活性炭纤维净化印刷过程产生的VOCs废气

介绍了应用局部排气的方法,收集印刷过程的挥发性有机化合物(VOCs)废气,应用活性炭纤维(ACF)吸附脱附有机废气回收净化装置,进行印刷厂VOCs废气的回收与治理,详细描述了印刷车间VOCs废气的收集与处理工艺过程及其效果.测试结果表明,应用此工艺和设备可以有效地进行印刷过程大风量的VOCs废气的回收和治理.     

化学原料药行业挥发性有机废气污染特征与治理中的主要问题及建议

化学原料药制造行业是挥发性有机废气(VOCs)排放重点监管行业。原料药生产过程中VOCs排放具有排放节点多、成份复杂等特点。在阐述典型原料药生产过程中VOCs产生环节的基础上,分析了制药企业VOCs治理普遍面临的治理技术缺乏针对性、无组织废气收集不足、企业废气自行监测能力不足等难点问题,并对制药企业VOCs治理提出了加强有机废气成分溯源监测和规范废气收集等前瞻性建议,以期为提高该行业的VOCs治理效果并促进制药行业的可持续发展提供参考。     

防火及阻燃材料质量检验过程中含挥发性有机物烟气的治理工艺

防火及阻燃材料的质量检验是检验产品防火性能、有效预防火灾的保障,在其检验过程中会产生大量含挥发性有机物(VOCs)的烟气,该类废气通常未经处理或经简单处理直接排放,严重污染了周围环境。为研究该类废气的排放状况,分析了该类废气的成份及特点。通过对比分析VOCs废气处理的常用治理工艺,结合实际工程应用经验,针对性的提出了该类废气的综合治理工艺,为该类废气的治理提供了参考。     

印刷环节挥发性有机物无组织排放特征测定研究

对使用溶剂型油墨的凹版印刷设备和使用水性油墨的柔版印刷设备无组织排放的挥发性有机物(VOCs)浓度进行了实际监测,并采用计算流体动力学模拟无组织排放VOCs的收集效率.结果表明:(1)使用溶剂型油墨的凹版连续印刷过程非甲烷总烃(NMHC)最高均值达到5975.67 mg/m3,约为使用水性油墨的柔版印刷(191.67 ...     

不同工作模式下VOCs废气收集系统阻力平衡数值模拟与应用

为了提高平版印刷车间不同工作模式下VOCs废气收集系统的收集效率和降低收集系统的能耗,采用支路管道上增设调节阀和集气罩罩口增设三角板的联合措施,并通过数值模拟的方法对废气收集系统进行阻力平衡优化,使得各支路和集气罩罩口风量达到设计风量。将各集气罩模拟风量与实测风量进行比较,发现二者具有较高的吻合性,从而证明了数值模拟方法的可靠性。模拟结果表明:在全负荷运行模式下,经优化后,系统支路最大风量偏差与最大阻力不平衡率由原设计的41.81%和23.77%降至为0.26%和0.43%,优化后各集气罩风量偏差能够控制在-0.2%～0.3%;在不同工作模式下,优化后收集系统均已基本达到全平衡负压状态,各工作支路阻力偏差在0%～0.43%,各支路和集气罩能够实现在设计状态下运行。本研究结果可为VOCs废气收集系统的优化与运行提供参考。     

微波催化燃烧技术处理印刷包装行业VOCs

微波催化燃烧技术将微波辐照与吸波型催化剂相结合,可用于对挥发性有机化合物(VOCs)进行催化燃烧处置.研制了 Pt/CuMnCeOx/堇青石和Pt/CuMnCeOx/纳米陶瓷整体式蜂窝状催化剂,并开发了微波催化燃烧VOCs的装置,将其应用于印刷包装行业的VOCs治理.通过操作条件的优化,考察了微波催化燃烧技术对VOCs...     

加油站的烃类VOCs污染及其治理技术

加油站因储运轻质油品而产生的烃类VOCs对健康、环境、安全以及油品质量等带来了一系列负面影响.发达国家的常规治理措施主要是进行密闭卸油和密闭发油,对加油站的设备安装、管线布置、运营管理等都有一些具体要求;进入21世纪后美国又提出了强化加油站油气回收处理的观点,相应的技术、设备及法规也都日益健全.国内目前对加油站烃类VOCs污染的治理工作与发达国家相比差距很大,应该尽快从烃类VOCs回收处理的专用膜分离装置入手进行相关研究和产品开发.     

糖用活性炭生产中工艺废气的治理和回收磷酸

介绍了转炉磷酸法生产糖炭过程中工艺废气的治理方法，采用三级吸收治理废气，回收了其中有用的磷酸废气，获得了较好的环境效益和社会效益。     

典型石化企业挥发性有机物排放测算及本地化排放系数研究

石化行业是中国大气挥发性有机物(VOCs)的重要来源。以中国某新建典型石化企业为例,综合采用不同核算方法估算并比较了石化企业典型排放环节VOCs的排放结果;并在此基础上计算了石化企业典型排放环节本地化排放系数。结果表明,典型石化企业各环节VOCs排放量贡献分别为:储罐50.4%、废水收集与处理29.0%、火炬8.3%、装卸5.2%、设备密封点3.4%、循环冷却水2.4%、燃烧烟气0.8%、工艺废气0.5%;在装卸、设备密封点、废水收集与处理、循环冷却水环节,不同核算方法造成核算结果差异较大,排放系数法核算结果为本研究方法核算结果的数倍,其中装卸过程为4.2倍(无回收设施)和16.4倍(含回收设施),设备密封点为4.4倍(泄漏筛分法)和55.4倍(相关方程法),废水收集与处理为2.1倍,循环冷却水为2.1倍;《大气挥发性有机物源排放清单编制技术指南》中石油炼制企业的VOCs排放系数为本研究1.8倍,因此石化企业在建立排放清单时应开展本地化研究,建立本地化系数;研究结果对于中国建立石化企业VOCs排放清单提供了一定支撑。     

环丙胺生产中工艺废气的治理

遂昌精细化工厂是一家生产环丙沙星药物中间体环丙腔的企业,年生产能力300t环丙胺,产品80％左右外销。在生产环丙胺过程中排放出二氧化硫、氯化氢和氨等大量工艺废气。该厂虽然采用碱性废水进行吸收处理,但由于废水pH值变化较大,二氧化硫和氨等废气治理效果不理想。笔者对环丙胺生产过程中产生的工艺废气排放情况、回收利用等问题进行研究,设计了一套环丙胺生产工艺废气的治理与利用方案。根据设计方案建成的治理设施已在选昌精细化工厂投入运行。实践证明,采用该治理方案能有效地解决环丙胺生产过程中工艺废气对周围环境的污染。1环…     

次氯酸钠发生器的研制

介绍了电解法生产次氯酸钠的原理 ,并在原有生产工艺的基础上进行了重新设计和对设备的重新选择、改造 ,得出了各个工艺参数的最佳值 ,生产出高品质的次氯酸钠     

Estimation of uncertainty of sampling for analysis of pesticide residues

Abstract

A computer model was used to take random samples from primary sample populations obtained from field trials to simulate the uncertainty of sampling for residue analysis of plant commodities and soil. The results indicate about 40%, 30% and 20% relative uncertainty when random samples of size 5, 10 and 25 are taken respectively, from a single lot. Therefore the sample size should be the same for establishing and enforcing legal limits.     

Evaluation of the presence of drugs of abuse in tap waters

A total of seventy samples of drinking water were tested for non-controlled and illicit drugs. Of these, 43 were from Spanish cities, 15 from seven other European countries, three from Japan and nine from seven different Latin American countries. The most frequently detected compounds were caffeine, nicotine, cotinine, cocaine and its metabolite benzoylecgonine, methadone and its metabolite EDDP. The mean concentrations of non-controlled drugs were: for caffeine 50 and 19 ng L⁻¹, in Spanish and worldwide drinking water respectively and for nicotine 13 and 19 ng L⁻¹. Illicit drugs were sparsely present and usually at ultratrace level (<1 ng L⁻¹). For example, cocaine has mean values of 0.4 (Spain) and 0.3 ng L⁻¹ (worldwide), whereas for benzoylecgonine, these mean values were 0.4 and 1.8 ng L⁻¹, respectively. Higher concentrations of benzoylecgonine were found in Latin American samples (up to 15 ng L⁻¹). No opiates were identified in any sample but the presence of methadone and EDDP was frequently detected. Total mean values for EDDP were 0.4 ng L⁻¹ (Spain) and 0.3 ng L⁻¹ (worldwide). Very few samples tested positive for amphetamines, in line with the reactivity of chlorine with these compounds. No cannabinoids, LSD, ketamine, fentanyl and PCP were detected.     

不同泥源对厌氧氨氧化反应器启动的影响

采用2套上流式生物膜反应器,分别接种少量厌氧氨氧化污泥和大量硝化污泥,考察其对厌氧氨氧化反应器启动的影响。污泥接种入反应器后,测得接种厌氧氨氧化污泥的反应器(R1)内MLSS为0.22 g/L,另一个反应器(R2)MLSS为2.7 g/L。与直接接种厌氧氨氧化污泥相比,R1经过72 d的运行才显现出厌氧氨氧化特性。经过114 d的培养,前者氮去除速率由0.23 kg/(m3.d)提升到5.29 kg/(m3.d),总氮去除率大于89%;R2的氮去除速率由0.01 kg/(m3.d)提升到1.1 kg/(m3.d),总氮去除率大于84.6%。说明普通污泥启动需要一个较长的筛选过程,直接接种少量的厌氧氨氧化污泥比接种普通的污泥能够更快启动厌氧氨氧化反应器。     

An application of the theory of kinematics of mixing to the study of tropospheric dispersion

The most common technique used for numerical simulations of tracer mixing is that of the numerical solution of the advection–diffusion equation with the unresolved fluxes parameterized using the similarity theory. Despite correct predictions of the overall directions of transport, models based on a numerical solution of the advection–diffusion equation lack sufficient accuracy to correctly reproduce the coupling of mixing with small scale processes which are sensitive to the microstructure of the tracer distribution. The objective of this paper is to revisit the basic formalism employed in numerical models used to investigate atmospheric tracers. The main mathematical method proposed here is the theory of kinematics of mixing which could be applied effectively for simulations of atmospheric transport processes. At the beginning of the paper, we introduce simple mathematical transformations in order to demonstrate how complex topological structures are created by mixing processes. These idealistic flow systems are essential to explain transport properties of much more complex three-dimensional geophysical flows. An example of the application of the kinematics of mixing to the analysis of tracer transport on a planetary scale is presented in the following sections. The complex filamentary structures simulated in the numerical experiment are evaluated using some commonly applied statistical measures in order to compare the results with the data published in the literature. The results of the experiment are also analysed with the help of simple conceptual models of fluid filaments. The microstructure of the tracer distribution introduced in the paper is essential to increase our understanding of atmospheric transport and to develop more realistic parameterizations of small-scale mixing. The presented results could also be used to improve calculations of the coupling between microphysical processes and tracer mixing.     

Mechanisms of biodegradation of dibenzoate plasticizers

Biodegradation mechanisms were elucidated for three dibenzoate plasticizers: diethylene glycol dibenzoate (D(EG)DB), dipropylene glycol dibenzoate (D(PG)DB), both of which are commercially available, and 1,6-hexanediol dibenzoate, a potential green plasticizer. Degradation studies were done using Rhodococcus rhodochrous in the presence of pure alkanes as a co-substrate. As expected, the first degradation step for all of these systems was the hydrolysis of one ester bond with the release of benzoic acid and a monoester. Subsequent biodegradation of the monobenzoates of diethylene glycol (D(EG)MB) and dipropylene glycol (D(PG)MB) was very slow, leading to significant accumulation of these monoesters. In contrast, 1,6-hexanediol monobenzoate was quickly degraded and characterization of the metabolites indicated that the biodegradation proceeded by way of the oxidation of the alcohol group to generate 6-(benzoyloxy) hexanoic acid followed by β-oxidation steps. This pathway was blocked for D(EG)MB and D(PG)MB by the presence of an ether function.The use of a pure hydrocarbon as a co-substrate resulted in the formation of another class of metabolites; namely the esters of the alcohols formed by the oxidation of the alkanes and the benzoic acid released by hydrolysis of the original diesters. These metabolites were biodegraded without the accumulation of any intermediates.     

造纸废水混凝处理中SFT助凝替代性研究

中小造纸厂废水处理常用PAC作混凝剂 ,PAM作助凝剂。由于PAM成本很高 ,影响了处理设备的投运率。用超细滑石粉 (SFT)替代PAM助凝 ,与混凝剂PAC配合 ,其混凝处理效果基本相当 ,但是处理成本降低 0 .10元 /m3 。由于SFT属环境无害材料 ,不会给排泥带来二次污染     

混凝试验搅拌器的研制

影响混凝效果的因素众多,混凝沉淀烧杯试验是进行水的混合、絮凝、沉淀工艺研究、设计和生产指导的最有效方法之一,阐述了智能型混凝试验搅拌器的设计原理和技术性能.     

产油微藻培养与回收的关键技术研究进展

寻找廉价而高效的替代原料是实现生物柴油产业化的关键所在.微藻以含油量高、生长周期短、环境适应能力强、生物产量高等优点,有望成为一种极具潜力的生物柴油生产原料.然而,目前尚存在微藻培养低效成本高和微藻回收效率低两大难题.综述了微藻培养与回收过程中的关键技术,并对存在的两大难题及其改进技术进行了详细的探讨.最后,总结并展望了微藻培养、回收技术未来的发展趋势.     

生物质快速热裂解主要参数对生物油产率的影响

以松木木屑为原料,在自制的小型流化床上,开展了生物质热裂解温度、生物质粒径和进料速率对生物油产率的影响实验研究.结果表明,在热裂解温度分别为450、475、500、525和550℃条件下,当热裂解温度为500℃时,生物油产率最高,平均产率达到53.33%（质量百分比）.反应温度越高,炭产量越低,不可冷凝气体产量越高,气体发热值越高;粒径＜1 mm的生物质其粒径对生物油产率影响不大;生物质进料速率增加时,生物油产率增加.本研究为生物能的利用提供了新的途径.