pro2热力学方法的选用

2024年1月7日发(作者：二十万左右的车推荐)

PROⅡ热力学方法的选用

ProⅡ热力学最少输入：对于只进行热平衡、物料平衡计算最少输入SYSTEM=SRK，传递物性是不需要的。

每一个不同的SYSTEM关键词均包括K值、气液相焓值、熵值、气液相密度计算方法，但不同的关键词具体每一种性质计算方法参传递性质：见ProⅡ输入手册。

传递性质：Transport关键词，决定传递性质的计算方法，包括汽液相粘度、汽液相导热系统、表面张力，严格换热计算、塔板水学计算传递物性总是必需的。

体系性质：模拟计算之前，必须知道系统所有组分，及形成什么样的体系，强极性还是弱极性。体系所处的温度、压力范围。

水的考虑：体系内是否有水？水是做严格第二相，还是作为近似处理？作为近似处理可用一般的热力学方法。作为严格第二相处理，必须使用适于两液相热力学方法。

热力学的选用是模拟成功第一因素。

与实际吻合的热力学是最好的热力学，因此有准确的实验数据或工程实际数据时，应筛选计算结果与实际数据吻合的热力学。

应尽量选用最简单、最适用的热力学。

通用关联式或状态方程无法用于极性体系。

选用热力学时考虑体系主体，而不应重点考虑微量组分，否则计算结果反与实际不符。

炼油和气体工艺的应用：

水的考虑：用简单的烃热力学方法的缺省水倾析相完全可满足要求。例：SRK、PR、GS、BK10，BWRS,CS,CSE,GSE,IGS。

低压原油系统（常减压塔）：BK10，GS/IGS，SRK/PR。

高压原油系统（FCCU主分馏塔、COKER主分馏塔）：GS，SRK/PR

重整和加氢系统：SRK/PR用API计算液相密度。

润滑油和溶剂油沥青系统：SRK/P，SRKM。

天然气系统：

— SRK/PR/BWRS 对于大部分烃和水烃系。

— SRKKD 对于水烃高压系统，不包含极性组分。

— SRKM/PRM 包含水和其他极性组分，严格两相。

— SRKP/PRP 包含水和其他极性组分，严格两相。

乙二醇干燥系统：GLYCOL

酸水系统：SOUR（酸性气体H2S,CO2,NH3总重量小于0.3）、

GPSWAT（比SOUR范围大，增加了CO,CS2,COS,MESH,ETSH等组份）

胺系统：AMINE（都有其特定的温度压力范围，混合胺不能计算）

石油化工的应用：

轻烃系统

— SRK/PR/BWRS为纯水相，用COSTALD计算液相密度。

— SRKKD为严格第二相，用COSTALD计算液相密度。

芳烃系统

— LIBRARY 低压下适用。

— GS/SRK/PR 高压下适用。

芳烃/非芳系统

— SRKM/PRM/SRKH/PRH

— NRTL/UNIFAC抽提系统，用Henry选项模拟少量超临界气体，用UNIFAC FILL选项计算缺少的二元参数。

非烃系统（烃的氧、卤素或氮的衍生物）

— Wilson用HENRY和UNIFAC FILL选项，不能用于两液相系统。

— NRTL/UNIQUAC用HENRY和UNIFAC选项，可用于两液相系统。

— SRKH/PRH/SRKM/PRM对高压或大量超临界气体系统，单液相和两液相均可用。

— SRKP/PRP对高压或大量非重要气体系统，单液相和两液相均可用，结果不如上条。

乙醇脱水系统

— ALCOHOL

— NRTL/UNIQUAC必须用户提供有效的相互作用参数。

化学方面的应用

非离子系统

— WILSON轻度非理想系统，用HENRY选项，不能用于两液相系统。

— NRTL/UNIQUAC非理想系统用HENRY和UNIFAC FILL选项，可用于两液相系统。

— SRKH/PRH/SRKM/PRM对高压或大量非重要气体系统，单液相和两液相均可用。

— SRKP/PRP对高压或大量非重要气体系统，单液相和两液相均可用，结果不如上条。

羧酸系统

用液相活度系数方法，气相性质用HOCV方法计算。

固体系统

固液平衡用van\'t Hoff理想溶液方法。

固体应用

Solid-liquid equilibria for most systems can be represented by the van\'t Hoff

(ideal) solubility method or by using user-supplied solubility data. In general, for

those systems where the solute and solvent components are chemically similar

and form a near ideal solution, the van\'t Hoff method is appropriate. For

non-ideal systems, solubility data should be supplied. For most organic crystalli-zation systems, which are very near ideal in behavior, the van\'t Hoff SLE method

provides good results. The VLE behavior can usually be adequately represented

by IDEAL or VANLAAR methods.

General Information

The Curl-Pitzer method calculates enthalpies and entropies. It is generally useful for refinery

hydrocarbons Refer to the PRO/II Reference Manual for additional limitations.

General Information

The Lee-Kesler method calculates enthalpies, entropies and densities. It is generally useful for

refinery hydrocarbons. The liquid density method is not recommended for hydrocarbons

heavier than C8. Refer to the PRO/II Reference Manual for additional limitations.

Suggested application ranges

Composition - C8 & lighter (for liquid density method)

General Information

The Johnson-Grayson method calculates enthalpies. It is generally useful for heavy refinery

hydrocarbons. When using the Johnson-Grayson enthalpy method, it is recommended that the

Johnson-Grayson method be used for both liquid and vapor to the PRO/II

Reference Manual for additional limitations.

General Information

The API method calculates liquid densities. It is generally useful for refinery hydrocarbons.

Refer to the PRO/II Reference Manual for additional limitations.

The API method works well for most hydrocarbon systems, provided that the reduced

temperature is less than 1.0.

General Information

The RACKETT method calculates liquid densities. It is generally useful for refinery

hydrocarbons as well as non-hydrocarbons. Refer to the PRO/II Reference Manual for

additional limitations.

General Information

The COSTALD method calculates liquid densities. It is generally useful for aromatics and

other light refinery hydrocarbons up to reduced temperatures of 0.95. Refer to the PRO/II

Reference Manual for additional limitations.

General Information

The LKP method is derived from a corresponding states approach combined with the BWRS

equation of state (see “Benedict-Webb-Rubin-Starling” on page 4-33). The LKP method

predicts K-values, enthalpies, entropies, and vapor and liquid densities. It is most often used

for light hydrocarbons and for reformer systems containing high quantities of hydrogen.

VLLE behavior can also be predicted with the LKP method.

General Information

The HOCV method predicts vapor fugacities, vapor enthalpies, vapor entropies and vapor

densities. It is especially useful for systems where dimers form in the vapor phase, e.g.,

carboxylic acid systems. A liquid activity method must be used in conjunction with the

HOCV method.

General Information

The TVIRIAL method predicts vapor fugacities. It is useful for systems where dimers form in

the vapor phase, e.g., carboxylic acid systems. A liquid activity method must be used in

conjunction with the TVIRIAL method.

General Information

The IDIMER method predicts vapor fugacities, vapor enthalpies, vapor entropies and vapor

densities. It is especially useful for systems where dimers form in the vapor phase, e.g.,

carboxylic acid systems. A liquid activity method must be used in conjunction with the

IDIMER method.

General Information

The Redlich-Kister and Gamma heat of mixing methods apply a correction to IDEAL

enthalpy data. A liquid activity method must be used in conjunction with the Redlich-Kister or

Gamma methods.

General Information

The VANTHOFF solubility method is used to calculate solid-liquid equilibrium K-values for

nearly ideal non-electrolyte systems using the van\'t Hoff ideal solubility equation.

General Information

The TRANSPORT keyword is used to provide transport properties, including liquid and

vapor viscosities, liquid and vapor thermal conductivities, and liquid surface tension values.

Liquid diffusivities may be computed by selecting the DIFFUSIVITY(L) keyword.

TRANSPORT

This keyword selects the method used for calculation of transport properties including liquid

and vapor viscosities, liquid and vapor thermal conductivities and liquid surface tension

values. If the TRANSPORT keyword is absent, the default is that no transport method is

selected. If the TRANSPORT keyword is present, the available options are:

NONE

PURE

Suppresses all calculations of transport properties

This option applies simple mixing rules to the temperature-dependent pure

component values available in the selected databanks to calculate mixture

transport properties. Saturation values are used and no pressure corrections

apply. This method is the default if only the TRANSPORT keyword is present.

PETRO This option uses predictive correlations that apply to bulk hydrocarbon

mixtures. Pressure corrections apply.

This option uses a one fluid conformal TRAPP model to calculate vapor and

liquid viscosities and thermal conductivities for hydrocarbons. The PETRO

method is used to calculate surface tension.

This option uses the Lohrenz-Bray-Clark (LBC) liquid viscosity method, the

TRAPP conductivity methods, and the PARACHOR surface tension method.

An improved version of the PURE methods (above). Includes methods for vapor

and liquid conductivities and viscosities, but not for surface tension or

diffusivity. Refer to the Reference Manual, Volume 1, chapter 8, for more

information.

TRAPP

TACITE

SATD