ABSTRACT
Water is a precious resource for agriculture and most of the land is irrigated by tube wells. Diesel engines and electricity-operated pumps are widely used to fulfill irrigation water requirements; such conventional systems are inefficient and costly. With rising concerns about global warming, it is important to choose renewable energy source. In this study, SPVWPS has been optimally designed considering the water requirement, solar resources, tilt angle and orientation, losses in both systems and performance ratio. A PVSyst and SoSiT simulation tools were used to perform simulation analysis of the designed solar photovoltaic WPS. After designing and performance analysis, farmers were interviewed during fieldwork to assess socioeconomic impacts. In the result section, performance of PV system is analyzed at various tilt angles and it is established that system installed at a 15° tilt angle is more efficient. The annual PV array virtual energy at MPP of designed photovoltaic system is 33342 kWh and the annual energy available to operate the WPS is 23502 kWh. Module array mismatch and ohmic wiring losses are 374.16 kWh and 298.83 kWh, respectively. The total annual water demand of the selected site is 80769 m³ and designed SPWPS pumped 75054 m³ of water, supplying 92.93% of the irrigation demand. The normalized values of the effective energy, system losses, collection losses and unused energy in the SPVWP system are 2.6 kW/kWp/day, 0.69 kW/kWp/day, 0.72 kW/kWp/day and 0.48 kW/kWp/day, respectively. The annual average performance ratio of the proposed system is 74.62%. The results of the interviews showed that 70% of farmers are extremely satisfied with the performance of SPVWPS and 84% of farmers indicated that they did not incur any operating costs. The unit cost of the SPWPS is 0.17 /kWh, which is 56.41% and 19.04% less expensive than the cost of diesel and grid electricity.
ABSTRACT
Over the last several years, the number of concepts and technologies enabling the production of environmentally friendly products (including materials, consumables, and services) has expanded. One of these ways is cradle-to-cradle (C2C) certifiedTM. Life cycle assessment (LCA) technique is used to highlight the advantages of C2C and recycling as a method for reducing plastic pollution and fossil depletion by indicating the research limitations and gaps from an environmental perspective. Also, it estimates the resources requirements and focuses on sound products and processes. The C2C life cycle measurements for petroleum-based poly (ethylene terephthalate) (PET) bottles, with an emphasis on different end-of-life options for recycling, were taken for mainland China, in brief. It is considered that the product is manufactured through the extraction of crude oil into ethylene glycol and terephthalic acid. The CML analysis method was used in the LCIA for the selected midpoint impact categories. LCA of the product has shown a drastic aftermath in terms of environmental impacts and energy use. But the estimation of these consequences is always dependent on the system and boundary conditions that were evaluated throughout the study. The impacts that burden the environment are with the extraction of raw material, resin, and final product production. Minor influences occurred due to the waste recycling process. This suggests that waste degradation is the key process to reduce the environmental impacts of the production systems. Lowering a product's environmental impact can be accomplished in a number of ways, including reducing the amount of materials used or choosing materials with a minimal environmental impact during manufacture processes.
ABSTRACT
The widespread use of commercial polymers composed of a mixture of polylactic acid and polyethene terephthalate (PLA-PET) in bottles and other packaging materials has caused a massive environmental crisis. The valorization of these contaminants via cost-effective technologies is urgently needed to achieve a circular economy. The enzymatic hydrolysis of PLA-PET contaminants plays a vital role in environmentally friendly strategies for plastic waste recycling and degradation. In this review, the potential roles of microbial enzymes for solving this critical problem are highlighted. Various enzymes involved in PLA-PET recycling and bioconversion, such as PETase and MHETase produced by Ideonella sakaiensis; esterases produced by Bacillus and Nocardia; lipases produced by Thermomyces lanuginosus, Candida antarctica, Triticum aestivum, and Burkholderia spp.; and leaf-branch compost cutinases are critically discussed. Strategies for the utilization of PLA-PET's carbon content as C1 building blocks were investigated for the production of new plastic monomers and different value-added products, such as cyclic acetals, 1,3-propanediol, and vanillin. The bioconversion of PET-PLA degradation monomers to polyhydroxyalkanoate biopolymers by Pseudomonas and Halomonas strains was addressed in detail. Different solutions to the production of biodegradable plastics from food waste, agricultural residues, and polyhydroxybutyrate (PHB)-accumulating bacteria were discussed. Fuel oil production via PLA-PET thermal pyrolysis and possible hybrid integration techniques for the incorporation of thermostable plastic degradation enzymes for the conversion into fuel oil is explained in detail.