The chemical equilibrium of gasification systems is modeled using one of two approaches, the stoichiometric (S) or the non-stoichiometric (NS) method. A complete survey of the gasification literature shows that about half of equilibrium modeling studies use either just the S, or just the NS method, and do not consider whether a different model choice would lead to a different solution. The remaining half of equilibrium modeling studies does motivate their model choice. Among those that discuss their model choice roughly half (15/27) state that the two approaches produce identical solutions. The remaining half propose that the NS method yields superior results (10/27), or the S method may yield superior results (2/27), and thus imply that the methods are not necessarily equivalent. The contradictory conjectures on both sides are made without definitive proof, or reference to definitive proof or evidence. In addition to providing a concise technical review of this question and its role in biomass gasification modeling, a second goal of this technical review article is to provide a tractable, yet rigorous and definitive exposition of the mathematical proof that the stoichiometric and non-stoichiometric approaches are equivalent methods for computing the equilibrium composition of the core gasification problem. This should provide perspective on the existing literature, and helpful guidance for future modeling work. Although the technical review and analysis provided here settles a longstanding contradiction in the gasification literature the relevant proof applies to any reactive system. The systematic template for S vs NS equivalence provided here should therefore be equally useful to researchers modeling and simulating the equilibrium of any other reactive system, since there is always the need to choose between the S or NS approach.

气化系统的化学平衡是使用化学计量（S）法或非化学计量（NS）法两种方法之一进行建模的。对气化文献的完整调查显示，大约一半的平衡建模研究仅使用S方法或仅使用NS方法，并且没有考虑不同的模型选择是否会导致不同的解决方案。平衡建模研究的其余一半确实会激发他们的模型选择。在讨论他们的模型选择的那些人中，大约一半（15/27）指出这两种方法产生相同的解决方案。其余一半建议使用NS方法可获得更好的结果（10/27），或者使用S方法可获得更好的结果（2/27），因此暗示这些方法不一定等效。双方的矛盾猜想都没有确定的证据，也没有参考确定的证据。除了对该问题及其在生物质气化模型中的作用进行简要的技术综述之外，本技术综述文章的第二个目标是提供对化学计量学和非化学计量学方法的数学证明的易处理，严格而明确的阐述。是计算核心气化问题平衡组成的等效方法。这应该提供对现有文献的观点，并为将来的建模工作提供有益的指导。尽管此处提供的技术评论和分析解决了气化文献中的长期矛盾，但相关证据适用于任何反应系统。