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对稀硝装置氧化工艺氨-空比值控制系统的2种控制方案——流量控制方案和比值控制方案分别作了介绍。比较了2种控制方案在参数显示、运行操作方式和系统性能上的差异,比值控制方案较流量控制方案略胜一筹。 相似文献
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气田开发方案(新区开发方案、老区调整方案)关系到企业经济效益。方案设计包括技术和经济两部分。技术方案从技术的角度提出了部署内容、需采用的技术及开发指标预测,并规定出所达到的工作量投入,保证了方案的技术可行性。但是由于方案设计的多选择性,要保证方案在经济上最优。本文以台吉气田推荐方案为例,研究气田开发方案经济评价,对方案进行经济评价和方案优选,为气田合理开发决策提供科学依据。 相似文献
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直接法合成的苯基氯硅烷粗单体是一种成分复杂的多组分混合物,其分离纯化较为困难,国内外鲜有报道。文中设计了4种分离方案并与文献中已有的分离方法进行对比。利用Aspen Plus对以上5种分离方案进行严格模拟计算,旨在保证一苯基三氯硅烷、二苯基二氯硅烷的纯度及收率的前提下找出年度费用最低的分离方案。基于易分离度系数法的分离方案年度总费用最低,比现有分离方案的年度总费用降低了7.8%。以该流程为初始方案,利用调优法找出4组相邻分离方案。通过对4组分离方案进行精确模拟计算,得到结论:调优方案3年度总费用最低,为苯基氯硅烷单体分离的最优分离方案,比初始方案年度总费用低了3.5%。 相似文献
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对化工工业中精馏塔经典的塔釜温度控制方案及其凝结水回收系统进行了深入的研究。结合实际生产情况,对典型的三种控制方案进行深入的讨论与分析,强调说明了每一种方案的适用场合、安装要求。对三种控制方案的优缺点进行了归纳说明,并提出了相应的优化方案。 相似文献
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对LDPE装置低压分离器加料的方案进行了分析,指出了常规加料方案存在的不足。针对大庆石化20万t/a高压聚乙烯装置的挤压系统实物料试车,提出了一套新的加料方案,并对该方案进行了理论计算。实践证明,通过辅助挤压机加料的方案可行,并解决了常规加料过程中存在的不足,为系统的顺利试车提供了可靠保证和理论依据。 相似文献
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清洁生产是制药企业未来发展的必由之路。对制药行业清洁生产进行案例分析,阐述了从审核、方案的产生和筛选、方案确定,到方案实施等环节,最后分析了方案的实施为企业带来的环境效益。 相似文献
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少烟三元乙丙橡胶材料研制 总被引:1,自引:0,他引:1
以三元乙丙橡胶(EPDM)为基体材料,三氧化二锑、十溴苯醚为阻燃剂制备了材料配方,试验了三氧化二锑(Sb22O3)、十溴苯醚(DBDPO))配比对材料烟雾和力学性能的影响,测试了材料的氧指数,可见光的透过率,自熄性等。结果表明,DBDPO与EPDM的相容性比较好,Sb2O3的相容性则相对比较差,两者都可以提高材料的阻燃性能。以4045EPDM橡胶为基体材料,当EPDM100g,白炭黑10g,二硫化四甲基秋兰姆(TMTD)2g,ZnO5g,促进剂M1g,硬脂酸2g,硫磺3g,Sb2O3和DBDPO质量比为20.0/40.0,可以获得具有较好力学性能的少烟EPDM橡胶材料。 相似文献
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国内甲醇消费市场状况 总被引:1,自引:0,他引:1
黄克勇 《精细与专用化学品》2005,13(5):23-27
我国甲醇主要用于甲醛、对苯二甲酸二甲酯、农药、甲基叔丁基醚、醋酸的生产,我国甲醇消费量增长最快的领域将是燃料甲醇、醋酸和甲醛。预计 2005年甲醛对甲醇的需求量为 175万t左右,聚甲醛对甲醇的需求量为 40万t,醋酸需求甲醇为 62万t,甲基叔丁基醚为 46万t左右,甲胺为 30万t,碳酸二甲酯为 11万t,甲烷氯化物为 10万t,甲醇燃料为 80万t,农药为 22万t,对苯二甲酸二甲酯 3 0万t,其他衍生物 27万t。 相似文献
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Hamed Abbasfard Sattar Ghader Hasan Hashemipour Rafsanjani Mehdi Ghanbari 《Drying Technology》2013,31(11):1297-1306
Drying of ammonium nitrate (AN) is accomplished in the Shiraz Petrochemical Complex (SPC) using a concurrent rotary dryer following a countercurrent rotary dryer. A mathematical model for these rotary dryers including heat and mass transfer was developed. The model was checked against industrial-scale data, which showed a good agreement. The average absolute deviation of the simulation results compared to the industrial data for the concurrent dryer was 4.0% for solids moisture, 1.3% for solids temperature, and 1.8% for air temperature and for the countercurrent dryer it was 9.0% for the solids moisture, 2.0% for solids temperature, and 4.6% for air temperature. These simulation results reveal that for outlet solid moisture, inlet AN moisture, and air temperature as well as the outlet temperature of product, the inlet solid and air temperature have major effects for both concurrent and countercurrent flow. 相似文献
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汽车工业用粘接材料的现状与展望 总被引:3,自引:0,他引:3
本文按照汽车制造工序介绍国外汽车工业折边用胶粘剂、点焊胶接用胶粘剂、车身密封胶、车身底涂料、窗玻璃用单组份湿气固化型聚氨酯胶粘剂以及纤维增强树脂用结构胶粘剂等主要胶种的最新技术发展动向。讨论了我国汽车工业用胶粘剂的现状和差距,提出几点建议。 相似文献
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采用DUO-ICP-AES同时测定精对苯二甲酸中钴、铬、铁、锰、钼、镍、钛,并对仪器的分析线选择、背景校正、入射功率、雾化器压力、辅助气流量、冷却气流量、蠕动泵转速的影响及共存元素的干扰、硝酸铯灰化助剂等因素进行了详细的研究。方法的检测限:钴0.0097 mg/L;铬0.0021 mg/L;铁0.0078 mg/L;锰0.0012 mg/L;钼0.0027 mg/L;镍0.016 mg/L;钛0.0027 mg/L,回收率和精密度分别为93.0%~99.5%和0.37%~3.2%。该方法快速简便,具有良好的精密度和准确度,适用于进出口精对苯二甲酸的日常检验。 相似文献
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The article presents the results of studies concerning the hydraulic permeability of integrated membrane systems during the treatment of municipal landfill leachate. The laboratory-scale experiments were conducted to determine the effectiveness of coagulation as a pretreatment option for treating stabilized landfill leachate and effectiveness of nanofiltration (NF) and reverse osmosis (RO) processes. The municipal landfill leachates were analyzed for the concentration of the following: polycyclic aromatic hydrocarbons (PAHs), nitrate nitrogen, ammonium nitrogen, chemical oxygen demand (COD), total organic carbon (TOC), total carbon (TC), suspended soils (SS), turbidity, pH. The commercially available coagulant – aluminum sulfate Al2(SO4)3·18H2O (alum) was used as a coagulant. The NF process was carried out at the transmembrane pressure of 1.5 MPa. The membrane separation process was based on a thin film membrane (DK). The transmembrane pressure of the RO stood at 2 MPa and for this process one polyamide membrane (AG) was used. The level of leachate treatment was defined for raw and cleaned wastewater indicators. Both NF and RO membranes allowed obtaining the high level of pollutants removal. In the coagulation–NF system, the removal efficiency was equal to 77% for PAHs, 88% for COD, 72% for ammonium nitrogen, 80% for nitrate nitrogen, 67% for TOC, 80% for TC, 96% for SS and during the RO – 86% for PAHs, 98% for COD, 93% for ammonium nitrogen, 87% for nitrate nitrogen, 89% for TOC, 100% for TC, 98% for SS. The calculations based on the assumptions of the mathematical filtration model (relaxation) made it possible to predict the efficiency of commercial filtration membranes used for leachate treatment. 相似文献
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Hendrik R. Sikkema Bauke F. Gaastra Tjeerd Pols Bert Poolman 《Chembiochem : a European journal of chemical biology》2019,20(20):2581-2592
We are aiming for a blue print for synthesizing (moderately complex) subcellular systems from molecular components and ultimately for constructing life. However, without comprehensive instructions and design principles, we rely on simple reaction routes to operate the essential functions of life. The first forms of synthetic life will not make every building block for polymers de novo according to complex pathways, rather they will be fed with amino acids, fatty acids and nucleotides. Controlled energy supply is crucial for any synthetic cell, no matter how complex. Herein, we describe the simplest pathways for the efficient generation of ATP and electrochemical ion gradients. We have estimated the demand for ATP by polymer synthesis and maintenance processes in small cell-like systems, and we describe circuits to control the need for ATP. We also present fluorescence-based sensors for pH, ionic strength, excluded volume, ATP/ADP, and viscosity, which allow the major physicochemical conditions inside cells to be monitored and tuned. 相似文献
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Sang Hoon Ahn Seung Nam Joung Ki-Pung Yoo Min Jeong Noh Joo Hee Han Seung Ho Han 《Korean Journal of Chemical Engineering》1998,15(4):390-395
Supercritical water oxidation (SCWO) was carried out in a flow-type reactor for modeling of waste-water containing phthalic
or adipic acid. For each acid, the reaction order and rate constant, k, were determined over a wide range of experimental
conditions : temperatures from 633.15 to 713.15 K, pressures from 18 to 29 MPa, excess amounts of hydrogen peroxide from zero
to 800 percent, and the mean residence time in the reactor from 1.1 to 49.1 seconds. The concentration of both acids in model
wastewater was set by 500 ppm. For phthalic acid, we found that the orders of decomposition reaction with respect to the reactant
concentrations were 0.56 for phthalic acid, 0.31 for hydrogen peroxide, and 0.53 for water. For adipic acid, the orders of
oxidation were 0.78 for adipic acid, 0.53 for hydrogen peroxide, and 0.74 for water. Then measured activation energy for phthalic
acid was 33.08 kcal/mol and that for adipic acid was 19.51 kcal/mol, respectively. 相似文献
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M. D. A. Bolland 《Nutrient Cycling in Agroecosystems》1994,38(1):29-45
The effectiveness of coastal superphosphate, a partially acidulated rock phosphate (PARP) made from apatite, and Ecophos, a PARP made from calcium iron aluminium (crandallite millisite) rock phosphate, was compared in pot experiments with the effectiveness of ordinary superphosphate (OSP) and North Carolina reactive apatite rock phosphate (NCRP). There were three experiments using different lateritic soils collected in Western Australia. Fertilizer effectiveness was measured using yield of dried wheat (Triticum aestivum) tops grown for 28 days. Three successive crops were grown. The phosphorous (P) fertilizers were applied and mixed with the soils before sowing the first crop. In addition, OSP was added to extra pots before sowing crops 2 and 3 in order to measure the effectiveness of the original P fertilizers relative to freshly-applied OSP for these crops.As measured using plant yield, coastal superphosphate was the most effective P fertilizer for three crops on an acidic peaty sand (pH water 5.0). Relative to freshly-applied OSP, it was 154% as effective for crop 1, 75% as effective for crop 2, and 36% as effective for crop 3. Corresponding values for Ecophos were 44, 29 and 19%, and for NCRP, 77, 67 and 29%, with the original OSP treatment being 61 and 56% as effective for crops 2 and 3. For three crops on a lateritic gravel loam (pH 6.5), both coastal superphosphate and OSP were the most effective fertilizers, and were equally effective for crop 1, and relative to freshly-applied OSP, were about 31% as effective for crop 2, and 16 and 21 % as effective for crop 3. Corresponding values for Ecophos were 47,15 and 11%, and NCRP, 33,15 and 5%. For two crops in a loamy sand (pH 5.4), OSP was the most effective fertilizer, and, relative to fresh OSP, it was 36% as effective for crop 2. Relative to fresh OSP, the effectiveness for crops 1 and 2 of coastal superphosphate was 57 and 18%, for Ecophos 71 and 27%, and for NCRP 50 and 36%. 相似文献