Exploration and Application Practice of Energy Conservation Theory and Method in Steel Manufacturing Process System

This article briefly discusses the theoretical basis and overall goals of energy conservation in the steel manufacturing process system.It is proposed that in the process of implementing system energy conservation,it is necessary to fully recognize and utilize the characteristics and functional advantages of the steel manufacturing process,pay more attention to energy quality,firmly grasp the overall goal of system optimization,focus on the integrated optimization of gas,steam,and waste heat systems,and propose the idea of constructing a"steel chemi-cal gas electricity heating cooling multi generation system".Based on practice,the main principles,models,and effects of implementing systematic energy conservation in steel enterprises have been proposed.

Analysis and Prospect of Waste Heat Utilization from Blast Furnace Slag Flushing

Estimating the residual heat of blast furnace slag flushing in China,classifying and introducing the current proposed methods of slag flushing waste heat utilization,and listing existing cases.In order to better save energy and water in the slag flushing process of blast furnaces,an ideal comprehensive cascade utilization system scheme for annual recovery of waste heat is proposed.Based on the measured waste heat data of a steel plant,design calculations are carried out to further analyze the economic feasibility of the new scheme and provide reference for its promotion and application.

The Develoyment Program of Energy Conservation and Comprehensive Utilization 2005-2007

Jointly published by 14 Department headed by Standardization Administraion ofChina(SAC) Subtitle: China will formulate and reformulate 926 standards for energy conservation andcomprehensive u-tilization during 2005 and 2007. In the past few days, 14 departments jointlypublished the Development Program of Energy Conservation and Comprehensive Utilization 2005-2007,(Program for short). They are Standardization Administration of China, National Development andReform Commission, Ministry of Land and Resources, Ministry of Establishment, Ministry ofCommunications, Ministry of Information Industry, Ministry of Waster Resources, Ministry ofAgriculture, Ministry of Commerce, General Administration of Quality Supervision, Inspection andQuarantine of the PRC, State Environmental Protection Administration, State Forestry Bureau, StateOceanic Administration and China Meteorological Bureau.

Integration of Low-level Waste Heat Recovery and Liquefied Nature Gas Cold Energy Utilization

Two novel thermal cycles based on Brayton cycle and Rankine cycle are proposed, respectively, which integrate the recovery of low-level waste heat and Liquefied Nature Gas （LNG） cold energy utilization for power generation. Cascade utilization of energy is realized in the two thermal cycles, where low-level waste heat,low-temperature exergy and pressure exergy of LNG are utilized efficiently through the system synthesis. The simulations are carried out using the commercial Aspen Plus 10.2, and the results are analyzed. Compared with the conventional Brayton cycle and Rankine cycle, the two novel cycles bring 60.94% and 60% in exergy efficiency, respectively and 53.08% and 52.31% in thermal efficiency, respectively.

Current Situation and Suggestions for Energy Utilization of Agricultural Waste in Hubei Province

Energy utilization is high-value use pattern of agricultural waste, and is main development direction of agricultural biomass energy industry in China. Planting and breeding industry in Hubei Province occupies important position in whole country. Agricultural waste resources are rich, and it has huge potential for developing agriculturel biomass energy. By statistical data during 2000 -2011, we analyzed current situation and problem for energy utilization of agricultural waste in Hubei Province, and put forward several countermeasures and suggestions, vigorously promoting energy utilization of agricultural waste.

Analysis and Economic Evaluation of Hourly Operation Strategy Based on MSW Classification and LNG Multi-Generation System

In this study,a model of combined cooling,heating and power system with municipal solid waste(MSW)and liquefied natural gas(LNG)as energy sources was proposed and developed based on the energy demand of a large community,andMSW was classified and utilized.The systemoperated by determining power by heating load,and measures were taken to reduce operating costs by purchasing and selling LNG,natural gas(NG),cooling,heating,and power.Based on this system model,three operation strategies were proposed based on whether MSW was classified and the length of kitchen waste fermentation time,and each strategy was simulated hourly throughout the year.The results showed that the strategy of MSW classified and centralized fermentation of kitchen waste in summer(i.e.,strategy 3)required the least total amount of LNG for the whole year,which was 47701.77 t.In terms of total annual cost expenditure,strategy 3 had the best overall economy,with the lowest total annual expenditure of 2.7730×108 RMB at LNG and NG unit prices of 4 and 4.2 RMB/kg,respectively.The lower heating value of biogas produced by fermentation of kitchen waste from MSW being classified was higher than that of MSW before being classified,so the average annual thermal economy of the operating strategy of MSW being classified was better than that of MSW not being classified.Among the strategies in which MSW was classified and utilized,strategy 3 could better meet the load demand of users in the corresponding season,and thus this strategy had better thermal economy than the strategy of year-round fermentation of kitchen waste(i.e.,strategy 2).The hourly analysis data showed that the net electrical efficiency of the system varies in the same trend as the cooling,heating and power loads in all seasons,while the relationship between the energy utilization efficiency and load varied from season to season.This study can provide guidance for the practical application of MSW being classified in the system.

Integrated utilization of low-grade thermal energy in hot coal mine

This paper explores the integrated utilization of low-grade thermal energy in hot coal mines, based on analysis of original heating, refrigerating, mine draining, bath draining and air exhaust systems, and in combination with the actual conditions of Tangkou Coal Mine in Shandong Province. It presents a set of comprehensive and integrated utilization schemes for the various different kinds of low quality heat energy. With heat pumps, the recycling of the low quality heat energy from the drainage, bathing water and the exhaust air can occur in winter, and in summer, there exists condensed heat of the refrigerating system. When in conjunction with solar collectors, the thermal utilization of solar power can be realized for the whole year. The system achieves mine drainage and bathing water purification and recycling, as well as purifying exhaust air by water spraying. It also satisfies the demands of a whole year＇s bathing heat for the coal mine, with refrigeration in summer, and heating for the ground house and shaft house in winter. It is able to integrate different kinds of low quality heat energy and low emission drainage and dust, and can replace the traditional boiler heating system. Finally, the system reduces conventional energy consumption and the amount of mine water drainage.

Diesel generator exhaust heat recovery fully-coupled with intake air heating for off-grid mining operations:An experimental,numerical,and analytical evaluation

The customarily discarded exhaust from the fossil fuel-based power plants of the off-grid mines holds the thermal potential to fulfill the heating requirement of the underground operation.This present research fills in an important research gap by investigating the coupling effect between a diesel exhaust heat recovery and an intake air heating system employed in a remote mine.An integrative approach comprising analytical,numerical,and experimental assessment has been adapted.The novel analytical model developed here establishes the reliability of the proposed mine heating system by providing comparative analysis between a coupled and a decoupled system.The effect of working fluid variation has been examined by the numerical analysis and the possible improvement has been identified.Experimental investigations present a demonstration of the successful lab-scale implementation of the concept and validate the numerical and analytical models developed.Successful deployment of the fully coupled mine heating system proposed here will assist the mining industry on its journey towards energy-efficient,and sustainable mining practices through nearly 70%reduction in fossil fuel consumption for heating intentions.

余热余压空气梯级利用的双涡流管有机朗肯循环综合性能分析与优化

为充分利用工业生产中的余热余压空气能量,同时降低ORC系统冷凝热损失,该文提出一种双涡流管ORC系统(ORC coupled with double vortex tubes,DVT-ORC)。利用热源涡流管将放热后的余热余压空气分离成冷、热空气,冷空气用于工质冷却,热空气作为二级蒸发器的热源且换热后其余压用于驱动气动增压泵;利用工质涡流管将透平乏气分离成冷、热气流,热气流经气动增压泵升压再循环,冷气流进入空气冷却器冷却。以150℃、0.6 MPa的空气为初始热源,R245fa为工质,建立热力与经济的多目标优化模型,分析双涡流管冷流比和透平排气压力对系统综合性能的影响;采用遗传算法进行优化,确定系统最优工况。结果表明:当热源涡流管冷流比大于0.3时,DVT-ORC输出功大于基本ORC输出功,工质涡流管与空气冷却器的㶲损失之和较基本ORC系统冷凝器的㶲损失最大可减小1240.32 kW,单位电力生产成本较低,DVT-ORC系统热力性与经济性提升。系统最佳运行工况在透平排气压力为0.3007 MPa、工质涡流管冷流比为0.8738、热源涡流管冷流比为0.8942时,对应的净输出功为173.94 kW、热效率为13.57%、单位电力生产成本为0.415元/(kW·h)。

集成碳捕集的1000 MW超超临界燃煤机组热力系统优化与性能研究

为降低CO_(2)的能耗并且提高发电效率,以超超临界二次再热-碳捕集系统为参考系统,提出了耦合太阳和ORC系统的二次再热-碳捕集优化方案。利用Ebsilon软件构建了优化系统模型,并进行了热力性能、经济性和运行性能分析。结果表明:与参考系统相比,优化系统热效率提高了4.78%,热耗降低了1005 kJ/(kW·h),煤耗降低了36.50 g/(kW·h);太阳能辅助系统年运行时间占比为60%,均省煤量可达到2.0×10^(4)t。优化方案具有更好的热经济性并且减少了发电耗煤量,为CO_(2)捕集和减排提供优化思路。

海上平台烟气余热利用分析与工艺优化

依托南海某在建钻采平台,从工艺原理、工艺流程、有机工质的选择、安全性、能源节约及降低二氧化碳排放等方面进行分析,论证有机朗肯循环(Organic Rankine Cycle,ORC)技术在海上平台应用的可行性。根据能量梯级利用原则,设计一套优化的烟气-导热油-热用户系统,利用透平废热实现ORC发电、生产系统加热及溴化锂制冷的热电冷联产系统。

炼油厂胺液再生装置节能优化措施应用

醇胺法脱硫是炼油厂最常用的脱硫方法之一,其溶剂N–甲基二乙醇胺更因具有选择性高、再生效果好、不易降解、价格低廉等诸多优点被广泛使用。该文对胺液再生装置能耗现状进行分析,通过对系统胺液提浓降量,引常减压蒸馏装置0.4 MPa蒸汽至再生塔底重沸器,对贫胺液泵进行叶轮切削,更新贫胺液冷却器等措施降低装置能耗。项目实施后减少了1.0 MPa蒸汽、电能和循环水的消耗,增加了装置间低压蒸汽的利用,装置年综合能耗降至3 217 373 kgOE,单位能耗降至3.72 kgOE/t,有效降低了装置能耗。

温度对废弃生物质热解规律及产物分布的影响

为探究有机固体废弃物热解规律及产物分布,以不同原料(木屑、污泥、生活垃圾)为研究对象,利用一级固定床反应系统研究持续升温下不同生物质热解性能的变化规律。结果表明:高温有利于促进生物质热解、提高热解气产率、降低焦油产率,尤其木屑热解受温度变化作用显著;木屑、污泥、生活垃圾经高温热解后焦油所含有机物的分布差异明显,其中木屑热解油中未检测出酸类物质,酚类、醇类物质占比随温度变化明显增加,酮类化合物占比变化不大;进一步通过不同指标论证了生物质热解制备高值燃气的可行性,得出生物质高温热解气具有很好的协同作用和良好的应用前景,是生物质高值化利用的重要方向,也是绿氢产生的重要途径。

一种智控型烟气余热深度回收装置的实践探索

为了解决大庆油田加热炉排烟温度高、生产能耗大的问题,在加热炉排烟系统增设智控型烟气余热深度回收装置,以加热炉进液为冷源,将排烟温度冷却至50℃以下,综合回收烟气的显热和潜热,达到深度回收烟气余热的目的,并对烟气降温过程中产生的冷凝水进行全部回收,从根本上解决了冷凝水排放问题。应用装置前后系统整体热效率分别为79.94%和87.47%,综合计算得到装置的节能率为8.35%,节能效果显著;此外,对于1.0 MW加热炉,年平均负荷率50%,年运行时间330 h,测算得到每年节约天然气4.58×10^(4) m^(3),折合7.4万元,具有良好的经济效益。

废旧塑料低碳经济发展与优化路径

全球经济规模持续扩张造就的以牺牲环境为代价换取发展的模式,会导致环境污染与资源短缺,废弃物资源化利用与可持续发展的低碳经济理念是各行各业转型升级的必然选择。废旧塑料资源化利用作为低碳经济必不可少的构成部分,不仅节能减排还蕴藏着经济效益与生态效益。本文主要对废旧塑料低碳经济发展模式价值及其优化路径进行了深度分析,以期挖掘废旧塑料低碳发展潜力,推进塑料相关行业健康稳定发展。

溴化锂吸收式余热回收机组的设计

针对核电站低温余热回收利用的问题,将海水淡化技术与基于吸收式热交换的热电联产集中供应技术相结合,设计了一个溴化锂吸收式余热回收机组。该机组主要由蒸发器、吸收器、发生器、冷凝器、溶液热交换器、节流装置、溶液泵、冷剂泵等组成。验证分析表明:该机组可有效回收高温海水的余热,并用于淡化海水,在所需制热量为28784 kW的前提下,按年利用7200 h计算,全年海水的余热回收量约280000 GJ,全年淡水产量约2160000 t,减少了对生态环境的影响,大大提高了经济效益。因此该机组可为溴化锂吸收式热泵机组的优化设计提供良好参考。

生物质好氧发酵热生产与回收利用研究进展

好氧发酵是目前有机固体废弃物处理的一种有效手段。人们对于好氧发酵的研究主要集中在高效有机肥的获取上,但发酵过程产生的热能不容忽视。发酵热作为一种“零碳”能源,可代替传统化石能源应用于加温供暖、生物干化等领域,助力实现“碳达峰、碳中和”。为将生物质能高效转化为热能利用,人们对发酵热回收利用进行了研究,但是没有将热生产、热回收和热利用三个阶段进行系统联系,导致热回收工艺效率不高。该文主要阐述了好氧发酵产热原理,并从菌剂、原料理化性质和发酵工艺三个方面对发酵热生产的影响进行了探讨,总结了现有热回收利用系统,最后对生物质好氧发酵热生产与回收利用系统的发展方向进行展望,以期为生物质发酵热能利用提供支持。

基于相变材料的蒸汽卡诺电池热力学循环设计

为了研究工业园区综合能源系统的多能互补新路线,提出基于高低温相变材料的新型蒸汽卡诺电池.建立计及设备性能与质量流量的热力学循环计算模型,分析设计参数、多级压缩结构对系统热泵系数、循环效率、储电损失与供热(火用)效率的影响.通过探究发现,低温相变材料的相变温度和高温相变材料的相变温度是影响蒸汽卡诺电池性能的主要因素,得到蒸汽卡诺电池的高循环性能区.优化蒸汽卡诺电池的参数与结构,结果表明,循环效率可达56.96%,热泵系数可达2.55,供热(火用)效率可达68.74%.

面向能效设计指数的LNG燃料船CO_(2)捕集系统设计及性能分析

为满足国际海事组织(International Maritime Organization,IMO)第三阶段船舶能效设计指数(energy efficiency design index,EEDI)的要求,提出一种液化天然气(liquefied natural gas,LNG)燃料船船载碳捕集系统(onboard carbon capture system,OCCS)。OCCS通过醇胺溶液对主机烟气中的CO_(2)进行富集,并回收主机烟气余热用于醇胺溶液再生,再利用LNG汽化过程中释放的冷能对解吸出的CO_(2)进行液化。以一艘Kamsarmax型船为例,构建基于冷热能综合利用的OCCS模型,分析烟气质量流量、溶剂质量流量和吸收塔进口处的贫液温度对CO_(2)捕集量及比热耗的影响。结果表明:提高贫液温度能够有效减少热量消耗,烟气和溶剂质量流量对CO_(2)捕集量影响显著,当溶剂质量流量大于18000 kg/h时,OCCS能满足IMO第三阶段的CO_(2)减排要求。该船通过所设计的OCCS可以满足IMO第三阶段EEDI的要求,其比热耗在10.9~12.2 GJ/t范围内。

基于太阳能和双有机朗肯循环的液态空气储能系统特性研究

为了解决传统太阳能蓄热式液态空气储能系统(LAES-S)余热利用不完全的问题,进一步提高系统的往返效率,文章在LAES-S系统基础上,构建了一个耦合太阳能蓄热和双有机朗肯循环的液态空气储能系统(LAES-S-O),并建立了耦合系统的热力学模型,分析了关键参数对系统性能的影响。结果表明:典型工况下,子系统ORC1和ORC2的净输出功分别为1296 kW和6695.83 kW;新系统的往返效率可达117.63%,火用效率为38.97%,能量效率为28.88%,与参考系统相比,分别提升了12.58%,2.35%,1.21%。此外,该系统还为用户提供了温度为364.15 K的生活热水,实现了热电联产功效。对关键参数的敏感性分析显示,当液化压力(末级压缩机出口压力)从15 MPa升高到18 MPa,液化温度(节流阀入口空气温度)从93.15 K上升到113.15 K时,空气液化率、往返效率、火用效率随液化压力的增大而降低,液化压力和温度的提高不利于系统性能的提升;但当排气压力从5.3 MPa升高至7.7 MPa时,往返效率、火用效率均随之升高。研究结果可为液态空气耦合太阳能系统提供一定的理论支持。