Thermal comfort assessment and energy consumption analysis of ground-source heat pump system combined with radiant heating/cooling

A new ground source heat pump system combined with radiant heating/cooling is proposed, and the principles and the advantages of the system are analyzed. A demonstration of the system is applied to a rebuilt building： Xijindu exhibition hall, which is located in Zhenjiang city in China. Numerical studies on the thermal comfort and energy consumption of the system are carded out by using TRNSYS software. The results indicate that the system with the radiant floor method or the radiant ceiling method shows good thermal comfort without mechanical ventilation in winter. However, the system with either of the methods should add mechanical ventilation to ensure good comfort in summer. At the same level of thermal comfort, it can also be found that the annual energy consumption of the radiant ceiling system is less than that of the radiant floor system.

Based on the water source heat pump system operation control and energy consumption optimization

The contradiction between the increasing material demand and resource,is the country has faced problems,to better solve the material demand and the contradiction between the environment and resources,is applied to the development of new energy,new energy,not only can alleviate people and resources,environment and resources,the contradiction between people and the environment,also can promote the sustainable development of world economy,HVAC technology has emerged a new generation of energysaving technology,HVAC has the characteristics of low consumption,low pollution,is a development of technology,to be promoted for environmentfriendly,resource-conserving society has an important role in promoting.This paper focuses on the HVAC technology,water source heat pump system operation control and energy consumption optimization,for the relevant personnel reference.

Synthesis and Design of Distillation Columns for Wide-Boiling Binary Mixtures with Vapor Recompression Heat Pumps

The vapor recompression heat pump(VRHP) distillation technology offers significant improvements in energy efficiency for distillation systems with small temperature differences between the top and bottom of the column. However, the separation of wide-boiling binary mixtures leads to substantial temperature differences between the top and bottom of the column. This limits the applicability of conventional VRHP due to high capital costs and strict performance requirements of the compressor. To overcome these challenges and to accommodate compressor operating conditions, a novel synthesis and design method is introduced to integrate VRHPs with wide-boiling binary mixture distillation columns(WBMDCs). This method enables quick determination of an initial configuration for the integrated WBMDC-VRHP system and helps identify the optimum configuration with the minimum total annual cost. Two examples, namely the separation of benzene/toluene and isopropanol/chlorobenzene, are employed to derive optimum configurations of the WBMDC-VRHP and compare them with the WBMDC. A systematic comparison between the WBMDC-VRHP and WBMDC demonstrates the superior steady-state performance and economic efficiency of the WBMDC-VRHP.

Analyses of influence of residential buildings' space organization on heating energy consumption in Lhasa

The heating load simulation models of the residential buildings in Lhasa are established for enhancing the space organization’s adaptability to climate and radiation and improving its energy saving performance.The space organization items a e analyzed for both the existing buildings without insulation and new buildings with good insulation.The items include orientation design,south a d north balcony design,the north and south partition wall’s position design,storey height design and window-wall ratio design.Simulation results show that orientation is the key design element for energy saving design,and adverse orientation can obviouslyincrease heating energy consumption;south and north balconies can reduce winter heating energy consumption;partition walls move to the north,which means that the south room’s big depth design leads to less heating energy consumption,but the effect is not inconspicuous;smaier storey height results in less heating load.For the existing buildings,the window-wall ratio of south side has a balance point for energy saving design in the calculation condition.For the new buildings with good insulation,enlarging the south window-wal ratio can continuously reduce heating energy consumption,but the energy saving rate between models gets smaier.The heating energy consumption comparison study between the common model and optimal space design model demonstrates that the energy saving design can significantly reduce heating energy consumption

Performance analysis of U-vertical direct-expansion ground-source heat pump

The performance of a direct-expansion ground-source heat pump（DX GSHP）system is theoretically analyzed.Compared with the conventional ground-source heat pump（GSHP）,the DX GSHP has a lower condensing temperature in the cooling mode and a higher evaporating temperature in the heating mode,and the ground heat exchanger（GHE）in the DX GSHP has a low thermal resistance.Therefore,the coefficient of performance（COP）of the DX GSHP is higher than that of the GSHP.In addition,the system performance of the DX GSHP system is higher than that of the conventional GSHP system because there are no secondary solution loops and water circulating pumps in the DX GSHP system.The experimental energy performance of the DX GSHP system is also investigated based on the actual operational data.The tested DX GSHP system is installed in Xiangtan,China.The U-vertical GHE of the DX GSHP is buried in a water well.The length and the outside nominal diameter of the GHE are 42 m and 12.7 mm,respectively.The experimental results show that the maximum（COP）and the average COP of the DX GSHP system in the heating mode are 5.95 and 4.72,respectively.

基于机器学习的空气源热泵干燥能耗回归预测

为了降低空气源热泵干燥过程能耗,研究了空气源热泵干燥能耗特性,采用多元线性回归模型(multivariate linear regression model, MLRM)和BP神经网络(back propagation neural network, BPNN)模型来预测干燥工艺能耗。在分析干燥能耗影响特征参数的基础上,提出将干燥工艺过程进行切分处理的方法以降低数据获取难度。选取烘房设定温度、烘房设定湿度、烘房初始温度、烘房初始湿度、环境平均温度、环境平均湿度、物料质量和初始含水率8个特征参数作为模型输入,能耗和物料结束含水率作为模型输出。使用MLRM模型、BPNN模型和其他机器学习模型进行能耗预测,MLRM模型对能耗拟合的决定系数为0.739,对物料结束含水率拟合的决定系数为0.931;BPNN模型使用Sigmoid函数作为激活函数时对能耗拟合的决定系数最高,为0.828,使用Identity函数作为激活函数时对物料结束含水率拟合的决定系数最高,为0.942,拟合效果优于其他机器学习模型,能够满足实际生产需求。以复水豌豆为干燥对象设计加载物料65 kg、持续时间4 h的完整变温变湿干燥工艺进行验证试验,结果表明:试验总能耗为15.066 kW·h,MLRM模型和BPNN模型的预测总能耗分别为14.476 kW·h、15.183 kW·h,预测精度分别为96.08%、99.23%;试验结束含水率为8.541%,MLRM模型和BPNN模型的预测结束含水率分别为9.560%、8.889%,预测精度分别为88.07%、95.93%。该研究提出了一种使用MLRM模型和BPNN模型对空气源热泵干燥能耗进行分段精准预测的有效手段,对于优化干燥工艺和降低干燥能耗具有实际意义。

某油田联合站污水余热利用研究

原油集输系统中的热化学沉降脱水,需要将原油温度升高,这一过程将消耗大量能源,其燃料主要为天然气,加热产生大量的CO_(2)。文中通过对某油田联合站生产流程研究分析,同时结合站内用热情况,确定采用压缩式热泵替代现有燃气加热炉技术路线,用于冬季采暖和一段原油加热。项目实施后,每年可节能源8932×10^(4) MJ,折合标煤减少3481.8 t,减少CO_(2)排放2024.5 t,每年可节省能源消耗费用651.8万元,节能减排效果显著,该研究对油田联合站清洁能源替代,减少CO_(2)排放具有重要意义。

基于联邦学习的分布式电采暖互动模式设计与展望

随着“双碳”目标的提出,以及“以电代煤”政策的贯彻落实,大量电采暖设备取代传统燃煤取暖投入运行并接入电网将成为必然趋势。大量电采暖设备可以作为需求侧可调资源进行新能源消纳,但是分布式电采暖所处地理区域较为分散,传统集中式管理的方式又存在隐私泄露、数据孤岛等问题。联邦学习作为一种分布式技术可在保护隐私的前提下支撑电采暖负荷互动,在分布式电采暖互动领域具有较强的适用性。分析了基于联邦学习的分布式电采暖互动需求,以及边缘缓存、隐私防护、通信传输优化和异构资源融合等技术在基于联邦学习的电采暖互动场景中的应用方式,并展望了未来基于联邦学习的分布式电采暖互动前景。

耗能不花钱的发动机设计

热泵产生的热量是输入电能的COP倍,COP=3-6,利用其能效高的特点,设计了热泵发动机,将热泵的热利用引申到一个新的领域——热泵的机械利用;为了提高热机效率,采用了将热泵串联起来升温的方法,又将热泵热利用引申到另一个新的领域——热泵的高温利用。综合以上两个领域的研究,设计出了一种耗能不花钱的发动机,指出了该发动机带来的三个有益效果:一是不用花钱就能输出能量,二是大力推广就解决了能源危机,三是减少了温室效应,有利于早日实现“双碳”目标。

住宅户内空气源热泵生活热水系统循环恒温能耗分析

基于3个住宅户型案例的空气源热泵生活热水系统,对系统配水管道采用循环恒温方式维持热水用水温度时的管道散热量进行计算评估,分析了循环恒温不同运行模式下的增量能耗和电耗,提出当前全装修住宅空气源热泵热水设备应集成管道恒温循环装置及控制装置等建议。

热泵-减压膜蒸馏工艺优化及能效分析

针对热泵-膜蒸馏过程中热量不平衡问题展开试验研究,采用两支减压膜蒸馏组件并入料液循环流路,使其分别发挥热量回收及排放富余热量的作用,实现热泵系统的热量平衡.通过试验测试,显示MD1200和MD200被认为是最佳双膜组合.采用该双膜组合进行连续8 h的含盐料液处理,结果显示,双膜组合可以获得稳定、连续的膜蒸馏运行效果,总产水量平均为1.9 L/h,系统比能耗最高310 W·h/kg产水,能耗性能优于无热量回收的膜蒸馏工艺,与已工业化的多效膜蒸馏工艺相当,有望成为可获得工业应用的低能耗膜蒸馏新工艺.

某住宅建筑空气源热泵采暖系统能耗优化分析

针对青岛某户式空气源热泵系统冬季供暖测试中存在的问题,如房间温度超标、无人时房间也开启供暖等,进一步对系统的运行控制进行了优化模拟。通过调整室内温度设定值及考虑房间使用时间等,分析了不同控制方式下的系统能耗情况。结合房间实际使用情况,建筑2层房间仅在周末时使用,对此进行了房间供暖末端的启停设置。在采暖设定温度与实测温度相同时,通过关闭2层不使用的房间供暖末端进行系统控制,单位建筑面积能耗和电耗分别下降21.1%和20.9%。当供暖季所有房间供暖末端开启时,室内温度均按照集中供热室内设计采暖温度18℃设定,单位面积能耗和电耗分别为81.7 kW·h/m^(2)、22.1 kW·h/m^(2),较实际系统下降了23.7%、21.4%;当房间2层供暖末端仅周末开启时,室内温度设定为18℃,单位建筑面积能耗和电耗分别降低为58.4 kW·h/m^(2)、15.5 kW·h/m^(2)。与实测能耗相比,通过运行优化控制,单位建筑面积供热量最大可降低45.4%,耗电量降低44.9%。相关分析结果为空气源热泵户式独立供暖系统的节能运行提供了参考。

基于压缩式热泵的CO_(2)-MDEA/PZ碳捕集工艺优化

当前化学法CO_(2)捕集系统的高投资、高吸收液再生能耗和高运行费用成为限制其大规模应用的主要障碍。为了回收解吸塔塔顶蒸汽中的潜热与显热,促进解吸反应的进行,利用Aspen plus软件建立基于压缩式热泵技术的有机胺法捕集CO_(2)流程模拟模型,主要探究了解吸塔塔底压力、进解吸塔富液温度、有机工质气化率以及工艺流程对CO_(2)再生过程的影响。结果表明:有机工质R123制热系数较R141b和R245fa高,其性能系数(COP)高达2.35,而排气温度较R141b和R245fa更低。压缩式热泵采用R123为循环工艺介质,热泵回收的热量用于加热贫富液换热器后的热富液以降低吸收液再生能耗。综合考虑解吸系统的再生能耗、工质循环量和解吸效果,通过12级位置注入15%的富液比合适。热泵回收余热工艺的投资回收期为0.82 a,具有较高的经济价值。

面向清洁电力消纳的中深层地埋管热泵蓄能系统设计方法研究

电驱动热泵技术在为建筑提供清洁冷热的同时,也成为了与电网协同、消纳清洁电力的关键环节。本文以电驱动热泵技术为核心,冬季供热采用中深层地埋管提供高品位低温热源,夏季供冷结合冷却塔技术构建高效冷热供应系统。在此基础上结合用户侧蓄能技术,实现日间冷热蓄存,同时以充分消纳本场光伏发电及市政清洁电力为目标提出了系统的设计方法与运行控制策略。随后以我国某大型公共建筑为例开展了定量分析,以明确其实际节能减排效果。

探讨城市集中供热管网的优化设计

随着城市化进程的不断加快,城市供热需求呈现出日益增长的趋势。城市集中供热作为一种高效、经济的供热方式,得到了广泛应用。然而由于城市供热管网的规模较大、复杂度较高,时常存在着能源浪费、供热效果不佳等问题。因此,对城市集中供热管网进行优化设计具有重要的理论和实际意义。首先阐述了城市集中供热管网的优势,接着对当前供热管网设计存在的问题进行分析,并在优化设计上给出了相应对策,希望能给相关领域人员一定的参考和借鉴。

储能协调下负荷密集区分布式综合能源系统优化研究

分布式综合能源系统是提高清洁能源使用比例,实现碳减排和碳中和目标的一种配套技术。因此,针对负荷密集区冷热电负荷供需矛盾问题,提出储能协调下的负荷密集区分布式综合能源系统,并构建数学模型。其次,确立考虑系统经济、能耗、环境性能的多目标优化模型,利用层次分析法确定不同优化指标之间的权重关系。建立由住宅、办公、酒店、商场四类建筑组成的负荷密集区建筑模型,分别对四类建筑全年的逐时冷热电负荷进行模拟。最后,对比分析四类建筑分别单独设置供能系统和考虑四类建筑负荷耦合互补设置一套供能系统时的系统容量配置优化以及在相关政策影响下的系统性能。结果表明:无论是否加入储能系统,考虑四类建筑负荷耦合互补设置一套供能系统时的系统性能优于四类建筑分别单独设置供能系统的性能。

寒冷地区新建农宅能耗测试及节能优化研究

通过对沧州地区某新建农宅进行室内热环境和围护结构采暖能耗的测试,研究新建农宅建筑采暖能耗现状和节能降耗策略,并利用DesignBuilder软件建立计算模型,根据当地农宅建筑特性选取了外墙构造、屋顶保温层材料、建筑层高、南向窗墙比、北向窗墙比等5个与采暖能耗相关的因素进行模拟优化分析。运用正交试验和极差分析,研究其对建筑能耗的影响趋势及显著性程度,最后得到新建农宅最佳优化方案为外墙选用250 mm厚EPS板层间浇筑混凝土外墙、屋顶保温层材料选用100 mm厚聚氨酯板、楼层高度选用3.2 m、南北窗墙比分别选择0.45和0.10,该组合单位面积采暖能耗为12.98 W/m^(2),对比实验建筑初始能耗节能率为40.81%。研究结果对于寒冷地区农宅节能设计及建造具有参考意义。

基于数据拟合的江水源热泵系统能效模型研究

采用数据拟合建立了制热工况下江水源热泵机组基础性能系数模型,在此基础上考虑蒸发器和冷凝器侧水温、水量对机组性能的影响,拟合得到变工况下江水源热泵机组制热能效模型;同时基于水泵“最小二乘法”拟合公式,建立了江水取水侧和用户侧水泵能耗模型。依托于重庆市某区域复合供能系统项目实测数据,机组能效模型误差为-5.84%~13.65%,输配系统能耗模型误差为-5.94%~9.99%,说明模型具有较高精确度,在0.2≤ε≤1.0,46℃≤t c,o≤54℃,5℃≤t e,i≤10℃,0.6≤n c≤1.2,0.6≤n e≤1.0范围内能够用于变工况下热泵机组和水泵能耗的有效预测。

机采系统优化设计软件应用与评价

为进一步摸索降低游梁式抽油机井单井能耗,提高游梁式抽油机井系统效率的高效途径,开展了机采系统优化设计软件现场应用。通过对比该优化方式与常规优化技术的参数差异,对检泵作业可优化调整的泵径、冲程和冲次等参数进行了深入细致的分析,建立软件模型,得出“大泵径、长冲程、低冲次”的设计理念,通过软件对生产井进行模拟优化。现场优化460口井,平均节电率达到34.18%,游梁式抽油机系统效率升高了11.92个百分点,取得了较好的节能效果,年创经济效益675.08万元,机采系统优化设计软件的应用为检泵井优化设计提供了手段。

色谱法提纯鱼油中EPA/DHA生产过程甲醇回收工艺对比

旨在为色谱法从鱼油中进一步分离纯化DHA和EPA生产企业甲醇废液回收工艺方案选择提供参考,介绍了普通单塔精馏、双效精馏、单塔热泵精馏和双塔热泵精馏4种甲醇回收工艺流程和主要参数,并以40t/h甲醇废液为例,利用AspenPlus软件对4种甲醇回收工艺路线的运行能耗做了模拟计算,对其成本进行了对比分析。结果表明:普通单塔精馏、双效精馏、双塔热泵精馏和单塔热泵精馏的冷却能耗和加热能耗依次降低;对比压缩机电耗在内的综合能耗(折合标煤),普通单塔精馏最高,双塔热泵精馏、单塔热泵精馏和双效精馏综合能耗分别是普通单塔精馏的34.2%、35.3%和56.5%;普通单塔精馏、双效精馏、单塔热泵精馏和双塔热泵精馏吨废液处理成本分别为137.8、78.0、57.7、51.2元/t;与单塔热泵精馏相比,双塔热泵精馏压缩机的压缩比可大大减小,可选机型多且技术成熟,设备采购费用降低。综上,双塔热泵精馏是最具竞争力的甲醇回收方案。