttle or a space station in the outer space has been a major challenge, since 3D printing uses the process of additive manufacturing it can be a resourceful technology in solving the above challenges. With the major advancements in 3D printing, it is now possible to print micro batteries to power small incest drones and many such devices that are used in stealth operations. Hence, 3D printing can be said as the embodiment of modern manufacturing processes. In this paper, we review the recent technological advancements in materials and in technological aspects of 3D printing, identify future challenges and potential applications in engineering, manufacturing and tissue engineering. A brief discussion is provided on patents filed in different fields such a materials, their applications and industry-wise patent filing trends.

In the middle of 2013, the offshore installed wind capacity was 6.5 GW in European countries while by 2020 the total installed capacity is expected to reach 43 GW mainly by application of offshore wind turbines; the growth of offshore wind industry necessitates introducing concepts with potential of being classed without being much affected by different water depths. Initially, recent patents of offshore wind turbines are presented in this article. Afterwards, stochastic dynamic motion responses and generated power of a semisubmersible floating wind turbine for different water depths of 100 m and 200 m are examined for selected environmental conditions. The mooring line design is correspondingly modified to provide proper station keeping as well as appropriate interactive influence on the dynamic responses of the semisubmersible wind turbine without affecting the generated power. Fully coupled aero-hydro-servo-elastic numerical models have been developed and integrated time-domain approach has been applied in order to investigate the dynamics of the semisubmersible floating wind turbine. The motion responses, mooring lines effective tension as well as wind turbine performance are compared for different water depths and environmental conditions. Hence, the present semisubmersible floating wind turbine can be classified which means an optimized design can easily be modified for new offshore site with different water depth without the need of major modifications.

This article reviews recent patents pertaining to the technological achievements and shortcomings of anaerobic digestion technology that optimize biogas production for use in fuel cells. The technical field of anaerobic digestion is well understood and known as an effective means to safely process organic waste and produce useful byproducts including compost, methane and hydrogen gas. While fuel cells have proven effective in producing power from biogas, including methanol and hydrogen derived thereof, the process of doing so with anaerobic digester gas (ADG) remains costly and more complex compared to sourcing fuel from natural gas or pure methanol. This paper reviews recent advancements in anaerobic digestion technology that optimize gas production for use in fuel cells, including improved anaerobic digestion processes, establishing more efficient digester designs, lowering operational costs, and purifying biogas to better suit fuel cells. A few developing niche applications are also discussed. A patent search revealed only 59 US patents that focus specifically on the use of anaerobic digestion to power fuel cells, 32% of which were published in the last five years. Similarly, 77 US patent application publications were found using the same search with 70% of those published in the last five years. It appears that while advancements are being made, growth of the technology is slow and widespread use of fuel cells remains more of a goal than a current reality. While much advancement is based upon improvements of older anaerobic digester technology, some patent applications are directed to lesser-known arts such as microbial fuel cells.

Our current economic and industrial growth relies on fossil fuels that can be easily and economically converted into energy and useful chemicals, but this economic model is endangered by the depletion of these resources and by environmental problems as the emission of CO2 and other greenhouse gases. To solve this dilemma, we can find inspiration in natural photosynthetic organisms that consider CO2 as a carbon source and not as a waste, and power its transformation into valuable chemicals with renewable solar energy. To transform this vision into a practical and affordable reality, several challenging scientific and technical questions must be solved, including: the cost effective production of stable photocatalysts, the elucidation of the mechanisms of formation of useful compounds from CO2, or the implementation of the technology using scalable reactor concepts. This article presents a review of recent developments and patents related to “artificial photosynthesis” systems, covering key aspects such as the transition from macro-sized photo-electrochemical cells to nanostructured catalyst, the combination of these catalysts with organic or inorganic light sensitizers in order to extend the light wavelength range in which they are active, and the design of artificial photosynthesis reactors.

Many aero-engine blades are long-term operated in harsh environments. Due to high temperature and pressure in operation, as well as many external impacts, blades may have various defects, such as erosion, distortion, wear, cracks and impact dents. In terms of prolonging the service lives of blades, repair is an inevitable choice since replacement is far more expensive. Along with the development of the advanced manufacturing technology (AMT), repairing technologies of blades, which have always mainly depended on the manual operation in the past several ten years, have been one hot research pot in the aircraft maintenance. The research emphasis is to improve the automation level of repairing process. The reconstruction of digital model of damaged blade, overlay welding and machining the welded excess are the three key technologies which influence the automation level of repairing. In this paper, the approaches, methods and methodologies used for the three technologies are reviewed as well as the comparisons between them are made. Meanwhile, the research directions are pointed out. The future research works should be emphasized on reconstructing the damaged tip independent of design model or unused blade, repairing the single-crystal blade with laser, repairing the blisk and improving the robot repairing system. Here, We also discussed few related patents.

Based on cold experiment device of biomass internal circulation fluidized bed, different sizes of silica sand and bed material heights experiments were done under normal temperature and pressure respectively, influences of particle sizes and heights of the bed material on minimum fluidization velocity were analyzed from the relationship diagram between differential pressure and air velocity. The results show that minimum fluidization velocity increases as particle diameters increases; and it is independent from bed material height. A thorough literature survey on the calculation correlations of minimum fluidization velocity was conducted, which revealed that the relative errors between values predicted by the calculation correlations and the experimental values were huge. The calculation method of minimum fluidization velocity was given based on modified Ergun equation and minimum fluidization voidage estimation calculation, the predicted values of the method are in good agreement with the experimental values, the relative error is less than 10%, and it provides a reliable reference basis for internal circulation fluidized bed structure optimization, amplification design and operation. Here, we also discussed few related patents.