Specific gravity

Common symbols	SG
SI unit	Unitless
Derivations from other quantities

 

 

The reference substance is nearly always water at its densest (4°C) for liquids; for gases it is air at room temperature (21°C).

 

Nonetheless, the temperature and pressure must be specified for both the sample and the reference. Pressure is nearly always 1 atm (101.325 kPa).

About Pseudocomponents(ASPEN Plus)

1. Pseudocomponents(ASSAY)

Pseudocomponents represent fractions of a petroleum mixture within specified ranges of true boiling point (TBP). You can enter cut point temperatures to specify these ranges, or use the default cut points. ADA/PCS cuts the TBP distillation curve at these temperatures to determine the proportions of the pseudocomponents. Material which boils at temperatures above the highest cut point is included in the highest-temperature pseudocomponent. Material which boils at temperatures below the lowest cut point is included in the lowest temperature cut point, except for specific components specified as light ends. (See About Light Ends.) Pseudocomponents are not created for cutpoint temperatures outside the range of the distillation curve data unless All is selected for the Pseudocomponent generation option on the Components | Petro Characterization | Generation | Cuts sheet.

ADA/PCS determines the normal boiling point of each pseudocomponent by integrating the distillation curve to produce a volume-fraction or weight-fraction average boilingpoint (depending on the basis of the entered distillation curve).

2. Pseudocomponents(User-defined)

You can also create user-defined pseudocomponents on the Components | Specifications | Selection sheet. Rather than being generated from assay data, thesepseudocomponents are characterized by the data you enter on the Components | Pseudocomponents form.

You must enter two of the following types of data for each user-defined pseudocomponent:

• Molecular weight

• Normal boiling temperature

• Specific gravity or API gravity

LNG 수급동향 (2016.4.1 )

• 유가하락과 공급과잉으로 최근 아.태지역의 LNG 교역가격이 큰 폭으로 하락
• 신규공급이 증가(미국,호주) + 기존 설비가 안정적으로 가동함에따라 공급량이 증가 + 동북아지역의 수요 감소 --> LNG 공급과잉
• 잉여물량 --> 유럽으로 유입 --> 현물 가스 가격 압박 예상

공급

호주: 2개의 CBM 액화프로젝트 공급개시, 2016.03 고곤 프로젝트 LNG 수출 시작

미국: 2016년중 사빈 패스 프로젝트 2 train 생산 개시

수요

동북아(-711만톤), 미주지역(-200만톤) 수요감소

MENA(Middle East, North Africa)지역 수요 증가(+620만톤)