Heat storage medium, esp. for dynamic heat storage system - comprising water, sodium hydroxide in concn. above the stoichiometric mono:hydrate, concn., and opt. tellurium di:oxide

摘要

A heat storage system comprises NaOH and water, the NaOH concn. being greater than the stoichiometric concn. in sodium hydroxide monohydrate and up to 80 wt.%. The pref. system comprises 70-74 wt.% NaOH and 30-26 wt.% water and 0.1-2.0 wt.% (pref. 0.1-0.5 wt.%) tellurium oxide may also be present. This system displays very little supercooling (max. 3C deg.) after the first few cycles. Addition of Te dioxide virtually eliminates supercooling during this initial 'ageing' period, and by the time the Te dioxide has dissolved and become ineffective the supercooling has been limited due to the ageing of the system. The system is esp. suitable for heat storage using an intermediate heat transfer medium which contacts the medium directly.