陈慧群

摘要：质子交换膜燃料电池（PEMFC）是一种随着负载变化快速响应的便携式能源，这是由于其具有能量密度高、启动迅速的特点。氢气构成了PEMFC的燃料，并可以在原位现场重整获得，以避免氢气储存、运输等过程易燃易爆安全隐患问题。一种产生氢气的有效方法是通过在微反应器中甲醇蒸汽现场重整。此吸热反应产氢最高效率发生在250°C到300°C间。因此各种不同方法用来实现和维持电加热器和化学反应所需的温度，以备它们为此吸热重整反应提供热源。文章采用一种免费的可再生能源──太阳能来提高微反应器的效率。通过在水醇混合溶液流动的微通道中涂覆有选择性材料的薄真空层，可有效隔绝微型太阳的热辐射损失和降低空气的热传导（由于该涂料具有短波长入射辐射的高吸收率和红外辐射的低发射率，可以减少热量损失）。通过发挥这些涂層的绝缘作用，在微通道中的流体温度可高于250°C，因此。该微反应器通过采用太阳辐射，比现有的常规制氢微反应器具有更高的产氢效率。

Abstract： Proton exchange membrane fuel cell （PEMFC） is a portable energy source that responds quickly to load changes， this is due to the ability to provide high power density and to start quickly. Hydrogen constitutes the fuel of the PEMFC and can be obtained by reforming， which can be avoided some security flaws such as inflammable and explosive danger in hydrogen storage process and transportation process. An effective way for hydrogen production is through methanol steam reforming in a microreactor. The highest hydrogen production rate of this endothermic reaction occurs between 250℃ and 300℃. Therefore， various methods are used to achieve and maintain the temperature needed for the electric heater and the exothermic reaction to provide the heat source for the heat absorption reforming reaction. Solar energy， which is a free renewable energy， is used to improve the efficiency of the microreactor in this paper. Microchannels， in which the water-alcohol mixed solution flows， are effectively isolated heat loss and reduce the heat conduction of the air by coating with a thin vacuum layer of selective material （Because the coating has high absorption rate of short wave length incident radiation and low emissivity of infrared radiation， the loss of heat can be reduced）. By using the insulating layer of these coatings， the temperature of the fluid in the microchannels is predicted to be higher than 250℃. Therefore， the microreactor which is using solar radiation and compared with the existing reactors， has higher hydrogen production efficiency.

关键词：太阳能集热；甲醇重整；制氢；微反应器；热模型

Key words： solar collector；methanol reforming；hydrogen production；microreactor；thermal model

中图分类号：TM911.42 文献标识码：A 文章编号：1006-4311（2018）16-0143-04

0 引言

未来的能源生产不依靠大规模污染的化石燃料及消耗性电能，而应依靠可再生和清洁的、便携式的生产方法。事实上，在这个地球上最大的、大多数还未充分利用的可再生能源资源就是太阳能，每年它输送到地球的光功率就有17.8万TW[1]。这种能源用在大型固定能源的生产中，无论是直接热能转换还是直接电力转换（光伏）都是行之有效的。……