1、Practical Applications of Control Strategies控制措施应用实例,Topics to be Discussed 讨论内容,Addition of hydrated lime to cyanide tanks 向氰化物提取罐添加熟石灰Respirable silica during sand blasting 喷砂处理产生的呼吸性矽尘Ventilation in a laboratory sample room 实验室样品间的排风系统Mercury exposure in a gold room 炼金室的水银污染Manufacture of phthali
2、c anhydride 生产邻苯二甲酸酐Control of powders in the pharmaceutical industry 制药业对粉末的控制Diesel particulate in underground coal mines 地下煤矿的柴油微粒,Addition of Hydrated Lime to Cyanide Tanks向氰化物提取罐添加熟石灰,At a carbonpulp gold processing plant in Equatorial Africa, the need arose to make routine additions of hydrate
3、d lime (Ca(OH)2) to the cyanide extraction tanks in order to control pH 一家位于赤道非洲使用含碳矿浆法的炼金厂，需要向氰化物提取罐中例行添加熟石灰（ Ca(OH)2 ）以控制罐内pH值To do this the mill decided to use bulk hydrated lime delivered to the site in 1000kg bulk bags so as to minimise transportation costs为此，该厂决定使用散装的熟石灰，为了最大限度地降低成本，这些熟石灰装在100
4、0公斤一个的集装袋中运往工地,Addition of Hydrated Lime 添加熟石灰,The pH in the tanks was monitored and when required a 1000kg bag was lifted by crane above a chute which had an internal spear to pierce the bag and release the hydrated lime to the cyanide mixing tanks below提取罐内的pH值是受到监控的，必要时起重机会将1000公斤的单个熟石灰袋吊至溜槽上，用该溜
5、槽上自带的锥刺破外袋，并向下方的氰化物混合罐中倾倒熟石灰This process generated significant levels of dust这一过程会产生大量的粉尘,Process of Adding Hydrated Lime熟石灰的添加过程,Source: University of Wollongong,Properties of Hydrated Lime熟石灰的属性,Reference to the product MSDS indicated that the material was corrosive by inhalation, ingestion, skin
6、and eyes 据材料安全数据表（MSCS）显示，熟石灰对呼吸道、消化道、皮肤和眼部都有腐蚀作用Inhalation would result in severe mucous membrane irritation of the nose and throat and prolonged and repeated contact with the skin would result in a severe skin rash, dermatitis and possible chemical ulceration人体吸入熟石灰会导致严重的鼻、喉部的粘膜产生强烈的刺痛感，而皮肤长期不断地同熟
7、石灰接触会引发严重皮疹、各种皮肤病，甚至有可能化学性溃烂。,Initial Issues首要问题,When the process initially commenced, operators experienced respiratory irritation and due to the hot humid equatorial climate, severe skin irritation and in one case, ulceration这一过程一开始，操作员就得承受呼吸道不适再加上炙热的赤道气候对皮肤的刺激，甚至还出现过一例皮肤溃烂。,Initial Control Measur
8、es初级控制措施,The response of the mill manager (an expatriate from North America) was to supply respiratory protection and impervious raincoats so that the product didnt contact the skin 当时，炼金厂经理（一位北非侨民）采取的措施是给操作员提供呼吸保护设备和防止物料与皮肤接触的厚雨衣。 This was a practice that had previously been used during an emergenc
9、y at a mill in a cold North American location这种方法是过去在气候寒冷的北美洲地区的工厂采用的应急措施,Secondary Issues衍生问题,Initial issues of respiratory however有关呼吸系统和皮肤不适的首要问题在很大程度上得到了解决；然而Almost immediately that the initial control procedures were introduced the number of heat stress cases presenting to the onsite clinic inc
10、reased 几乎就在初步的防护措施得到应用的同时，工地诊所里中暑病例的数量也上升了,Results of Investigation调查结果,Upon investigation it was realised that the combination of impervious raincoats and a hot equatorial climate had resulted in the operators core body temperature increasing to the point of heat stress onset调查表明，在严实的雨衣和炙热的赤道气候双重作用
11、下，操作员体温升高，以致中暑This had not occurred in the North American location when the same approach was previously used, due to the cold climate 北美以前用这种方法的时候从来没有出现过上述问题，因为那里的气候寒冷。,Final Solution 最终方案,Management response was to temporarily cease the addition of the hydrated lime in bulk bags until a series of
12、fine water sprays could be installed inside the delivery chute管理层的反应是临时叫停大袋熟石灰的添加工序，直到给传送溜槽内部安装一套理想的喷水装置 Once the spray system was activated the fine dust arising from the opening of the bags was contained, eliminating the need for any personal protective equipment一旦启动了喷水装置，袋子破口处扬起的细石灰粉尘就受到了抑制，也就用不着
13、任何的个人防护用具了,Key Learnings 重要经验,Need to consider all aspects of the process when evaluating a control solution在评估控制方案时需要综合全面地考虑整个生产过程What works in one location may not be transferable to another照搬其它地方的现成做法可能会适得其反Incorrect use of PPE can lead to a dangerous situation个人防护用具使用不当也会导致危险,Respirable Silica E
14、xposure During Sand Blasting喷砂产生的呼吸性矽尘污染,Sand blasting (or more correctly, grit blasting) is a common practice in industry to prepare steelwork for painting, welding or further processing喷沙（或者说喷砂更准确）是工业生产中为钢件的涂漆、焊接或进一步加工做准备的一种常规技术The term “sand blasting” is derived from the period when river or beac
15、h sand was forced at high pressure through a nozzle so as to clean surfaces “喷砂”这个术语源于用高压喷嘴向工件喷射河砂，或海滩砂粒，以清理工件表面的这一工艺过程。,Sand Blasting 喷砂,The high velocities involved in sand blasting results in the sand particles fracturing, thus reducing the particle size to the point that it could be respired by
16、the operator.喷砂的超高速度使得砂粒粉碎，从而把砂粒切割到操作员可以吸入体内的粒度Many operators of such systems who were not adequately protected suffered silicosis and in some cases, death许多此类工作的操作员因为没有采取足够的防护措施，因而患上了矽肺病，更有致死的病例,Modern Practice当代采取的措施,To overcome the issue of silicosis, statutory authorities in many countries banne
17、d the use of sand, and low silica products such as garnet, ilmenite and copper slag were substituted为克服矽肺病难题，许多国家的司法机关禁止了采用砂砾进行喷砂，转而使用低硅材料，比如石榴石、钛铁矿和铜矿渣。,Workplace Situation 工作现场环境,An occupational hygienist was visiting a construction site and observed significant dust clouds arising from a grit bla
18、sting operation曾经有一位职业卫生专家，在检查某建筑工地时，发现了由喷砂导致的巨大扬尘Upon closer investigation it was found that the material being used in the process was a fine dust containing 35%w/w crystalline silica as it was a cheap source of blasting material经过细致的调查，该喷砂工序采用的材料是一种极细的砂砾，其中含有35%w/w的石英，就因为它价格低廉,Workplace Situation
19、 (cont)工作现场环境（续）,Source: University of Wollongong,Workplace Situation (cont)工作现场环境（续）,The airline respirator being used by the operator was found to be in poor condition and the air compressor being used for the blasting process was also the air supply for the air supplied respirator 调查发现现场操作员使用的是极差
20、的民航呼吸器，并且喷砂使用的空气压缩机同时也是呼吸器的气源No air quality monitoring results from the supplied air could be found没有查到任何呼吸器气源质量的监控记录,Workplace Situation (cont)工作现场环境（续）,Discussions with the operators assistant indicated that it was not uncommon for the dust cloud from the blasting operation to drift over the posit
21、ion where he was shovelling the silica material into a supply hopper 专家在与操作员助手讨论后得知，在他将硅料铲入时，喷砂产生的扬尘飘出加料斗是司空见惯的事情No respiratory protection had been supplied to this person该工地没有向这位助手提供呼吸器,Occupational Hygienists Response职业卫生专家的建议,Process stopped immediately 立即停止作业Substitution of sand with more approp
22、riate product喷砂应使用更理想的材料Independent air supply for airline respirator with regular air quality monitoring呼吸器须采用独立气源，并定期监控气源质量Introduction of a wind barrier to minimise wind drift引入挡风设施，把风吹引起的扬尘控制在最小程度Introduction of an educational program for all employees建立针对所有员工的安全卫生教育计划,Key Learnings 重要经验,The nee
23、d to understand the nature of products being used in a process and the effect the process may have in increasing the risk of a health hazard必须了解生产使用的每一种物料的属性以及每一种生产工艺对人体健康的威胁程度Consideration needs to be given to all potentially exposed workers not just those in the near area应该全面照顾到所有可能进入污染区域的工人，而不是只考
24、虑几个直接参与者Maintenance of PPE is a priority if the expected level of protection is to be achieved.要达到预期的防护效果，就必须把个人防护用具的维护放在第一位,Ventilation in a Laboratory Sample Room实验室样品间的排风系统,Following complaints from laboratory technicians working in a sample preparation room regarding high levels of noise and dus
25、t, an inspection was undertaken by an occupational hygienist在收到一些在实验室样品间工作的技术人员的关于高度噪音和灰尘的投诉后，某职业卫生专家开展了一次检查Upon attendance, the occupational hygienist found the ventilation system to be somewhat of a “jigsaw puzzle” in that there were numerous branches off a main duct leading to grinding mills and
26、furnaces all connected to the one fan 专家在现场发现样品间的排风系统就像一副“拼图玩具”，一个通向研磨机和火炉的主管道又分出数个分管道，而所有的管道都同时使用同一个风扇,Ventilation Ductwork Connected to Fan与风扇相连的排风管道系统,Source: University of Wollongong,Homemade Extraction System自制的抽风系统,Source: University of Wollongong,Inappropriate Duct Design不当的管道设计,Source: Unive
27、rsity of Wollongong,Inappropriate Duct Design (cont)不当的管道设计(续),Source: University of Wollongong,Inspection of Ventilation System排风系统检查结果,Homemade ventilation system with numerous braches and poor duct design自制的通风系统附带了数个分通风管，并且设计粗糙Only one fan installed for total system and in poor condition整个系统只安装了一
28、个风扇，而且装得很不好Fan capacity not matched to system requirement风扇鼓风量与系统要求不相适应No balancing of system ever undertaken从未进行过管道的系统分配,Performance Measurements通风系统的性能测评,Some tube and air velocity measurements confirmed that air was traversing duct closest to fan and little airflow in other branches对管道和风速的进行的一些测评
29、再次确认，气流能穿过那根离风扇最近的管道，但其它分支管道几乎没有气流No maintenance or system performance records could be found找不到任何对排风系统性能的养护记录,Additions to System over Time排风系统日积月累的扩张,Apparent that as the laboratory had expanded, the ventilation system had been extended without due consideration of the size of the fan, duct design
30、 or the extensive duct branching很明显，随着实验室的扩大，其排风系统也随之膨胀，但从没有人正确思考过风扇功率、管道设计或过多的管道分流等问题Unfortunately, the situation above is not uncommon and serves to highlight that any ventilation system should be fit for purpose and simply adding another branch can upset the whole system不幸的是，上述情况并不罕见。它有力地证明：任何排风系
31、统都应该切合使用对象；简单增加分支管道会影响整个系统。,Key Learnings重要经验,Ventilation systems need to be designed to meet the individual process needs在设计排风系统时需要切合具体的生产需求Implementation of a ventilation system is not the end of the exercise. Good maintenance practices need to be observed通风系统投入使用并非是最终的结果，还需要注意对其进行良好的养护System perf
32、ormance needs to be regularly monitored应该定期监测通风系统的综合性能,Mercury Exposure in a Gold Room炼金室内水银污染,The final stage of extracting gold from ore using the carboninpulp method is to smelt the recovered elemental gold so as to remove impurities 从金矿石萃金的最后工序需要用到含碳矿浆法来提炼回收的黄金元素才能去除杂质The smelting process involv
33、es heating the raw gold in a natural gas furnace and creating a slag on the surface of the molten gold using various minerals提炼过程包括用天然气炉加热生金，并用各种矿物使得熔化的黄金表面形成熔渣,Treatment of Impurities杂质的处理,Many impurities transfer from the gold to the slag under controlled metallurgical conditions but others (eg:me
34、rcury) are released to the atmosphere as a vapour.很多杂质在冶金工艺的控制下从金矿石中分离出来转化成熔渣，但有些杂质（如水银）却是蒸发到空气中At the appropriate time the gold is poured, cooled, identified and sent to a specialist refinery for further processing黄金会在适当的时间被倾倒，冷却，鉴定，然后送往专业的精炼厂进一步加工,Gold Pour倾倒黄金,Source: University of Wollongong,Cur
35、rent Control Measures目前的控制措施,The furnace is located under a canopy type hood which is linked to an extraction fan outside the building. The purpose of an extraction system is threefold熔炉被置于一个伞形罩下，这个伞形罩与户外的一扇排风扇相连。其目的有三：To remove any combustion gases 排除所有燃烧废气To remove any contaminants 排除所有污染物To remov
36、e hot air 排除热空气,The Issue问 题,Following complaints from workers an examination of the gold room was undertaken炼金工人的投诉招致了对炼金车间的检查Initial findings were that there were elevated levels of mercury present in the atmosphere (albeit below the exposure standard), capture velocities of the canopy hood were l
37、ow and that there was minimal air movement within the gold room初步的检查结果是，室内空气中水银的含量越来越高（尽管尚未达到污染标准），伞形排风罩的抽风速度低下，导致了炼金车间内的空气流动不畅,Ventilation System排风系统,Examination of the fan established that the belts between the drive motor and the fan impeller shaft were continually “slipping”, thus decreasing the
38、 degree of extraction 对排风扇的检查发现，连接驱动马达与叶轮轴的传动带越来越“疲软”，从而导致抽风速度减慢。Closer examination of the outer fan housing and ductwork found significant openings due to corrosion (the fan was not protected in the harsh equatorial climate) again reducing the efficiency of the system对外部风扇罩和管道系统进一步检查后，发现了由于腐蚀产生的开口（
39、排风扇在酷热的赤道气候下没有得到保护）进一步减弱了排风效果,Actions Taken to Address Issues针对问题采取的措施,Repairs were made to the ventilation system with a resultant improvement in capture velocities 维修提高了排风系统的排风速度Mercury levels were no longer detected, and while the airflow in the gold room increased it was not at a level that was
40、expected 室内再没有探测到空气中存在水银，炼金室的气流增加的同时，水银的浓度就降低到比预想还要低的程度Inspection of air intake vents for the air supply system established that many were blocked, thus limiting the amount of makeup air entering the gold room. Once these were cleared, air movement within the gold room increased通过检查系统风源的进风口证明许多进风口都堵
41、住了，因此限制了对炼金室的进风补充。进风口一经清理，炼金室内的空气流动就增加了,Key Learnings重要经验,The process itself may produce contaminants that require control (e.g. mercury)生产本身就可能产生污染，而污染物（如水银）需要加以控制All ventilation systems are prone to failure if not adequately maintained所有的排风系统在得不到良好维护的情况下都会失效A simple check of the hood face velocity
42、 or the hood static pressure would have highlighted the ventilation system issues其实只要对伞形罩的表面风速或者罩内静态压力进行简单的检查，就能找到问题的主要根源所在乃是通风系统出了问题,Manufacture of Phthalic Anhydride生产邻苯二甲酸酐,Phthalic anhydride is an important bulk chemical and is used in the manufacture of phthalate ester plasticisers, polyester f
43、ormulations for boat hulls, glass reinforced plastic applications and in alkyd resins for paints邻苯二甲酸酐是一种重要的散装化学用品，可用来制造酞酸酯增塑剂、船体聚酯配方、玻璃钢和涂料用醇酸树脂,Production Process生产过程,Over 85% of commercial phthalic anhydride is produced from oxylene by gas phase oxidation using vanadium pentoxide as a catalyst 85
44、%以上的工业邻苯二甲酸酐都是用气相氧化法，以五氧化二钒作催化剂，从邻二甲苯中生产出来的。The final product is sold in bulk bags of 500kg or 1,000kg capacity, road tanker and 25kg bags as a flaked solid. The product is also sold in the molten form and transported in insulated road tankers其成品被装在500公斤或1000公斤容量的集装袋、公路油罐车和25公斤的口袋中以粉末状固体形态销售。也以熔液形态销
45、售，并用绝缘油罐车运输。,Properties & Health Effects属性和对健康的影响,White solid at room temperature 在室温下呈白色固体Melting point of 131C 熔点:摄氏131度Saturated vapour pressure of 1mm Hg 96.5C饱和蒸汽压摄氏96.5度时为1 毫米汞柱Phthalic anhydride is a known respiratory sensitiser with established workplace exposure limits.邻苯二甲酸酐是一种已知的可吸入感光剂，为限
46、制其对生产场所的污染相关标准已经成型,Workplace Situation工作现场环境,Concern was raised as to the potential exposure of workers during the filling of bulk bags with phthalic anhydride immediately after manufacture工人在产品刚生产出来以后就装袋的过程中与邻苯二甲酸酐的身体接触问题就引发了担心,Initial Survey by Occupational Hygienist职业卫生专家的初步调查内容,24 hour productio
47、n process 24小时作业过程Flaked solid main area of potential exposures粉末状固体主要的潜在污染场所Re-handing of processed product due to quality issues对因质量问题处理过的产品进行的二次装卸LEV system limited & subject to failureLEV体系作用受限并且失效,Initial Survey (cont) 初步调查内容（续）,LEV system not designed for capture & transport of phthalic anhydr
48、ide & fume局部排气通风体系没有根据邻苯二甲酸酐的运输保存方式和有害气体的管理来设计Bulk bag system designed for 1000kg bags but used for 500kg bags集装袋设计为1000公斤装，但实际运用却只装500公斤Increased exposure due to need for manual connection, disconnection & tie-off of bags手工对集装袋连接、断开和封口延长了工人与有害物质的接触时间All workers complying with PPE standards 所有工人都穿戴了
49、防护用具,Preliminary Monitoring 初步监察,Monitoring indicated that long term exposures ranged up to a maximum of 4.1mg/m3 phthalic anhydride during bag filling operations. 监察结果显示，在装袋的操作环节物料长时间的暴露在空气中能产生最高4.1mg/m3 浓度的含邻苯二甲酸酐的有害空气As the statutory exposure limit was 4.0 mg/m3 appropriate action was required to reduce employee exposures.法定的污染标准是4.0 mg/m3 。必须采取得当的措施缩短工人与有毒物料的接触时间,
