Emission Mitigation of CO_2 in Steel Industry: Current Status and Future Scenarios

The sustainable development against global warming is a challenge faced by societies at global level. For steel industry; the pressure of reducing CO2 emission is likely to last many years. During the past decades, the CO2 emission per ton steel has been reduced mainly due to the improvement of energy efficiency. Entering the 21st century, the steel manufacturing route must have three functions, namely, production of high performance steel products, conversion of energy, and treatment of waste. In the near future, it is expected that existing BF-BOF and EAF routes will be improved, in order to produce high performance steels, increase the use of scrap, and integrate steel industry with other industries for mitigating CO2 emission. In the long term, using carbon-free energy, reducing agents, and storing CO2 securely or converting CO2 into a harmless substance can be presumed for tremendous reduction in CO2 emission.

Greenhouse gas reduction of co-benefit-type wastewater treatment system for fish-processing industry: A real-scale case study in Indonesia

This study examined the application of co-benefit-type wastewater treatment technology in the fish-processing industry. Given that there was a dearth of information on fish-processing industrial wastewater in Indonesia, site surveys were conducted. For the entire fish-processing industry throughout the country, the dissemination rate of wastewater treatment facilities was less than 50%. Using a co-benefit approach, a real-scale swim-bed technology (SBT) and a system combining an anaerobic baffled reactor (ABR) with SBT (ABR–SBT) were installed in a fishmeal processing factory in Bali, Indonesia, and the wastewater system process performance was evaluated. In a business-as-usual scenario, the estimated chemical oxygen demand load and greenhouse gas (GHG) emissions from wastewater from the Indonesian fish-processing industry were 33 000 tons per year and 220 000 tons of equivalent CO_(2) per year, respectively. On the other hand, the GHG emissions in the co-benefit scenarios of the SBT system and ABR–SBT system were 98 149 and 26 720 tons per year, respectively. Therefore, introducing co-benefit-type wastewater treatment to Indonesia’s fish-processing industry would significantly reduce pollution loads and GHG emissions.

Cropping system innovation for coping with climatic warming in China

China is becoming the largest grain producing and carbon-emitting country in the world,with a steady increase in population and economic development.A review of Chinese experiences in ensuring food self-sufficiency and reducing carbon emission in the agricultural sector can provide a valuable reference for similar countries and regions.According to a comprehensive review of previous publications and recent field observations,China has experienced on average a larger and faster climatic warming trend than the global trend,and there are large uncertainties in precipitation change,which shows a non-significantly increasing trend.Existing evidence shows that the effects of climatic warming on major staple crop production in China could be markedly negative or positive,depending on the specific cropping region,season,and crop.However,historical data analysis and field warming experiments have shown that moderate warming,of less than2.0 °C,could benefit crop production in China overall.During the most recent warming decades,China has made successful adaptations in cropping systems,such as new cultivar breeding,cropping region adjustment,and cropping practice optimization,to exploit the positive rather than to avoid the negative effects of climatic warming on crop growth.All of these successful adaptations have greatly increased crop yield,leading to higher resource use efficiency as well as greatly increased soil organic carbon content with reduced greenhouse gas emissions.Under the warming climate,China has not only achieved great successes in crop production but also realized a large advance in greenhouse gas emission mitigation.Chinese experiences in cropping system innovation for coping with climatic warming demonstrate that food security and climatic warming mitigation can be synergized through policy,knowledge,and technological innovation.With the increasingly critical status of food security and climatic warming,further efforts should be invested in new agricultural policy,knowledge and technology creation,and popularization of climate-smart agriculture,and more financial investments should be made in field infrastructure development to increase cropping system resilience in China.

Greenhouse gas emission and its potential mitigation process from the waste sector in a large-scale exhibition

As one of the largest human activities, World Expo is an important source of anthropogenic Greenhouse Gas emission（GHG）, and the GHG emission and other environmental impacts of the Expo Shanghai 2010, where around 59,397 tons of waste was generated during 184 Expo running days, were assessed by life cycle assessment（LCA）. Two scenarios, i.e., the actual and expected figures of the waste sector, were assessed and compared, and 124.01 kg CO2-equivalent（CO2-eq.）, 4.43 kg SO2-eq., 4.88 kg NO-3-eq., and 3509 m3 water per ton tourist waste were found to be released in terms of global warming（GW）, acidification（AC）,nutrient enrichment（NE） and spoiled groundwater resources（SGWR）, respectively. The total GHG emission was around 3499 ton CO2-eq. from the waste sector in Expo Park, among which 86.47% was generated during the waste landfilling at the rate of 107.24 kg CO2-eq.,and CH4, CO and other hydrocarbons（HC） were the main contributors. If the waste sorting process had been implemented according to the plan scenario, around 497 ton CO2-eq.savings could have been attained. Unlike municipal solid waste, with more organic matter content, an incineration plant is more suitable for tourist waste disposal due to its high heating value, from the GHG reduction perspective.

Profit Analysis by Soil Carbon Sequestration with Different Composts and Cooperated with Biochar during Corn (Zea mays) Cultivation Periods in Sandy Loam Soil

Despite the ability of biochar to enhance soil fertility and to sequester soil carbon, its potential reduction of green house gas emissions and profit analysis with different organic composts and cooperated with biochar for crop cultivation have been a few evaluated. This study was conducted to estimate their greenhouse gas emission reduction and profit analysis by soil carbon sequestration with different organic composts and cooperated with biochar application during corn cultivation periods. For the experiment, the treatments were consisted of aerobic digestate of swine wastes (AD), pig compost as the control (PC), cow compost (CC) and pig compost cooperated with 1% biochar (PC + 1% biochar). The soil texture used in this study was sandy loam, and application rates of chemical fertilizer were 190-39-221 kg·ha-1 (N-P2O5-K2O) as recommended amount after soil test. The soil samples were periodically taken at every 15 day intervals during the experimental periods. It was observed that soil carbon sequestration by AD, CC and PC + 1% biochar application was estimated to be 429 kg·ha-1, 2366 kg·ha-1, and 3978 kg·ha-1, and their CO2-e emission reductions were estimated to be 0.16 tones for AD, 0.87 tones for CC, and 14.58 tones for PC + 1% biochar per hectar for corn cultivation periods. Their profits were estimated at $14.58 for lowest and $451.90 for highest. In Korea Climate Exchange, it was estimated to be $115.20 per hectar of corn cultivation with PC + 1% biochar. So, the price of CO2 per hectar for corn cultivation with PC + 1% biochar was high at 16.8 times relative to cow compost treatment only. For the plant growth response, it was observed that plant height and fresh ear yield were not significantly different among the treatments. Therefore, these experimental results might be fundamental data for assuming a carbon trading mechanism exists for biochar soil application in agricultural practices.

Effects of the nitrification inhibitor nitrapyrin and the plant growth regulator gibberellic acid on yield-scale nitrous oxide emission in maize fields under hot climatic conditions

Nitrification inhibitors are widely used in agriculture to mitigate nitrous oxide(N_(2)O)emission and increase crop yield.However,no concrete information on their mitigation of N_(2)O emission is available under soil and environmental conditions as in Pakistan.A field experiment was established using a silt clay loam soil from Peshawar,Pakistan,to study the effect of urea applied in combination with a nitrification inhibitor,nitrapyrin(2-chloro-6-tri-chloromethyl pyridine),and/or a plant growth regulator,gibberellic acid(GA_3),on N_(2)O emission and the nitrogen(N)uptake efficiency of maize.The experimental design was a randomized complete block with five treatments in four replicates:control with no N(CK),urea(200 kg N ha^(-1))alone,urea in combination with nitrapyrin(700 g ha^(-1)),urea in combination with GA_3(60 g ha^(-1)),and urea in combination with nitrapyrin and GA_3.The N_(2)O emission,yield,N response efficiency,and total N uptake were measured during the experimental period.The treatment with urea and nitrapyrin reduced total N_(2)O emission by 39%–43%and decreased yield-scaled N_(2)O emission by 47%–52%,relative to the treatment with urea alone.The maize plant biomass,grain yield,and total N uptake increased significantly by 23%,17%,and 15%,respectively,in the treatment with urea and nitrapyrin,relative to the treatment with urea alone,which was possibly due to N saving,lower N loss,and increased N uptake in the form of ammonium;they were further enhanced in the treatment with urea,nitrapyrin,and GA_3 by 27%,36%,and 25%,respectively,probably because of the stimulating effect of GA_3 on plant growth and development and the reduction in biotic and abiotic stresses.These results suggest that applying urea in combination with nitrapyrin and GA_3 has the potential to mitigate N_(2)O emission,improve N response efficiency,and increase maize yield.

A green eco-environment for sustainable development:framework and action

Following its 40-year reform and‘Open Door’policy,China has recently proposed a new approach to green development and rural revitalization—the idea of Agriculture Green Development(AGD),with the key feature of creating a green eco-environment.In this minireview we introduce the definition,theory,framework and major components of a green eco-environment as a key part of the AGD.We define a green eco-environment as including four key elements or measures:(1)a green ecoenvironmental indicator system;(2)environmental monitoring and warning networks;(3)emission standards and environmental thresholds for key pollutants;(4)emission controls and pollution remediation technologies.We have used Quzhou County(a typical county in the center of the North China Plain)as an example to show how detailed air,water and soil monitoring networks,as well as improved farmer practices and pollution control measures(especially ammonia emission mitigation and PM2.5 pollution reduction),can begin to create a green eco-environment in China and that AGD is possible.We conclude by stressing the need to improve the framework and practice for a green eco-environment,especially the importance of linking proposals and practices for a green eco-environment with the United Nations high priority Sustainable Development Goals.

Air pollution affects food security in China:taking ozone as an example

Air pollution is becoming an increasingly important environmental concern due to its visible negative impact on human health.However,air pollution also affects agricultural crops or food security directly or indirectly,which has not so far received sufficient attention.In this overview,we take ozone(O3)as an example to analyze the principles and extent of the impact of air pollution on food security in China based on a review of the literature.Current O3 pollution shows a clear negative impact on food security,causing around a 10%yield decrease for major cereal crops according to a large number of field studies around the world.The mean yield decrease of winter wheat is predicted to be up to 20%in China,based on the projection of future ground-level O3 concentration in 2020,if no pollution control measures are implemented.Strict mitigation of NOx and VOCs(two major precursors of O3)emissions is crucial for reducing the negative impacts of ground-level O3 on food security.Breeding new crop cultivars with tolerance to high ground-level O3 should receive serious consideration in future research programs.In addition,integrated soil-crop system management will be an important option to mitigate the negative effects of elevated ground-level O3 on cereal crop production and food quality.