Comprehensive analysis on the economy and energy demand of pressure-swing distillation and pervaporation for separating waste liquid containing multiple components

A large amount of waste liquids containing methanol/acetone/water mixtures are produced in the synthesis of methyl methacrylate(MMA).Under the advocacy of green chemical industry,it is urgent to develop an efficient,economic and energy-saving mixture separation process.Through thermodynamic azeotropic behavior and pressure sensitivity analysis,pressure-swing distillation was determined and the optimal separation pressure of each column in the process was obtained.Due to the composition of waste liquids produced were quite different in MMA production,the pressure-swing distillation separation process was designed to fully achieve the accurate waste liquids treatment.Taking the total annual cost(TAC)as the target,the sequential iteration method was used to optimize the process,and the impact of composition on economy was compared.In order to further realize the energy-saving of the separation process,the pervaporation membrane module was introduced to pretreat the waste liquid in the pressure-swing distillation.The results showed that the TAC of the coupling process was 46% higher than that of the pressure-swing distillation process,and the thermodynamic efficiency was 30% higher.This study provides waste liquid treatment technology for enterprises and analyzes its economic and energy efficiency,which has reference significance for the development of coupled separation technology.

Bulgaria,Boosting Energy Cooperation with China——Interview with Deputy Minister Yaneva,Ministry of Economy and Energy,the Republic of Bulgaria

Deputy Minister Yaneva of Economy and Energy,the Republic of Bul- garia,a nice lady with outstanding talents,headed a delegation of Bulgaria to visit China in late June,for the participation at the 13th Bulgarian-Chi- nese Intergovernmental Commission for Economic,Trade,Scientific and Technical Cooperation.As an important instrument,the Joint Commission played a significant role in promoting the overall development of the bilat- eral economic relations. China's Foreign Trade interviewed Deputy Minister Yaneva and she gave very constructive suggestions on promoting the bilateral economic and trade cooperation between the two countries,especially in the area of energy cooperation.The following is a written interview with Deputy Min- ister Yaneva.

Modeling Assessment of Renewable Energy to Design Business Plans of Power Options Aimed Energy Planning

The objective of this paper is the evaluation of business opportunities attractiveness in RER （renewable-energy resources） within a specific geographic area, and using some concepts of integrated energy-resource planning. The proposed methodology includes the main figures of economic merit evaluated to each resource assessed, the sensitivity analysis on cash flow, and recommendations of investments to each energy option assessed. A study case is applied within the northwest region of Sao Paulo State （Brazil） for those renewable-energy options. Five options of renewable-energy resources were chosen to be evaluated： three ERs （energy resources） from supply side （small hydro, wind farms and sugarcane bagasse） and two ERs from demand side （replacement of incandescent lighting by fluorescent and replacement of electric showers by central heating systems）. The conclusion is that, only two assessed ERs that have received investment grade were sugarcane biomass and fluorescent lamps replacing incandescent lamps. The rest have restriction due different reasons listed.

THE RISK AND ECONOMY ANALYSIS OF ENERGY DISSIPATORS

According to the analysis results of risk,economy and practical experiences for many years,the paper demonstrates that the great economic benifits can be got by reducing the design flood standard of energy dissipators and that the reduction of design flood standard is significant for reducing project investment and speeding project construction.

China and the United States’ Critical Roles in Tackling Climate Change and Shaping the International Regimes

This paper argues that major powers can play critical roles in a complicated regime system,as evidenced by China and the U.S.which have had pivotal influence in the construction of the post-2020 climate regime.China and the U.S.have participated in multilateral consultations beyond the scope of the United Nations Framework Convention on Climate Change(UNFCCC)while making use of many political platforms,such as Asia-Pacific Economic Cooperation(APEC),G20,and informal meetings and dialogues to bridge the gap among various approaches to mitigating climate impacts.China-U.S.bilateral cooperation has incorporated energy and climate issues into the strategic and economic dialogue(S&ED)and launched other schemes,such as EcoPartnerships and wide-ranging dialogues and initiatives on clean energy/clean vehicles.These schemes support the reconciliation of ideas related to domestic abatement policies in the areas of energy,climate change,and environmental protection.Since the Trump administration came to power in 2017,the bilateral cooperation at national level has been retreated significantly and therefore slowdown the UN’s institutional response to climate change.At the stage,the U.S.may not be able to play a critical role in shaping the regime,yet China is regarded to be the most important player in negotiations under the Paris Agreement.

On the Developing Strategy of Taiyuan in the Growing-up of the Middle Area

It is urgent that how the middle part of China plays its unique role during the development process of northeast, west and east area. This paper analyses the environment pollution problems caused by economic development of Taiyuan and points out that Taiyuan should accurately locate and seize the opportunities for the growing-up of the west area and make Taiyuan become one of the economic growth poles in the central China.