High Efficiency Heat Exchanger for Drain-Water Heat Recovery

加拿大人平均每天使用75升热水，其中一半以上用于洗澡，洗衣和洗碗。当产生的废水流入下水道时，会携带大量的热能。回收这些热能的一种方法是使用废水热回收（DWHR）系统，这是一种热交换器，在废水流入热水器之前将热量从废水转移到流入的冷水中。目前市售的DWHR系统具有相对低的热交换效率。他们也没有检测泄漏的方法，这可能导致饮用水污染。排水热回收系统需要一个泄漏检测系统，如果两股水流之间的墙壁破裂，该系统将发出警报。拟议中的项目是多伦多大学和兰开斯特住宅公司之间的合作，该公司总部位于里士满山，是安大略领先的住宅建筑商之一。 我们将设计和建造高效热交换器，以回收和利用废热水中的热能，同时还将开发安全系统，以检测灰水和淡水管线的混合情况。建议项目的主要目标是：-优化高效管壳式换热器的设计。- 设计一种用于余热回收的新型降膜式热交换器-根据ANSI标准构建两种热交换器并对其进行测试。开发一个主动泄漏检测系统，一旦灰水管线和淡水管线发生混合，立即向用户发出警报。

The average Canadian uses 75 L of hot water per day, over half of which is used for bathing, laundry, and dishwashing. When the waste water produced flows into drains it carries a significant amount of thermal energy with it. One way of recovering some of this energy is to use a drain water heat recovery (DWHR) system, which is a heat exchanger that transfers heat from wastewater to incoming cold city water before it flows into the water heater. Current DWHR systems that are commercially available have a relatively low heat exchange effectiveness. They also have no method of detecting leaks, which could potentially lead to contamination of potable water. Drain water heat recovery systems need a leak detection system that will sound an alert if the wall between the two water streams is ruptured.The proposed project is a collaboration between the University of Toronto and Lancaster Homes, which is based in Richmond Hill and is one of Ontario's leading residential builders. We will design and build high-efficiency heat exchangers to recover and use the thermal energy from waste hot water, while also developing a safety system to detect when mixing of grey and fresh water lines. The chief objectives of the proposed project are:- Optimise the design of a high-efficiency shell-and-tube heat exchanger. - Design a novel falling-film heat exchanger for waste heat recovery- Build both heat exchangers and test them according to ANSI standards.- Develop an active leak detection system, to immediately alert the user once mixing of the grey and fresh water lines occurs.