氢系统关键氢阱最优氢浓度的确定

Optimal concentration of key hydrogen sink in hydrogen systems

氢气网络优化时一般将氢阱氢浓度降低至最低限制浓度,以获取最大可能的节氢效果,然而这会降低系统操作弹性。分析了在氢阱氢浓度降低的过程中,有可能出现夹点位置的改变,从而导致节氢量-氢阱氢浓度曲线斜率的减小以及氢气网络中要考虑的其他经济因素,提出了在氢阱氢浓度降低过程中找出最优浓度并在此浓度下进行系统优化的方法,使得氢阱氢浓度降低幅度不大但系统的节氢效果较为显著。以某炼厂为例,通过选择关键氢阱,分析该关键氢阱氢浓度与系统节氢量的关系,确定最优浓度,系统优化后节氢量为42.81mol.s-1,占现行系统新氢用量的21.58%。结果表明,该方法可在氢阱氢浓度降低较小的情况下实现较好的节氢目的。

A hydrogen network is usually optimized based on lowering the hydrogen concentration of each hydrogen sink to the lowest limit in order to obtain possibly the largest hydrogen saving.However,it may reduce the operating flexibility.During reducing the hydrogen sink concentration,the pinch location may change which leads to the slope reduction of hydrogen saving amount-hydrogen sink concentration curve.Based on such analysis as well as the other economic factors,a method to determine the optimal hydrogen concentration to optimize the system is proposed,in which way,good hydrogen saving with a marginally lower concentration in hydrogen sinks can be obtained.A case study is used to show the method,for which the optimal hydrogen concentration of a key hydrogen sink is found based on the relationship between the concentration of the key hydrogen sink and the hydrogen saving amount.The hydrogen saving amount is 42.81 mol·s-1 which accounts for 21.58% of the current fresh hydrogen consumption.The results show that this method could achieve a good effect of hydrogen saving in the case of that the hydrogen sink concentration reduces lower.