Potentials of GHG reductions from wastewater treatment for the CDM

The study aims to evaluate the potential of GHG （greenhouse gas） reductions by installing an anaerobic digester in a wastewater treatment facility in Southeast Asia. Then the break-even point of additional investment to reduce GHG is obtained by exchanging carbon price as emissions credits. In the project scenario, the wastewater treatment system has the digester, where methane （biogas） is produced and recovered. Compared with the baseline scenario, the biogas has calorific value to produce heat and electricity, and can substitute fossil fuels for power generation. The objective of the study is to define the relationship between CERs （certified emission reductions） and investment costs, and the beak-even point, finding out the dominant pa- rameters in the system. Financial parameters such as capital costs and operating costs are considered to evaluate the investmerit costs. The result shows that the methane recovery reduces 54% of GHG emissions. Although the substitution of the biogas for the fossil fuels reduces only 6% of the GHG emissions, the electricity output can satisfy the electricity consumption. The results also show that the maximum CER credit is 73000 t-COEe/a, and the GHG reduction cost is 14 USD/t-CO2e.

Effect of urban symbiosis development in China on GHG emissions reduction

This paper analyzes current urban symbiosis development and application in China, and then conducts a statistical analysis of the emissions reduction of CO2 and CH4 in relation to recovery of iron and steel scraps, waste paper, and waste plastics from 2011 to 2014 using the greenhouse gas（GHG） emission inventory calculation method provided by the IPCC. Results indicate that the cumulative recovery of renewable resources during China＇s main urban symbiosis development in 2011-2014 was 803.275 Mt, and the amount of iron and steel scraps, waste paper, and waste plastic recovery was the largest, respectively accounting for 62.2%, 18.0%, and 8.2% of total recovery in 2014. In addition, the cumulative emissions reduction of GHGs in relation to recovery of iron and steel scraps, waste paper, and waste plastics in 2011-2014 was27.962 Mt CO2-eq, 954.695 Mt CO2-eq, and 22.502 Mt CO2-eq, respectively, thereby totaling 1005.159 Mt CO2-eq. Results show a remarkable GHG emissions reduction during 2011-2014.

Dilemma and Solutions of Greenhouse Gas Emission Reduction of International Shipping

How to build an international maritime GHG(greenhouse gas)emission reduction cooperation mechanism is an important international issue at present.Firstly,we describe the current situation of maritime transport GHG emission reduction and analyze the problems that still exist in international maritime transport emission reduction from four aspects:political,economic,legal and technical.For example,geopolitical aggravation hinders the solution of the FOC(Flag of Convenience)issue;maritime emissions are not included in the carbon emission trading system;the synergy of maritime emission reduction principles under the IMO(International Maritime Organization)framework and the technical level of maritime emission reduction needs to be improved.The motivation and essence of the divergent international actions on maritime emission reduction are discussed.Finally,it is proposed to implement the“true linkage principle”to solve the problem of FOCs;to promote the development of regional carbon markets and link them to the international maritime carbon emission trading market economically;to implement the CBDR(the common but differentiated responsibilities)principle legally to promote the international emission reduction work in an orderly manner;and the technical innovation of ships and increase the technical support.

Carbon Capture and Storage:History and the Road Ahead

The large-scale deployment of carbon capture and storage(CCS)is becoming increasingly urgent in the global path toward net zero emissions;however,global CCS deployment is significantly lagging behind its expected contribution to greenhouse gas emission reduction.Reviewing and learning from the examples and history of successful CCS practices in advanced countries will help other countries,including China,to promote and deploy CCS projects using scientific methods.This paper shows that the establishment of major science and technology CCS infrastructures in advanced countries has become the main source of CCS technological innovation,cost reduction,risk reduction,commercial promotion,and talent training in the development and demonstration of key CCS technologies.Sound development of CCS requires a transition from pilot-scale science and technology infrastructures to large-scale commercial infrastructures,in addition to incentive policies;otherwise,it will be difficult to overcome the technical barriers between small-scale demonstrations and the implementation of million-tonne-scale CCS and ten-million-tonne-scale CCS hubs.Geological CO_(2) storage is the ultimate goal of CCS projects and the driving force of CO_(2) capture.Further improving the accuracy of technologies for the measurement,monitoring,and verification(MMV)of CO_(2) storage capacity,emission reduction,and safety remains a problem for geological storage.CO_(2) storage in saline aquifers can better couple multiple carbon emission sources and is currently a priority direction for development.Reducing the energy consumption of lowconcentration CO_(2) capture and the depletion of chemical absorbents and improving the operational efficiency and stability of post-combustion CO_(2) capture systems have become the key constraints to largescale CCS deployment.Enhanced oil recovery(EOR)is also important in order for countries to maximize fossil fuel extraction instead of importing oil from less environmentally friendly oil-producing countries.

Implementation of a greenhouse gas reduction roadmap for steel producing companies

This paper shall show an economic feasible approach to implement greenhouse gas(GHG) reduction measures into steel companies. The goal to improve energy consumption is directly linked to the reduction of GHG emissions and therefore directly in correlation with the economic viability. A baseline scenario of the considered reference system and of the respective reference year has to be defined, mapped and analysed. In a second step an analysis of the same operation using available and prospected best available technology (BAT) processes is carried out to generate a basis for a benchmark system. The identified reduction potentials are reported and the GHG emission reductions are put into relation to the investment cost of the new process technologies/process adaption to be implemented.This economic feasibility calculation is necessary to realise a cost efficient GHG reduction roadmap implementation into the company's business operations. The GHG reduction roadmap is developed using the abatement curve concept to get an indication of ' low hanging fruits' and for establishing a sequence for implementing carbon emission reductions measures. The scope of that approach can be extended by including further important environmental parameters like NOx, SO_2,CO,dust,heavy metal emissions in air as well as production residues.That gives in the end a broader picture and more starting points to improve the overall environmental performance of steel producing companies beyond the GHG emissions and energy consumption.

CCS in China:Opportunities, Challenges and Solutions

The economic growth, energy structure and environmental capacity in China determine that CCS (carbon capture and storage) is an important strategic approach for China to confront the climate changes. In this paper, current status in China is firstly presented regarding policy making, technology research and development, pilot project and international cooperation. Then the opportunities of exploring CCS are analyzed from the viewpoint of application potentials, cost and China's circumstances. The challenges to CCS are pointed out with respect to energy consumption, technologies, funding and environment. Finally some suggestions are put forward on CCS development.

Contribution of Multiple Cropping Systems to Greenhouse Gas Mitigation in the Municipality of Abomey-Calavi in Southern Benin

In the world at large, while agricultural yields are increasing with constant land area, in Sub-Saharan Africa, more land is needed to increase production. In this region of Africa, agriculture therefore remains essentially extensive and contributes to environmental degradation, especially deforestation. Thus, the objective of this research is to assess and compare the quantities of greenhouse gases produced by multiple and mono-specific cropping systems. To this end, the quantity of greenhouse gases (GHG) produced by several cropping systems installed on an experimental farm in Kpotomey in the municipality of Abomey-Calavi (Benin) was estimated. The estimation of GHG quantities was made on the basis of IPCC work and data from the experiments carried out. Comparisons were made between mono-specific crops and multiple crops. The results show that the quantities of GHG emitted per ton of production are more or less identical and vary on average from 0.6 to 0.11 teqCO2. However, the advantage of multiple cropping systems is that they reduce the clearing of new land and thus avoid about 31.5 tons of CO2 if the plant formation to be replaced was a forest. Multiple cropping with moderate fertilization in the presence of organic matter increases production while preserving the environment.