CO2捕集工艺中热再生气余热的PVDF/BN-OH平板复合膜回收特性

doi:10.16085/j.issn.1000-6613.2022-0926

摘要/Abstract

摘要：

围绕CO₂化学吸收工艺中热再生气的余热回收来开展研究。本文在CO₂化学吸收系统的再生塔顶增设换热器，利用分流的冷富CO₂吸收剂溶液来回收热再生气（CO₂和水蒸气混合气体）中的余热，可降低CO₂再生能耗，且余热回收性能越优，降耗效果越明显。采用膜换热器替代传统钢制换热器，利用余热回收过程中冷凝水的热质耦合传递，可强化余热回收性能。本文以聚偏氟乙烯（PVDF）为主体，添加羟基化氮化硼（BN-OH）共混改性，以聚酯纤维（PET）无纺布作为支撑层，制备了PVDF/BN-OH平板复合膜，并在乙醇胺（MEA）基富液分流化学吸收工艺中，探讨了复合膜的余热回收性能，同时与商业PVDF平板膜进行了对比。结果显示，与不添加BN-OH的M1膜相比，添加质量分数1%BN-OH的M3膜的平均孔径增加了约11.32%，而孔隙率仅下降了约7.14%，且依然保持亲水特性（水接触角为77.1°），同时热导率提高了约52.25%，说明M3膜具有强化热质耦合传递特性的潜能。与M1膜相比，在相同的操作参数条件下，M3膜的余热回收通量和热回收率最大可分别增加95.5%和31.6%。与具有更小厚度的商业化PVDF膜相比，M3膜的余热回收通量和热回收率最大可提高54.8%和9.6%，具有更优的余热回收特性。最后，通过拟合得出余热回收率与各试验因素之间的经验关系式。

关键词: 二氧化碳捕集, 传热, 传质, 跨膜冷凝器, 解吸

Abstract:

In this study, the waste heat recovery was concentrated from the hot stripped gas in CO₂ chemical absorption process. A heat exchanger could be added on the top of CO₂stripper in the CO₂ chemical absorption system to reduce the CO₂ regeneration energy consumption, which was fulfilled by recovering the waste heat from the stripped gas (i.e., the mixture of water vapor and CO₂) using the bypassed cold CO₂-rich solvent in the heat exchanger. Generally, a better waste heat recovery performance leaded to a low CO₂ regeneration energy consumption. The waste heat recovery performance could be enhanced by adopting the novel membrane heat exchanger to replace the traditional steel heat exchanger because of the coupled heat and condensate transfer in the membrane heat exchanger. A PVDF/BN-OH flat composite membrane was prepared through the blend modification method using polyvinylidene fluoride (PVDF) and hydroxylated boron nitride (BN-OH). In this composite membrane, the polyester fiber (PET) non-woven fabrics was used as the support layer. The waste heat recovery performance was experimented by using the prepared composite membrane in the monoethanolamine (MEA)-based rich-split process. Additionally, the commercial PVDF membrane was also adopted as the control. Compared with the prepared composite membrane without adding BN-OH (i.e., M1 membrane), the membrane adding 1% BN-OH (i.e., M3 membrane) achieved a higher average pore size by about 11.32%, a relatively lower porosity by about 7.14% and a higher conductivity by about 52.25%. Notably, M3 membrane still maintained the hydrophilicity with a water contact angle of 77.1°. Therefore, M3 membrane may have the potential to enhance the coupled mass and heat transfer performance. Under the same operation conditions, M3 membrane could obtain a waste heat recovery flux up to 95.5% higher than M1, and a heat recovery ratio up to 31.6% higher than those of M1 membrane. Compared to the commercial PVDF membrane with a smaller thickness, M3 membrane still had a maximum 54.8% higher waste heat recovery flux and 9.6% higher heat recovery ratio, suggesting the better waste heat recovery performance of M3 membrane. Finally, the empirical correlations between the waste heat recovery ratio and key operation parameters were proposed, which showed a high accuracy.

Key words: CO₂ capture, heat transfer, mass transfer, transport membrane condenser, desorption

中图分类号:

S216.4

尚玉, 肖满, 崔秋芳, 涂特, 晏水平. CO₂捕集工艺中热再生气余热的PVDF/BN-OH平板复合膜回收特性[J]. 化工进展, 2023, 42(3): 1618-1628.

SHANG Yu, XIAO Man, CUI Qiufang, TU Te, YAN Shuiping. Recovery characteristics of PVDF/BN-OH flat composite membrane for waste heat of hot stripped gas in CO₂ capture process[J]. Chemical Industry and Engineering Progress, 2023, 42(3): 1618-1628.

图/表 14

图1 改进型富液分流工艺流程

表1 不同膜的铸膜液配比（质量分数）

膜编号	BN-OH/%	PVDF/%	PVP/%	DMF/%
M1	0	14	5	81.0
M2	0.5	14	5	80.5
M3	1.0	14	5	80.0

图2 基于PVDF/BN-OH平板复合膜换热器的热再生气余热回收系统[13]

表2 试验中测定参数的不确定度

测定参数	不确定度	测定参数范围
富液进口温度/℃	0.1	44.6～64.5
富液进口流量/L·h^-1	0.01	0.6～2.04
富液出口温度/℃	0.1	55.4～78.9
再生气进口水流量/g·min^-1	0.025	0.964～3.54
再生气出口水流量/g·min^-1	0.01	0.1～3.32

表3 无纺布、商品膜和复合膜的基本特性参数

样品类型	PVDF膜面侧接触角/(°)	平均孔径/nm	孔隙率/%	热导率/W·m^-1·K^-1	拉伸强度/MPa	厚度/mm
M1	59.2±2.5	247.3	51.8	0.0511±0.001	39.0	0.24±0.020
M2	74.8±3.3	235.1	44.9	0.0586±0.001	42.4	0.23±0.030
M3	77.1±2.4	275.3	48.1	0.0778±0.003	35.3	0.20±0.015
PVDF商品膜	68.7±2.5	200.0	49.2	—	34.3	0.086±0.004
PET无纺布	85.8±5.0	2184.6	55.0	—	34.1	0.14±0.014

图3 不同复合膜的表面形貌M1-T、M2-T和M3-T所示的分别是BN-OH添加量为0、0.5%和1%时复合膜的PVDF膜面侧结构；M1-B、M2-B和M3-B图所示的分别是BN-OH添加量为0、0.5%和1%时复合膜的无纺布侧结构

图4 富液流量对系统热回收性能和水回收性能的影响（再生气流量0.18m3/h、再生气进口温度90℃、再生气中H2O(g)与CO2的摩尔比为2∶1；富液温度为45℃、MEA的质量分数为30%、CO2负荷为0.45mol/mol）

图5 富液温度对系统热回收性能和水回收性能的影响（再生气流量0.18m3/h、再生气进口温度90℃、再生气中H2O(g)与CO2的摩尔比为2∶1；富液流量为0.6L/h、MEA的质量分数为30%、CO2负荷为0.45mol/mol）

图6 再生气中H2O(g)和CO2摩尔比对系统热回收性能和水回收性能的影响（再生气流量0.18m3/h、再生气进口温度90℃；富液温度为45℃、富液流量为0.6L/h、MEA的质量分数为30%、CO2负荷为0.45mol/mol）

图7 再生气温度对系统热回收性能和水回收性能的影响（再生气流量0.18m3/h、再生气中H2O(g)和CO2的摩尔比为2∶1；富液温度为45℃、富液流量为0.6L/h、MEA的质量分数为30%、CO2负荷为0.45mol/mol）

图8 再生气流量对系统热回收性能和水回收性能的影响（再生气温度为90℃、再生气中H2O(g)和CO2的摩尔比为2∶1；富液温度为45℃、富液流量为0.6L/h、MEA的质量分数为30%、CO2负荷为0.45mol/mol）

图9 M3膜热回收率与主要试验因素的对数关系

图10 M3膜热回收率与主要试验因素的线性关系

图11 M3膜热回收率试验值与计算值的对比

参考文献 23

1	LIN Y J, MADAN T R, ROCHELLE G T. Regeneration with rich bypass of aqueous piperazine and monoethanolamine for CO₂ capture[J]. Industrial & Engineering Chemistry Research, 2014, 53(10): 4067-4074.
2	COUSINS A, COTTRELL A, LAWSON A, et al. Model verification and evaluation of the rich-split process modification at an Australian-based post combustion CO₂capture pilot plant[J]. Greenhouse Gases: Science and Technology, 2012, 2(5): 329-345.
3	CUI Qiufang, LIU Shuo, XU Liqiang, et al. Modification of rich-split carbon capture process using ceramic membrane for reducing the reboiler duty: Effect of membrane arrangements[J]. Separation and Purification Technology, 2020, 235: 116148.
4	CHEN Haiping, ZHOU Yanan, CAO Sutian, et al. Heat exchange and water recovery experiments of flue gas with using nanoporous ceramic membranes[J]. Applied Thermal Engineering, 2017, 110: 686-694.
5	宋增华, 方梦祥, 王涛, 等. 纳米陶瓷膜对再生气的水热回收特性研究[J]. 能源工程, 2020(6): 1-9.
	SONG Zenghua, FANG Mengxiang, WANG Tao, et al. Study on heat and water recovery from regeneration gas using nanoporous ceramic membrane[J]. Energy Engineering, 2020(6): 1-9.
6	WANG Tingting, YUE Maowen, QI Hong, et al. Transport membrane condenser for water and heat recovery from gaseous streams: Performance evaluation[J]. Journal of Membrane Science, 2015, 484: 10-17.
7	曹语, 王乐, 季超, 等. 陶瓷膜冷凝器用于烟气脱白烟过程的中试研究[J]. 化工学报, 2019, 70(6): 2192-2201.
	CAO Yu, WANG Le, JI Chao, et al. Pilot-scale application on dissipation of smoke plume from flue gas using ceramic membrane condensers[J]. CIESC Journal, 2019, 70(6): 2192-2201.
8	崔秋芳, 徐立强, 涂特, 等. CO₂化学吸收法中再生气的陶瓷膜余热回收特性[J]. 化工进展, 2019, 38(8): 3540-3547.
	CUI Qiufang, XU Liqiang, TU Te, et al. Waste heat recovery performance from stripping gas in CO₂ chemical absorption process by using ceramic membrane[J]. Chemical Industry and Engineering Progress, 2019, 38(8): 3540-3547.
9	KIM Kiho, YOO Myeongyeol, Kisang AHN, et al. Thermal and mechanical properties of AlN/BN-filled PVDF composite for solar cell backsheet application[J]. Ceramics International, 2015, 41(1): 179-187.
10	李欣. 聚偏氟乙烯导热性能改性研究[D]. 天津：天津大学，2013.
	LI Xin. Modification of poly(vinylidene fluoride) heat conducting property[D]. Tianjin: Tianjin University, 2013.
11	晏水平. 膜吸收和化学吸收分离CO₂特性的研究[D]. 杭州：浙江大学，2009.
	YAN Shuiping. Study on CO₂ separation characteristic by using membrane gas absorption and chemical absorption technology[D]. Hangzhou: Zhejiang University, 2009.
12	HOU Deyin, DAI Guohua, FAN Hua, et al. Effects of calcium carbonate nano-particles on the properties of PVDF/nonwoven fabric flat-sheet composite membranes for direct contact membrane distillation[J]. Desalination, 2014, 347: 25-33.
13	XU Liqiang, CUI Qiufang, TU Te, et al. Waste heat recovery from the stripped gas in carbon capture process by membrane technology: Hydrophobic and hydrophilic organic membrane cases[J].Greenhouse Gases: Science and Technology, 2020, 10(2): 421-435.
14	SOBRINO M, CONCEPCIÓN E I, GÓMEZ-HERNÁNDEZ Á, et al. Viscosity and density measurements of aqueous amines at high pressures: MDEA-water and MEA-water mixtures for CO₂ capture[J]. The Journal of Chemical Thermodynamics, 2016, 98: 231-241.
15	YAN Shuiping, CUI Qiufang, TU Te, et al. Membrane heat exchanger for novel heat recovery in carbon capture[J]. Journal of Membrane Science, 2019, 577: 60-68.
16	EFOME J E, BAGHBANZADEH M, RANA D, et al. Effects of superhydrophobic SiO₂ nanoparticles on the performance of PVDF flat sheet membranes for vacuum membrane distillation[J]. Desalination, 2015, 373: 47-57.
17	Parker TexLoc Library[EB/OL]. [2022-05-06]. .
18	曹竞一, 汪朝晖, 汪效祖, 等. 导热增强型PVDF膜及其膜冷凝过程强化[J]. 膜科学与技术, 2020, 40(2): 75-81.
	CAO Jingyi, WANG Zhaohui, WANG Xiaozu, et al. Enhancing the thermal conductivity of poly(vinylidene fluoride) membranes[J]. Membrane Science and Technology, 2020, 40(2):75-81.
19	HU H W, TANG G H, NIU D. Wettability modified nanoporous ceramic membrane for simultaneous residual heat and condensate recovery[J]. Scientific Reports, 2016, 6: 27274.
20	CHEN Haiping, YANG Boran. Experiment and simulation method to investigate the flow within porous ceramic membrane[J]. Journal of the Australian Ceramic Society, 2018, 54(3): 575-586.
21	LIN Chengxian, WANG Dexin, BAO Ainan. Numerical modeling and simulation of condensation heat transfer of a flue gas in a bundle of transport membrane tubes[J]. International Journal of Heat and Mass Transfer, 2013, 60: 41-50.
22	XIONG Yingying, TAN Houzhang, WANG Yibin, et al. Pilot-scale study on water and latent heat recovery from flue gas using fluorine plastic heat exchangers[J]. Journal of Cleaner Production, 2017, 161: 1416-1422.
23	孟庆莹, 曹语, 黄延召, 等. 过程参数对采用多孔陶瓷超滤膜回收烟气中余热和水性能的影响[J]. 化工学报, 2018, 69(6): 2519-2525.
	MENG Qingying, CAO Yu, HUANG Yanzhao, et al. Effects of process parameters on water and waste heat recovery from flue gas using ceramic ultrafiltration membranes[J]. CIESC Journal, 2018, 69(6): 2519-2525.

[1]	肖辉, 张显均, 兰治科, 王苏豪, 王盛. 液态金属绕流管束流动传热进展[J]. 化工进展, 2023, 42(S1): 10-20.
[2]	盛维武, 程永攀, 陈强, 李小婷, 魏嘉, 李琳鸽, 陈险峰. 微气泡和微液滴双强化脱硫反应器操作分析[J]. 化工进展, 2023, 42(S1): 142-147.
[3]	赵晨, 苗天泽, 张朝阳, 洪芳军, 汪大海. 负压状态窄缝通道乙二醇水溶液传热特性[J]. 化工进展, 2023, 42(S1): 148-157.
[4]	黄益平, 李婷, 郑龙云, 戚傲, 陈政霖, 史天昊, 张新宇, 郭凯, 胡猛, 倪泽雨, 刘辉, 夏苗, 主凯, 刘春江. 三级环流反应器中气液流动与传质规律[J]. 化工进展, 2023, 42(S1): 175-188.
[5]	杨寒月, 孔令真, 陈家庆, 孙欢, 宋家恺, 王思诚, 孔标. 微气泡型下向流管式气液接触器脱碳性能[J]. 化工进展, 2023, 42(S1): 197-204.
[6]	王胜岩, 邓帅, 赵睿恺. 变电吸附二氧化碳捕集技术研究进展[J]. 化工进展, 2023, 42(S1): 233-245.
[7]	陈匡胤, 李蕊兰, 童杨, 沈建华. 质子交换膜燃料电池气体扩散层结构与设计研究进展[J]. 化工进展, 2023, 42(S1): 246-259.
[8]	戴欢涛, 曹苓玉, 游新秀, 徐浩亮, 汪涛, 项玮, 张学杨. 木质素浸渍柚子皮生物炭吸附CO₂特性[J]. 化工进展, 2023, 42(S1): 356-363.
[9]	邵博识, 谭宏博. 锯齿波纹板对挥发性有机物低温脱除过程强化模拟分析[J]. 化工进展, 2023, 42(S1): 84-93.
[10]	陈林, 徐培渊, 张晓慧, 陈杰, 徐振军, 陈嘉祥, 密晓光, 冯永昌, 梅德清. 液化天然气绕管式换热器壳侧混合工质流动及传热特性[J]. 化工进展, 2023, 42(9): 4496-4503.
[11]	卜治丞, 焦波, 林海花, 孙洪源. 脉动热管计算流体力学模型与研究进展[J]. 化工进展, 2023, 42(8): 4167-4181.
[12]	汪健生, 张辉鹏, 刘雪玲, 傅煜郭, 朱剑啸. 多孔介质结构对储层内流动和换热特性的影响[J]. 化工进展, 2023, 42(8): 4212-4220.
[13]	王云刚, 焦健, 邓世丰, 赵钦新, 邵怀爽. 冷凝换热与协同脱硫性能实验分析[J]. 化工进展, 2023, 42(8): 4230-4237.
[14]	李洞, 王倩倩, 张亮, 李俊, 付乾, 朱恂, 廖强. 非水系纳米流体热再生液流电池串联堆性能特性[J]. 化工进展, 2023, 42(8): 4238-4246.
[15]	白亚迪, 邓帅, 赵睿恺, 赵力, 杨英霞. 变温吸附碳捕集机组标准化测试方案探讨及性能实验[J]. 化工进展, 2023, 42(7): 3834-3846.

CO₂捕集工艺中热再生气余热的PVDF/BN-OH平板复合膜回收特性

Recovery characteristics of PVDF/BN-OH flat composite membrane for waste heat of hot stripped gas in CO₂ capture process

RichHTML

PDF (PC)

可视化

摘要/Abstract

引用本文

使用本文

图/表 14

参考文献 23

相关文章 15

编辑推荐

Metrics

本文评价