Journal of Environmental Engineering Technology•2026•DOI: 10.13205/j.hjgc.202604027
Magnesia production processes generate carbon monoxide (CO) emissions, yet publicly available measured data on CO emission factors for these processes remain scarce, constraining the accuracy of emission accounting and mitigation assessment in the industry. To address this data gap, this study selected three representative magnesia-producing enterprises in Anshan, Liaoning Province, China, covering three typical technological routes: the two-stage calcination process (light burning-briquetting-shaft kiln dead burning), the suspension calcination-dead burning sintering process, and the electric arc furnace melting process. Under the condition that enterprises were not equipped with online CO monitoring modules, an estimation approach coupling manual measurements with conventional indicators from the Continuous Emission Monitoring System (CEMS) was developed. By establishing characteristic concentration ratios between CO and nitrogen oxides (NOx) or particulate matter (PM), and combining them with annual CEMS monitoring data, product-level CO emission factors were calculated. The results showed that the CO emission factors for the two-stage calcination process, the suspension calcination–dead burning sintering process, and the electric arc furnace melting process were 5.35, 5.18, and 1.40 kg/t, respectively, among which the emission level of the electric arc furnace melting process was significantly lower than that of sintering-based processes. This study provides enterprise-level measured CO parameters for the magnesia industry, filling the data gap in emission factors for typical technological routes. It also proposes an emission factor estimation method applicable under conditions where online CO monitoring data are unavailable, which can provide methodological support for pollutant emission accounting and emission inventory development in similar data-constrained industries.
Chinese Journal of Environmental Engineering•2026•DOI: 10.12030/j.cjee.202509093
Amid intensifying global warming, carbon emission reduction and carbon dioxide removal (CDR) have become central to climate governance. In March 2023, the European Commission proposed the Green Claims Directive (GCD) to combat greenwashing and enhance the reliability, comparability, and verifiability of environmental claims. The GCD, together with the Empowering Consumers for the Green Transition Directive, the Carbon Removal Certification Framework, and the European Sustainability Reporting Standards, forms a policy cluster supporting the EU's green transition and CDR deployment. China, as a major greenhouse gas emitter, has made progress in renewable energy and national carbon market construction, yet its total emissions remain high, CDR technologies are nascent, and CCUS deployment is economically oriented, mainly in enhanced oil recovery. This study systematically reviews the legislative background, core objectives, and synergistic logic of the GCD and related policies, focusing on requirements for CDR certification, third-party verification, and carbon credit regulation. It compares Chinese and EU carbon markets in coverage, allowance allocation, and MRV systems. The analysis indicates that EU experience in policy integration, technical standardization, and market maturity can inform China's policy framework, technology pathways, and market efficiency, supporting large-scale CDR and the 'dual carbon' goals.
Journal of Environmental Engineering Technology•2026•DOI: 10.13205/j.hjgc.202608017
Carbon monoxide (CO) is a significant gaseous pollutant emitted during high-carbon ferrochrome (HCFeCr) production, yet measured emission factors for different furnace types remain scarce, hindering accurate emission inventories and pollution control assessments. This study addresses this gap by investigating four typical HCFeCr production facilities in Ulanqab, Inner Mongolia, China, comprising two semi-closed submerged arc furnaces (SAFs) and two closed SAFs. A hybrid methodology combining manual stack sampling and continuous emission monitoring system (CEMS) data was employed. A characteristic CO-to-NOx concentration ratio was established from manual measurements, which was then applied to continuous NOx data to estimate CO emissions and product-based emission factors. Results revealed substantial process-dependent variability: semi-closed SAFs (Facilities A and B) exhibited CO emission factors of 7.06 kg/t and 3.66 kg/t, respectively, whereas closed SAFs (Facilities C and D) with associated pelletizing processes showed notably lower factors of 1.41 kg/t and 0.51 kg/t. On average, semi-closed furnaces emitted approximately six times more CO per tonne of product than closed furnaces. Furnace sealing degree and raw material ratios were identified as key determinants. These findings underscore the inadequacy of using a single average emission factor for HCFeCr production and advocate for furnace-type-specific factors to improve emission accounting accuracy. This study provides essential measured data for developing refined CO emission inventories and supporting pollution reduction policies in the ferroalloy industry.