某热电供暖公司集中供热系统的节能分析

重点阐述换热站内部的调节及热力管网调节措施,并从实际案例分析供热系统的节能。通过在供热系统换热站安装自动化控制系统,在热力管网安装流量控制阀门,并采用正确的技术控制方法,提高了换热站内部调节的性能和换热站的监控手段,减小了外部管网的运行流量和水力平衡度,从而减少水、电、热等能源的浪费。     

换热站控制策略优化与节能的探讨

节能技术的应用成为现阶段我国供热行业的热门话题和关注的焦点。换热站作为供热系统连接管网与用户的一个重要环节,换热站的自动化程度和换热站的控制策略对系统的运行有着至关重要的作用,同时对热网的节能也有很重要的影响。结合换热站自动控制国内外的发展现状,介绍供热系统的调节方式,对换热站的控制策略进行优化。优化换热站的控制策略不仅可以提高换热站的供热品质,还可以实现节能目标,提升经济效益。     

智能热网技术在某小区的应用实例

针对目前冬季供暖二网侧普遍存在的水力失调及主要依靠经验进行二网供水温度调节的问题,首先通过加装动态压差平衡阀的方式进行水力平衡调节,然后基于换热站原PLC系统进行扩展,构建换热站"一站一优化"自动控制模块,实现换热站二网供水温度的智能调节。以某采暖面积8.34万m~2的小区为例,实施智能热网技术后,在保证热用户采暖舒适度的情况下,因水力失调引起的供热不均现象得到明显改善,换热站电耗减少16.7%,热耗减少15.9%,节能效果显著。     

响应终端用热控制的供热系统运行调节技术研究

针对当前推行的用热终端控制供热系统,进行换热站和热源侧供热运行调节技术研究。提出了基于管网末差压信号自动控制循环泵动力输出,以及基于供热系统特性的室外温度和二次侧流量控制热量供给的控制策略,并进行试验研究。研究发现,这种新型调节控制技术在实施分户热计量和具有终端用热控制功能的供热系统中实现按需供热和节热节电效果明显。     

城市热网智能调度系统的设计与应用

介绍某闭环控制系统通过换热站PLC采集温度、压力、水泵、阀门等的相关数据、状态,对水泵、阀门的控制,PLC的485接口标准协议通过无线4G DTU作为通讯通道与上位机组态进行实时通讯,上位机接收到大数据实时显示,存储到数据库,生成各种生产报表,对采集的大量数据进行分析,提出科学合理的运行方案,达到全网自动热力平衡,降低热耗、电耗,达到节能的目的。传统人工调控的方式由于效率低下、反应迟钝、失误较多,显然无法满足对日益庞大的供热网络的调控要求。热网监控系统通过采集、存储、统计和分析热网系统的运行参数,对供热设备进行实时的监控,并能根据要求对其工作参数进行有效调节,从而实现热源供热与用户用热之间的协调适应。     

基于物联网技术的热力站在线监测系统

为了贯彻城市集中供热热网质量并调的方针,响应环保与节能减排的号召,基于物联网与应用计算机控制技术,结合集散控制的思想,构建"物联网+热网控制"智能监控系统,设计了远程智能在线监测系统,使得远程监控中心可以与现场分散控制中心实现联合调控,可以依据换热站的现场采集现场变频调节、电能监测、大电流柜温湿度监测及控制、电机轴温、振动与噪音监测、环境温湿度监测、站内水浸、门禁系统、照明控制、视频监控等参数,实现了热网系统安全、稳定、节能地运行。     

计算机监控系统分段PID调节在水电站的应用

水电站机组负荷调节主要是以计算机监控系统给调速器发开出脉冲为主的开度调节模式。文中介绍了MB80系列可编程逻辑控制器的特点、机组PID调节的原理及要求,以及在调速器功率调节模式下进行机组负荷调节,分析了计算机监控系统2种不同的PID调节方式,通过调试,发现分段PID调节的调节效果较好。     

换热站由一次侧向二次侧直接补水全自动节能定压装置

对集中供热系统中换热站进行优化设计,换热站采取一次侧向二次侧直接补水的全自动节能定压装置,包括控制器、换热器、一次侧热网回水管、二次侧热网补水管。它取消了传统系统中的水处理装置、补水水箱,极大地简化了补水定压系统的设备;节省了换热站占地面积,节约了投资。     

换热站供暖系统分阶段等温差控制技术

为了控制建筑不同时段内室内温度差，提高供热系统服务质量，开展换热站供暖系统分阶段等温差控制方法的设计研究。根据前端用户的实际需求，确定系统的供水温度与室内温度之间的关系，计算在影响周期范围内，供热系统运行的失热量与供热量，累加计算两者的差值。此数值超出某一时段的数值时，启动供暖系统的补偿程序，驱动换热站供暖系统供热补偿行为；设计换热站热网的主动调节，提出基于热力调控的分阶段等温差控制方法，实现对温度的有效调控。以某地区居民建筑为例，设计实例应用实验。结果显示：提出的方法可以将建筑室内温度控制在供暖系统温度标准界限以上，有效控制建筑不同时段内室内温度差，以此提高供热系统的运行质量。     

换热站节能控制系统的设计与应用

简要叙述了换热站设备的基本构成和工作过程。根据换热站供暖技术要求,采用PID调节器、PLC和变频器,设计了换热站节能控制系统,并给出具体的电路设计图。通过采用电动阀门、PID调节器、PLC和变频器对换热站设备进行自动控制,大大提高了设备的供热能力,维修方便,使换热设备更加安全可靠运行,并节省了大量的能源。     

A district heating system based on absorption heat exchange with CHP systems

In order to decrease the energy consumption of large-scale district heating systems with cogeneration, a district heating system is presented in this paper based on absorption heat exchange in the cogeneration system named Co-ah cycle, which means that the cogeneration system is based on absorption heat exchange. In substations of the heating system, the temperature of return water of primary heat network is reduced to about 25°C through the absorption heat-exchange units. In the thermal station of the cogeneration plant, return water is heated orderly by the exhaust steam in the condenser, the absorption heat pumps, and the peak load heater. Compared with traditional heating systems, this system runs with a greater circuit temperature drop so that the delivery capacity of the heat network increases dramatically. Moreover, by recovering the exhausted heat from the condensers, the capacity of the district heating system and the energy efficiency of the combined heat and power system (CHP system) are highly developed. Therefore, high energy and economic efficiency can be obtained.     

A district heating system based on absorption heat exchange with CHP systems

In order to decrease the energy consumption of large-scale district heating systems with cogeneration, a district heating system is presented in this paper based on absorption heat exchange in the cogeneration system named Co-ah cycle, which means that the cogeneration system is based on absorption heat exchange. In substations of the heating system, the temperature of return water of primary heat network is reduced to about 25°C through the absorption heat-exchange units. In the thermal station of the cogeneration plant, return water is heated orderly by the exhaust steam in the condenser, the absorption heat pumps, and the peak load heater. Compared with traditional heating systems, this system runs with a greater circuit temperature drop so that the delivery capacity of the heat network increases dramatically. Moreover, by recovering the exhausted heat from the condensers, the capacity of the district heating system and the energy efficiency of the combined heat and power system (CHP system) are highly developed. Therefore, high energy and economic efficiency can be obtained.     

Inverse problem and variation method to optimize cascade heat exchange network in central heating system

Urban heating in northern China accounts for 40％ of total building energy usage.In central heating systems,heat is often transfened from heat source to users by the heat network where several heat exchangers arc installed at heat source,substations and terminals respectively.For given overall heating capacity and heat source temperarure,increasing the terminal fluid temperature is an effective way to improve the thermal performance of such cascade heat exchange network for energy saving.In this paper,the mathematical optimization model of the cascade heat exchange network with three-stage heat exchangers in series is established.Aim at maximizing the cold fluid temperature for given hot fluid temperature and overall heating capacity,the optimal heat exchange area distribution and the medium fluids' flow rates are determined through inverse problem and variation method.The preliminary results show that the heat exchange areas should be distributed equally for each heat exchanger.It also indicates that in order to improve the thernmal performance of the whole system,more heat exchange areas should be allocated to the heat exchanger where flow rate difference between two fluids is relatively small.This work is important for guiding the optimization design of practical cascade heating systems.     

Evaluation and optimization of water source heat pump for district heating: A case study in steel plant

Using high-temperature heat pump technology to recover waste heat of circulating cooling water in a steel plant for central heating system not can only reduce the temperature of circulating cooling water to meet the needs of smelting process but also can save energy and protect environment as well as bring great economic benefits to steel plant that can sell heat to the heat users. The energy consumption equation of heat pump central heating system was established based on the energy consumption of heat pump, energy consumption of water pump, and heat loss. The optimal inlet water temperature, inlet flow rate, and the number of operating heat pump modules at different outdoor temperatures were calculated by genetic algorithm. The superiority and operating control strategy of heat pump central heating system were discussed. The results show that with the increase of outdoor temperature, the optimal inlet flow rate and the number of operating heat pump module decrease. However, the inlet water temperature almost does not change. It is more suitable for the heat pump central heating system to change the inlet flow and the number of operating heat pump modules. The operating control strategy equation was established by linear fitting, which provides guidance for the engineering application of heat pump central heating system.     

Numerical optimization of a solar air heating system based on encapsulated P.C.M. storage

A ransient olar etwork imulation (TSUNS) code of a solar air heating system using ock ed nergy torage (RBES) or hase hange nergy torage (PCES) is presented. Solar fraction obtained by TSUNS with RBES under Belgian climatic conditions are compared with Fchart results. The storage working times are compared between Belgiam and U.S. climates. Use of PCES in a solar air heating system provides an easy way to control over-heating. Solar fraction of such systems can be improved by suitable adjustment of parameters such as hase hange aterial (PCM) fusion temperature, latent heat and storage heat exchange properties. Comparisons between RBES and PCES (CaCl₂6H₂O) are drawn in thermal and parasitical power field.     

模糊理论结合PID控制方法在集中供热系统中的应用

集中供热系统是一个具有大惯性、纯滞后特点的复杂非线性系统,为了提高系统稳定性,实现合理用热,将模糊自适应控制和常规PID控制两种控制方法结合并使用模糊工具箱进行了系统仿真实验。实际结果表明,同常规的PID控制方法相比,模糊自适应PID控制方法有效提高了集中供热系统的鲁棒性、稳定性和自适应的能力。在集中供热的复杂系统中,能更好的满足用户的热需求     

采用神经网络:模糊PID的换热站控制器设计与仿真

针对换热站质调、量调通道之间的耦合作用和控制模型参数时变的问题,提出一种新的神经网络:模糊PID换热站控制器结构。通过现场采集换热站质调、量调通道阶跃信号响应,并利用最小二乘辨识得到质调、量调通道的控制模型。利用得到的质调、量调通道控制模型,对设计的神经网络:模糊PID控制器进行仿真实验,仿真研究表明该控制器能够有效实现质调、量调通道的解耦,减小控制模型时变对控制品质的影响。     

热平衡在中储式制粉系统一次风、粉试验中的应用

电站锅炉煤粉浓度是锅炉风粉系统的一个重要监测参数,对于锅炉的燃烧调整和安全运行起着极为重要的作用,利用软仪表测量原理,研究了电站风粉浓度测量的软测量模型。通过热平衡原理计算能够较准确地反映煤粉的浓度,具有工程实用价值,并且应用于某电厂中储式制粉系统一次风、粉试验中,收到了较好的效果。     

带有小螺旋角的内外螺旋翅片管高压加热器的工业试验

工业现场试验的结果表明,带有小螺旋角的内外螺旋翅片管（简称内外螺旋翅片管或ＩＯＳＦ管）用于电站高压加热器有着显著的传热强化效果,其实测总传热系数是光滑管加热器的１．４３倍,可相应节省换热面积３０％。在等面积下使用,则可收到明显的节能效果。