化工过程安全2008 A答案.doc

姓名 学号 学院 专业 座位号 ( 密 封 线 内 不 答 题 )密封线线_ _ 诚信应考,考试作弊将带来严重后果！ 华南理工大学期末考试化工过程安全工程试卷A 注意事项：1. 考前请将密封线内填写清楚； 2. 所有答案请直接答在试卷上(或答题纸上)； 3考试形式：闭卷； 4. 本试卷共 四 大题，满分100分，考试时间120分钟。题 号一二三四五总分得 分评卷人一 一、判断题 (每题2分, 共20分)1、 单一同系物闪点闪点随相对分子质量的增大、沸点的降低、相对密度的增大而升高。（ F ）2、 反应级数的大小表示浓度对反应速率影响的程度，级数越大，则速率受浓度影响越小。（ F ）3、 明火设备应集中布置在装置的边缘，应远离可燃气体和易燃、易爆物质的生产设备及储槽，并应布置在这类设备的下风向。（ F ）4、 闪点28的液体的火灾危险性分为甲类。（ F ）5、 乙醇、乙醚混合液体中加入杂质水，会极大地降低液体的闪点，使液体的燃烧爆炸性危险显著增加。（ F ）6、 利用甲醚作为蒸汽锅炉的燃料，此时锅炉房的火灾危险性为甲类。（ F ）7、 甲、乙、丙类仓库内严禁设置办公室、休息室等，并不应贴邻建造。（ F ）8、 泄压设施宜采用轻质屋面板、轻质墙体和易于泄压的门、窗、玻璃等。（ F ）9、 工厂消防用水量应为发生最大可能的火灾时的灭火用水量。（ F ）10、 防火间距计算方法是从建筑物外墙凸出部分算起；铁路的防火间距，是从邻近一边的路边算起；公路的防火间距是从道路中心线算起。（ F ）二、选择题 (有一项以上是正确的，每题3分, 共30分)1、乙醇属于（ ）危险化学品。 A甲类 B乙类 C丙类2、锅炉的三大安全附件分别是安全阀、（ ）与水位表。 A电表 B温度计 C压力表3、在化工厂中比较容易形成爆炸性气体环境。根据爆炸和火灾危险环境电力装置设计规范（GB50058-1992），对于生产、加工、处理、转运或贮存过程中出现或可能出现下列( )之一时，应进行爆炸性气体环境的电力设计。A在大气条件下，易燃气体、易燃液体的蒸气或薄雾等易燃物质与空气混合形成爆炸性气体混合物；B闪点低于环境温度的可燃液体的蒸气或薄雾与空气混合形成爆炸性气体混合物；C闪点等于环境温度的可燃液体的蒸气或薄雾与空气混合形成爆炸性气体混合物；4、甲、乙类生产（ ）设在建筑物的地下室或半地下室内。 A不宜 B不应 C可以5、甲醇溶液的火灾危险性分类的依据是（ ） 。 A闪点 B爆炸浓度极限 C物质系数6、（ ）类的液体仓库应设置防止液体流散的设施。 A 甲 B. 乙 C. 丙 D. 丁7、低闪点液体的闪点是（ ）。A、小于15 B、小于18 C、小于23 D、小于288、室外消火栓的间距不应大于（ ）米。 A、90 B、100 C、110 D、1209、爆炸性混合物的（ ）能影响爆炸极限范围。 A、温度 B、压力 C、含氧量 D、火源能量10、危险化学品的贮存方式有（ ） A、单个贮存 B、隔离贮存 C、隔开贮存 D、分离贮存A BC ABC B A ABC B D ABCD BCD三、Short Answer Questions(20 points ,10 points each)1. what are the inherent safer design strategy during the stage of process research. to use the non-combustible materials to replace the combustible mass; to Replaces virulent or the high poisonous material with non-toxic either the low poisonous material; to uses the low corrosive material. to use the new craft route to avoid danger raw material or the intermediary product; to uses the catalyst or a more effective catalyst; to reduced side reaction harm to depressurize with the temperature；to reduces the reaction medium density2.Analyze the possible measures that can be taken to control the chemical process material safety. Substitution or controling the amount Strengthen airtight Vented exhaust Deactivation Gas strength monitoring and warning Specialized material processing四、 Essay Questions (30 points ,15 points each)1.A plant was doing a pneumatic pressure test on a pipe connected to a tank. There was no blind flange between the piping being tested and the tank. The tank was isolated from the pressurized piping with a closed block valve. The block valve leaked, allowing the pressure from the pneumatic test to leak into the tank. The tank (which either did not have a pressure relief device installed, or the pressure relief device was too small) was overpressured, and it failed at the bottom. The tank lifted into the air and came to rest on the top of the plant. Please analyze the safety problems during the pressurization pressure operations and discussion on the corresponding countermeasures and measures. During pressure tests, or any other maintenance or non-routine activities involving pressure, make sure that all equipment is capable of withstanding the test pressure, is positively isolated from the source of pressure, or has adequately sized pressure relief devices for the testing conditions. Equipment can be protected from being overpressured more reliably by using blinds, or byphysically disconnecting piping, rather than using valves to isolate the equipment from pressure. Do a process safety review before starting any non-routine operations to identify potential hazards and required safeguards during the operation. Keep workers away from the area where pressure testing operations are being conducted. If possible, pressure test lines using liquid pressure (hydrostatic pressure) rather than pneumatic (gas) pressure - the energy which can be released from a liquid overpressure is MUCH LESS than from a gas overpressure.2. Heres what happened. In Fig.(a), when steam cleaning the interior of a railcar most of the air was displaced. When work was stopped at the end of the day all valves were closed. As the car cooled, the steam condensed, creating a vacuum, causing the railcar to collapseIn Fig.(b), During painting, a tanks vacuum relief valve was covered with plastic to prevent potential contamination of the contents. When liquid was pumped out the plastic covering prevented air/nitrogen from replacing the liquid volume. A vacuum developed leading to the partial collapse of the tank. (a) (b)a.Please analyze the COMMON causes of vacuum damage to tanks .b. What is the measures to prevent equipment damage from vacuum?ANSWERa.COMMON causes of vacuum damage to tanks include: The vessel has insufficient strength to withstand a vacuum; a vessel with a higher pressure rating is frequently capable of withstanding a full vacuum; vacuum is created when liquid is transferred from a vessel or when hot vapor condenses, neither of which is replaced by air/nitrogen or other non-condensable material. a vacuum relief system is not present or is not functioning properly.b.Things to consider to prevent equipment damage from vacuum: install a system to provide vacuum relief. As one of the pictures graphically demonstrates, railcars and trucks MAY NOT have this equipment. These devices will allow air to enter the vessel and prevent vacuum formation. if installed, vacuum relief devices must be inspected and tested on a regular basis. They are just as critical as pressure relief devices. understand which vessels in your department are not rated for full vacu