延迟焦化装置非密闭除焦工序职业病危害程度分析

目的 了解延迟焦化装置非密闭除焦工序职业病危害程度.方法 选取某大型炼化企业延迟焦化装置一套,通过现场调查,确定非密闭式除焦工序存在的主要职业病危害因素及其接触岗位,对职业病危害因素进行检测,评判并分析各岗位化学有害因素职业接触水平,确定职业病危害程度.结果 除焦工岗位接触硫化氢、粉尘危害因素检测结果超标,装车工接触粉尘危害因素检测结果超标.除焦工硫化氢、粉尘接触水平均为Ⅳ级,装车工粉尘接触水平为Ⅳ级.结论 加强延迟焦化装置非密闭除焦工序个人使用的职业病防护用品的配备,新建延迟焦化装置应尽量选择密闭除焦技术,当前运行的存在非密闭除焦工序的延迟焦化装置应进行工艺技术改造.     

汾渭平原复杂地形影响下冬季PM2.5污染分布特征、来源及成因分析

汾渭平原受其复杂地形特征及产业结构影响,和京津冀、长三角地区一起被列为大气污染重点防治区域.本研究应用2014—2019年冬季中国环境监测总站汾渭平原各城市的六大空气污染物逐小时数据,结合欧洲中心ERA-5数据,利用HYSPLIT后向轨迹模型及T-model斜交旋转主成分分析法（PCT）,揭示过去6年汾渭平原冬季颗粒物浓度演变规律,厘清汾渭平原复杂地形影响下大气污染来源特征、潜在源区及成因,识别影响汾渭平原冬季空气污染的主要天气系统类型.HYSPLIT模拟结果表明,冬季喇叭口地形城市主要受本地和邻近区域污染源影响;山区盆地地形城市更易受到100~300 km距离以内污染源的传输影响,其中,来自陕北的气团对其影响最大;峡谷地形城市更易受到300~600 km范围内污染源的传输影响;平原地形城市的污染物浓度受区域传输的影响较大.影响汾渭平原冬季颗粒物重污染的天气系统可分为高压前部型、高压后部型、均压场型及低压倒槽型,其中,高压前部型是汾渭平原冬季重污染时段最易出现的天气形势.     

A highly porous animal bone-derived char with a superiority of promoting nZVI for Cr(VI) sequestration in agricultural soils

Paddy soil and irrigation water are commonly contaminated with hexavalent chromium [Cr(VI)] near urban industrial areas, thereby threatening the safety of agricultural products and human health. In this study, we develop a porous and high specific area bone char (BC) to support nanoscale zero-valent iron (nZVI) and apply it to remediate Cr(VI) pollution in water and paddy soil under anaerobic conditions. The batch experiments reveal that BC/nZVI exhibits a higher removal capacity of 516.7 mg/(g?nZVI) for Cr(VI) than nZVI when normalized to the actual nZVI content, which is 2.8 times that of nZVI; moreover, the highest nZVI utilization is the nZVI loading of 15% (BC/nZVI15). The Cr(VI) removal efficiency of BC/nZVI15 decreases with increasing pH (4 – 10). Coexisting ions (phosphate and carbonate) and humic acid can inhibit the removal of Cr(VI) with BC/nZVI15. Additionally, BC exhibits a strong advantage in promoting Cr(VI) removal by nZVI compared to the widely used biochar and activated carbon. Our results demonstrate that reduction and coprecipitation are the dominant Cr(VI) removal mechanisms. Furthermore, BC/nZVI15 shows a significantly higher reduction and removal efficiency as well as a strong anti-interference ability for Cr(VI) in paddy soil, as compared to nZVI. These findings provide a new effective material for remediating Cr(VI) pollution from water and soil.     

海上溢油指纹鉴别技术现状及展望

简要回顾了海上溢油污染概况,介绍了国内外溢油鉴别方法:气相色谱法、气相色谱-质谱法、荧光光谱法、红外光谱法等,指出了未来海上溢油指纹鉴别技术的发展方向。     

On-line batch production of ferrate with an chemical method and its potential application for greywater recycling with Al(III) salt

Ferrate(VI) salt is an oxidant and coagulant for water and wastewater treatment. It is considered as a possible alternative method in greywater treatment. However, challenges have existed in putting ferrate(VI) technology into full-scale practice in water and wastewater treatment due to the instability of ferrate solution and high production cost of solid ferrate products. This study demonstrated a new approach of greywater treatment with on-line batch production of Fe(VI) to which Fe(III) salt was oxidized at a weak acidity solution. A series of experiments were conducted to investigate the effect of Fe(VI) on light greywater (total organic carbon (TOC) = 19.5 mg/L) and dark greywater (TOC = 55 mg/L) treatment under different conditions with varying pH and Fe(VI) doses. In addition, the combination use of Fe(VI) and Al(III) salts was proved to be more efficient than using the Fe(VI) salts alone at greywater recycling. The optimum dosage of Fe(VI)/Al(III) salts was 25/25 mg/L for light greywater, 90/60 mg/L for dark greywater, respectively. The TOC values of both light greywater and dark greywater were reduced to less than 3 mg/L with the dosages. The cost for treating greywater was 0.06–0.2 $/ton at ferrate(VI) dosage of 25–90 mg/L and 0.008–0.024 $/ton at AlCl₃ dosage of 25–60 mg/L. The full operating cost needs further assessment before the Fe(VI)/Al(III) technology could be implemented in greywater treatment.     

Dynamic equity carbon permit allocation scheme to limit global warming to two degrees

Significant international collaboration is required to limit global temperature increase to below 2 °C above pre-industrial levels. Equity is the foundation of cooperation, and therefore, this study proposed a new dynamic carbon permit allocation scheme based on four principles: equality, historical responsibility, capability, and future development opportunities. Decision makers could have different preferences for allocating carbon permits, therefore, four equity rules or indicators (equality, responsibility, capacity, and sovereignty) were assigned different weights. Based on the global carbon budget of the 2 °C target, emission permits were calculated and relevant economic implications analyzed using the Global Change Assessment Model. Results indicated that developed countries should reduce emissions immediately, while allowances for developing regions could permit an initial increase in emissions until peaking. Applying different weights to the indicators resulted in multifarious regional allowances. Developed regions would benefit from the “preferring sovereignty” scenario and most developing countries would benefit under the “preferring responsibility” and “preferring capacity” scenarios. Compared with the Intended Nationally Determined Contributions submitted to the United Nations Framework Convention on Climate Change, this study found that in the short term, developed countries might insist on sovereignty as the preferred indicator. However, preferring sovereignty would place substantial mitigation pressures on developing countries in the long term. Therefore, in addressing global climate change, a dynamic choice in the weighting distribution for different indicators might be conducive to international agreement. Furthermore, a market-based trading instrument could help all participants both mitigate global climate change by reducing regional and global costs and facilitate mitigation capital flow from developed to less developed regions.     

面向制信息权的核污染扩散预警技术研究

以核电站核污染扩散预警技术为研究对象,基于环保指挥自动化系统C4ISRE,通过整合WRF、HYSPLIT、Unidata IDV、AGI STK、Arc GIS系统等构建核污染扩散单一合成图SIP(Single Integrated Picture),并通过SIP对核污染扩散进行详细分析,进而实现对核污染应急处置的制信息权。研究表明:当研究区实际的天气系统具备了本例模拟的气象特征时,即主体风向为局部区域东北风3~4级,局部区域西北风6~7级,发生与日本福岛核事故同样等级的事故,12个小时后,受影响的居民区主要为谢屯镇、炮台镇、李店镇、普兰店市、无名区1。其中,炮台镇的大部分区域浓度为10 Pbq,面积为2.66 km 2,东北方向部分区域浓度为100 Pbq,面积为0.03 km~2;普兰店市西南部区域浓度为10 Pbq,面积为8.00 km~2,东北部区域浓度为100 Pbq,面积为0.033 km 2;李店镇东北区域浓度为1 Pbq,面积为0.93km~2;无名区1南部区域浓度为1 Pbq,面积为4.50 km~2。