Designation: D4929 - 17

Standard Test Method for

Determination of Organic Chloride Content in Crude  Oil

原油中有机氯化物含量测定的标准试验方法


1. Scope 范围

1.1   The procedures in this test method cover the determination of organic chloride (above 1 ug/g organically-bound chlorine) in crude oils, using either distillation and sodium biphenyl reduction, distillation and microcoulometry, or distillation and x-ray fluorescence (XRF) spectrometry.

1.2   The procedures in this test method involve the distillation of crude oil test specimens to obtain a naphtha fraction     prior to chloride determination. The chloride content of the naphtha fraction of the whole crude oil can thereby be obtained. See Section 5 regarding potential interferences.


……………


1.5   Procedure C covers the determination of organic chloride in the washed naphtha fraction of crude oil by x-ray fluorescence spectrometry.

1.1 本试验方法中的程序包括使用蒸馏和联苯钠还原、蒸馏和微库仑法或蒸馏和X射线荧光(XRF)光谱法测定原油中的有机氯化物(大于1μg/g有机结合氯)。             

1.2 本试验方法中的程序涉及蒸馏原油试样,以在氯化物测定之前获得石脑油馏分。从而可以得到整个原油石脑油馏分的氯化物含量。关于潜在干扰,见第5节。             


……………


1.5 程序C包括用X射线荧光光谱法测定原油洗涤洗石脑油馏分中的有机氯。             


……………


4. Significance and Use 意义和用途

4.1  Organic chlorides do not occur naturally in crude oil. When present, they result from contamination in some manner, such as disposal of chlorinated solvent used in many dewaxing pipeline or other equipment operations.

4.1.1   Uncontaminated crude oil will contain no detectable organic chloride, and most refineries can handle very small amounts without deleterious effects.

4.1.1.1  Most trade contracts specify that no organic chloride is present in the crude oil.

4.1.2   Several  pipelines  have  set  specification  limits  at <1 mg /kg organic chlorides in the whole crude, and <5 mg /kg in the light naphtha, on the basis of the naphtha fraction being 20 % of the original  sample.

4.1.2.1  To  ensure <1 mg /kg organic chloride in the crude   oil, the amount measured in the naphtha fraction shall be <1/f (where f is the naphtha fraction calculated with Eq 3).

4.1.3   Organic chloride present in the crude oil (for example, methylene chloride, perchloroethylene, etc.) is usually distilled into the naphtha fraction. Some compounds break down during fractionation and produce hydrochloric acid, which has a corrosive effect. Some compounds survive fractionation and     are destroyed during hydro-treating (desulfurization of the naphtha).

4.2  Other halides can also be used for dewaxing crude oil; in such cases, any organic halides will have similar impact on the refining operations as the organic  chlorides.

4.3  Organic chloride species are potentially damaging to refinery processes. Hydrochloric acid can be produced in hydrotreating or reforming reactors and the acid accumulates in condensing regions of the refinery. Unexpected concentrations of organic chlorides cannot be effectively neutralized and damage can result. Organic chlorides are not known to be    naturally present in crude oils and usually result from cleaning operations at producing sites, pipelines, or tanks. It is important for the oil industry to have common methods available for the determination of organic chlorides in crude oil, particularly    when transfer of custody is  involved.

4.1 原油中不存在天然的有机氯化物。当存在时,它们以某种方式污染造成,例如处理许多脱蜡管道或其他设备操作中使用的氯化溶剂。             

4.1.1 未受污染的原油将不含可检测的有机氯化物,大多数炼油厂可以处理非常少量的有机氯化物,而不会产生有害影响。             

4.1.1.1 大多数贸易合同规定原油中不含有有机氯化物。             

4.1.2 在石脑油组分为原始样品的20%的基础上,有几条管道规定了整个原油中<1 mg/kg和石脑油中<5 mg/kg的有机氯化物的规格限值。       

4.1.2.1 为确保原油中的有机氯化物含量<1 mg kg,石脑油中测得的含量应小于1/f(其中f是用式3计算的石脑油分数)。             

4.1.3 原油中的有机氯化物(如二氯甲烷、四氯乙烯等)通常蒸馏成石脑油馏分。有些化合物在分馏过程中分解,产生盐酸,有腐蚀作用。一些化合物在分馏过程中幸存下来,并在加氢处理(石脑油脱硫)过程中被破坏。             

4.2 其他卤化物也可用于原油脱蜡;在这种情况下,任何有机卤化物对炼油作业的影响与有机氯化物相似。             

4.3 有机氯化物对炼油过程有潜在危害。盐酸可在加氢处理或重整反应器中产生,并在炼油厂的冷凝区积聚。意外浓度的有机氯化物无法有效中和,可能造成损害。已知原油中不存在天然的有机氯化物,通常是生产现场、管道或储罐清洁作业的结果。对于石油工业来说,有共同的方法来测定原油中的有机氯化物是很重要的,特别是在涉及移交保管的情况下。


……………


 32. Precision  and Bias  精度和偏差

32.1.1  Repeatability—The difference between successive results obtained by the same operator with the same apparatus under constant operating conditions on identical test materials would, in the long run, in the normal and correct operation, exceed the following values only in one case in twenty.

32.1.1.3  Procedure C—Values can be obtained for organically-bound chlorine for any given concentration above 1 mg/kg Cl (in the original crude oil specimen) as specified in Table 2. See Table 3 for calculated values. See Note 8 for details of the ILS.

32.1.1  重复性从长期来看,在正常和正确的操作中,同一操作员在相同的试验材料上使用相同的仪器在恒定操作条件下获得的连续结果之间的差异仅在二十分之一的情况下超过下列值。

32.1.1.3  程序C—如表2所示,任何给定浓度超过1 mg/kg Cl(在原始原油样品中)时,可获得有机结合氯的值。计算值见表3ILS详情见注8   

32.1.2  Reproducibility—The difference between two single and independent results obtained by different operators working in different laboratories on identical material would, in the long run, exceed the following values only in one case in twenty.

32.1.2.1  Procedure C—Values can be obtained for organically-bound chlorine for any given concentration above  1 mg/kg Cl (in the original crude oil specimen) as specified in Table  2. See Table  3 for calculated values. See Note 8 for    details of the ILS.

32.1.2  再现性从长远来看,在不同实验室工作的不同操作员在相同材料上获得的两个单独和独立结果之间的差异在二十分之一的情况下仅会超过以下值。

32.1.2.1 程序C—如表2所示,任何给定浓度超过1 mg/kg Cl(在原始原油样品中)时,可获得有机结合氯的值计算值见表3ILS详情见注8


TABLE 2 Precision Equations, Procedure C XRF

2  精密方程式,程序C XRF

Repeatability  r, mg/kgA

MWDXRF               r = 0.643*X0.44                (19)

MEDXRF                r =  0.591*X0.44              (20)

EDXRF                r =  0.934X  + 0.40.48    (21)

Reproducibility R, mg/kgA

MWDXRF              R= 1.235*X0.44                (22)

MEDXRF               R = 1.500*X0.44               (23)

EDXRFB             R =  2.000X  + 0.40.48              (24)

AWhere X = mg/kg chloride

A式中 x=mg/kg氯化物


TABLE 3 Calculated Precision Values, Procedure C XRF

3  计算精度值,程序C XRF

Cl

Repeatability r, mg/kgA

Reproducibility R, mg/kgB

mg/kg

MWDXRF

MEDXRF

EDXRF

MWDXRF

MEDXRF

EDXRF

1

0.6

0.6

1.1

1.2

1.5

2.4

2

0.9

0.8

1.4

1.7

2.0

3.0

3

1.0

1.0

1.7

2.0

2.4

3.6

4

1.2

1.1

1.9

2.3

2.8

4.1

5

1.3

1.2

2.1

2.5

3.0

4.5

6

1.4

1.3

2.3

2.7

3.3

4.9

8

1.6

1.5

2.6

3.1

3.7

5.6

10

1.8

1.6

2.9

3.4

4.1

6.2

12

1.9

1.8

3.1

3.7

4.5

6.7

AValues calculated from Eq 19 for MWDXRF, Eq 20 for MEDXRF, and Eq 21 for EDXRF.

BValues calculated from Eq 22 for MWDXRF, Eq 23 for MEDXRF, and Eq 24 for EDXRF.


...................................................


查看更多内容,请下载文档。