Demand response potential of industrial processes considering uncertain short-term electricity prices

Time-varying electricity prices on the day-ahead and intraday market incentivize demand response of industrial processes. In prior work (Schäfer et al. AIChE J. 2020;66:1-14), we studied the demand response potential with a generalized process model, but neglected the intraday market. Extending our prior investigation, we account for uncertain intraday prices in a mixed-integer linear stochastic programming-based scheduling, that is, we minimize expected cost and conditional value-at-risk in a bi-objective optimization. We find that for very broad variations of the generalized process parameters, the conditional value-at-risk can be reduced significantly without drastically increasing the expected cost. Furthermore, simultaneously improving multiple process parameter leads to synergetic benefits. Moreover, the savings of three electrolysis processes can be more than doubled by marketing flexibility on the intraday market in addition to the day-ahead market. Overall, our model allows for a rapid early assessment of the demand response potential considering the two markets.     

Energy demand management for process systems through production scheduling and control

Demand response (DR) is an integral part of the Smart Grid paradigm, and has become the focus of growing research, development, and deployment in residential, commercial and industrial systems over the last few years. In process systems, energy demand management through production scheduling is an increasingly important tool that has the potential to provide significant economic and operational benefits by promoting the responsiveness of the process operation and its interactions with the utility providers. However, the dynamic behavior of the underlying process, especially during process transitions, is seldom taken into account as part of the DR problem formulation. Furthermore, the incorporation of energy constraints related to electricity pricing and energy resource availability presents an additional challenge. The goal of this study is to present a novel optimization formulation for energy demand management in process systems that accounts explicitly for transition behaviors and costs, subject to time‐sensitive electricity prices and uncertainties in renewable energy resources. The proposed formulation brings together production scheduling and closed‐loop control, and is realized through a real‐time or receding‐horizon optimization framework depending on the underlying operational scenarios. The dynamic formulation is cast as a mixed‐integer nonlinear programming problem based on a proposed discretization approach, and its merits are demonstrated using a simulated continuous stirred tank reactor where the energy required is assumed to be roughly proportional to the material flow. © 2015 American Institute of Chemical Engineers AIChE J, 61: 3756–3769, 2015     

响应曲面法优化硫酸铵微波干燥工艺

对微波干燥硫酸铵的新工艺进行研究,探讨了干燥温度、微波干燥时间、物料质量、物料厚度等因素对硫酸铵相对脱水率的影响.并在单因素实验的基础上,以硫酸铵的相对脱水率为响应值采用响应曲面中心组合设计,对硫酸铵的微波干燥工艺参数进行了优化.所获得的优化实验条件:干燥温度86.05℃,微波干燥时间190.50 s,物料质量102....     

氨水配制器在硫磺制酸尾气氨法脱硫中的应用

介绍了威顿(中国)达州化工有限责任公司改造后氨水配制的工艺流程和操作方法。改造后,氨水配制过程中氨水槽温度较原工艺降低,内部气压较低,不会发生氨水槽液封被冲破、大量氨逃逸至脱硫塔的现象;中控室远程控制配制氨水,操作人员不用现场操作,避免了因液氨泄漏造成人员伤害事故的发生。     

管壳式自热型氨分解反应器模拟分析

建立了管壳式自热型氨分解反应器,其中管内为拟均相催化反应,管外壳程为考虑气膜传递阻力的非均相催化反应。通过模拟比较和分析了氨气和氢气-空气混合物并流与逆流操作的反应结果。在并流操作中,氢燃烧产生的高温正好与高氨气浓度对应,氢燃烧热被充分用于氨分解反应,因此反应效率要显著高于逆流操作。与等温反应器的比较分析表明,在自热和高转化率条件下并流操作的效率与等温操作效果很接近。     

低碳混合醇技术和中小型氨厂产品转向

本文介绍低碳混合醇应用现状及国内应用前景．对四种合成工艺进行了简评，结合国内中小型氨厂特点，提出了工业化建议。     

Electrochemical removal of ammonia,chemical oxygen demand and energy consumption from aquaculture waters containing different marine algal species

Phytoplankton over‐blooming and consequent die‐off is one of the major contributory factors for ammonia and chemical oxygen demand (COD) loadings. In this work, electrolysis technology was applied to determine its ability to remove ammonia and total chemical oxygen demand (TCOD) in both laboratory‐scale batch and continuous systems. Under an initially set voltage of 5 V, a constant current of 0.1 A was applied and different retention times were used for ammonia‐removal experiments. Results showed that these conditions are not satisfactory in removing TCOD loadings contributed by algal cells. However, a retention time of 35.7 min was sufficient to remove 100% ammonia from algal‐uncontaminated waters. Ammonia removals in waters containing Chlorella spp and Isochrysis spp were 87 and 68%, respectively, after 140 min of electrolysis. Energy consumption for ammonia removal in algal‐free water was 50 W mg^?1 of ammonia. For waters containing Chlorella spp and Isochrysis spp energy consumptions were 67 and 85 W mg^?1 of ammonia, respectively. Interestingly, the applied mild electrolysis condition was just sufficient to control excess algal blooming and ammonia without increasing the dissolved COD and chlorine in shrimp grow‐out ponds. This minimizes operating costs due the process requiring less energy. Furthermore, it was also found that electrolysis does not lower alkalinity. Copyright © 2005 Society of Chemical Industry     

氯化亚砜产需现状及发展建议

介绍了国内氯化亚砜的生产,应用概况及国内市场需求状况,并对今后氯化亚砜的生产与应用提出了建议。     

Kinetic studies of removal of ammonia from seawater by ozonation

A simplified mathematical model for the estimation of the rate of removal of ammonia during the ozonation of seawater was developed, considering the kinetics of the interactions between ozone and both the chloride and bromide ions in seawater during oxidant formation and oxidation of ammonia. The model also considered effects of the rate of ozone mass transfer and the pH. The rates of removal of ammonia in the pH range between 6.5 and 9.0 coincided well with the values estimated by this model. It was also shown that stripping of ammonia during air/ozone treatment considerably affected the rate of removal of ammonia when the pH was higher than 8.5. The chloride ion, which is the dominant ion in seawater, showed a negligible contribution to the oxidation of ammonia during ozonation. The formation of BrO₃^?, classified as a carcinogen did not occur as long as ammonia was still present. © 2002 Society of Chemical Industry     

炼焦剩余氨水蒸氨工艺的改造

分析了蒸氨工艺中换热器废水通道堵塞的原因,提出了在蒸氨塔和换热器之间安装旋液分离器的方案,有效地降低了废水中固体杂质的含量。同时,通过定期对氨水槽和混匀器底部放油,降低了氨水中的含油量,有效地解决了换热器废水通道堵塞的问题。蒸氨废水的合格率全年保持在98%以上,真正发挥了蒸氨装置的环保回收作用。     

α-烯烃的需求和生产技术

本文介绍了国内外α-烯烃的需求量和生产技术，以及我国目前α-烯烃的生产能力和状况。     

中型合成氨厂的技术改造探讨

本文对我国以煤为原料的中型合成氨厂的技术改造进行较为深入的讨论。同时对“油改煤”中氮厂的技术改造提出了一些看法和建议。     

我国塑料的生产与需求

我国塑料工业的发展较快,1991年生产能力达394万t,产量达284万t,1980～1991年平均年增长率为11%;我国塑料的消费量不断增长,1991年消耗量为381万t;预计,1995年的消耗量可达465万t,产量将达425万t。     

含氨尾气的氨吸附研究

在模拟含氨尾气组成的条件下,研究了复合吸附剂对氨的吸附。结果表明,常压下复合吸附剂的纯氨吸附量达到0.25 g/g;以氮气作为载气时,对氨吸附量影响很小;水蒸气的存在对复合吸附剂的氨吸附量影响较大;在较低温度、较高氨分压时,复合吸附剂对氨具有较好的吸附效果。复合吸附剂的吸附稳定性好、吸附量高,吸附法是一种很有前景的处理含氨尾气的方法。     

Pt-Ir共沉积电位对电解氨水制氢的性能影响

为研究在线电解氨水为氢燃料电池供氢的可行性,采用电化学共沉积法,在不同沉积条件下制备了PtIr催化电极,用循环伏安法(CV)与计时安培法(I-t)结合电镜、XPS和XRD结构分析,研究了电极对氨水的电解催化性能。结果表明,沉积电位影响了合金催化剂的组成、晶型、晶粒尺寸等,从而进一步影响了电极在氨催化过程中的性能。当沉积电位固定,电极上的催化剂负载量、氨水电解过程中催化剂的形貌、结构、组成基本稳定。其中,-0.05 V(vs. SCE)沉积电位下制备的催化剂在氨的电解催化过程中持续性和稳定性好,催化剂的负载量和过电位也最低。利用电化学上电解氨和生成水电位上的差异,将氨电解为燃料电池供氢,在低电流密度下(<10 mA/cm²)燃料电池为氨电解池提供能量的同时仍然有40%以上的额外功率用于其他负载。     

钡离子对镍基钙钛矿分解氨的影响

镍基钙钛矿分解氨制取氢气虽有稳定性好、价格低廉的优点,但也有完全分解温度偏高的缺点。为降低完全分解氨制取氢气的温度,实验采用柠檬酸络合法,通过改变A位掺杂离子与掺杂量对LaNiO₃改性,并改变载体及负载量,制备一系列的催化剂。采用XRD、SEM、TEM表征技术进行表征,考察了Ba 含量对催化剂结构与性能的影响。实验表明在催化剂装填量为1mL、空速为10000h^-1、原料气为纯氨的条件下,氨分解的最佳电子助剂离子为Ba、最优催化剂为w(NiO)=20%的La_0.9Ba_0.1NiO₃/MCM-41,氨气完全分解温度由650℃降为575℃。随着Ba掺杂量的增加,催化剂活性先增加,在x=0.1达到最大值,之后减小,掺杂Ba过多催化剂的结构由钙钛矿变为非钙钛矿,非钙钛矿结构的催化剂活性不如钙钛矿。     

我国乙二醇的生产与需求

我国近年来乙二醇生产发展迅速，但仍满足不了国内迅速增长的需求．１９９４年我国乙二醇的产量达３８．９９万ｔ，需求量为５１．３３万ｔ。预计１９９６年国内总需求量约为６０万ｔ。     

纯碱的生产与需求

1992年我国纯碱的产量达455万t,比1991年增长15.6%,居世界第二位,消费突破400万t,比上年增长10.6%,预计1994年需求量为450万t。我国纯碱的出口量大幅度增长,进口量不断下降,1992年进口1.68万t,出口37.52万t;1989年世界纯碱的生产能力达到3863万t,比上年增长了6.5%,产量达到3191万t,比上年增长了3%。     

氨水配制系统改造实践

介绍了威顿(中国)达州化工有限责任公司氨法尾气脱硫系统中氨水配制过程的改进情况。分析了现有氨水槽配制氨水存在的问题,利用管道混合器、冷却器和调节阀等,将氨水配制由人工操作改为自动控制,既提高了工作效率,降低了劳动强度,又提高了氨水配制的安全性。     

我国硫酸产需现状与展望

由于与磷肥及化工配套的硫磺制酸的大力发展以及有色金属市场好转带动的冶炼烟气制酸的迅速发展,到2005年我国已形成硫酸生产能力55 500 kt/a,产量46 250 kt,同比增长15．8％。预计未来几年仍会有较快增长,2008年硫酸生产能力将达75 000kt/a,产量达60000 kt,此后可能小幅平稳增长甚或负增长。2005年我国硫酸表观消费量48 200 kt,其中化肥消费33 400 kt,占69．3％,磷肥用酸及钛白粉、氟化氢及粘胶纤维等工业用酸增长较快。磷肥工业的过快发展可能会对硫酸需求带来不利影响。