With the rapid development of electric power construction , transmission lines and the surrounding geological environment influence each other that has become increasingly serious, however, there is not formed yet a set of complete and more scientific geological environmental evaluation system in transmission lines at present. In this paper, on the basis of using the experience of other industries of geological environmental evaluation research , study and put forward the geological environmental evaluation method specifically for transmission lines. Evaluation system is established for transmission lines in planning period and construction period , and also put forward the corresponding evaluation index. The research conclusion can provides theoretical support and maintenance for transmission lines of the whole life cycle design,and it also provides reference in designing transmission lines plan and preventing, and controlling geological environmental problems of transmission lines for the decision-making department.
Potential environmental benefits have been identified for the utilization of carbon dioxide (CO2) as a feedstock for polyurethanes (PUR). CO2 can be utilized in the PUR supply chain in a wide variety of ways ranging from direct CO2 utilization for polyols as a PUR precursor, to indirect CO2 utilization for basic chemicals in the PUR supply chain. In this paper, we present a systematic exploration and environmental evaluation of all direct and indirect CO2 utilization options for flexible and rigid PUR foams. The analysis is based on an LCA-based PUR supply chain optimization model using linear programming to identify PUR production with minimal environmental impacts. The direct utilization of CO2 for polyols allows for large specific impact reductions of up to 4 kg CO2-eq. and 2 kg oil-eq. per kg CO2 utilized, but the amounts of CO2 that can be utilized are limited to 0.30 kg CO2 per kg PUR. The amount of CO2 utilized can be increased to up to 1.7 kg CO2 per kg PUR by indirect CO2 utilization in the PUR supply chain. Indirect CO2 utilization requires hydrogen (H2). The environmental impacts of H2 production strongly affect the impact of indirect CO2 utilization in PUR. To achieve optimal environmental performance under the current fossil-based H2 generation, PUR production can only utilize much less CO2 than theoretically possible. Thus, utilizing as much CO2 in the PUR supply chain as possible is not always environmentally optimal. Clean H2 production is required to exploit the full CO2 utilization potential for environmental impact reduction in PUR production.
Energetic and environmental evaluation of two molecular diagnostic systems for COVID-19
