MarkESmith
Chemical
- Jan 19, 2011
- 9
I am a very inexperienced engineer working on an offshore gas platform design and need help using IP15 to assign Hazardous Area Classifications to a sand bin as part of a Produced Water management system.
Basically we have proposed vented bins be used to store sand emptied from a Sand Accumulator serving a Produced Water Desander. This Accumulator will be filled with sand that has water and trace amounts of condensate (approximately 5 vol % cond. in the produced water) in it. The Accumulator is emptied up to once a day (but usually every 3-4 days) into the bins which sit there a few days before being removed. Some vapour will be evolved due to the pressure drop between the 6000 kPaa Accumulator and the atmospheric sand bin.
I am unsure as to whether to classify the bins as a Primary Grade release or a Continuous Grade release as per Section 1.6 of IP15. The argument for Continuous I guess is that the sand is frequently present in the containers, presenting a “continuous or nearly so” source of hydrocarbons venting to atmosphere. The argument for Primary is I guess that whatever hydrocarbon fractions that flash off at atmospheric pressure will do so quickly (but I may be wrong in thinking this), thus presenting more of a “periodic or occasional” release than a continuous one. However, I see that Section 1.6.4 of IP15 states that “The grade of release is dependent solely on the frequency and duration of the release” and “independent of the rate and quantity of the release”, lending support to a Continuous Grade classification.
Can anyone familiar with IP15 offer me any opinion on whether Continuous or Primary is the more appropriate grade of release?
Basically we have proposed vented bins be used to store sand emptied from a Sand Accumulator serving a Produced Water Desander. This Accumulator will be filled with sand that has water and trace amounts of condensate (approximately 5 vol % cond. in the produced water) in it. The Accumulator is emptied up to once a day (but usually every 3-4 days) into the bins which sit there a few days before being removed. Some vapour will be evolved due to the pressure drop between the 6000 kPaa Accumulator and the atmospheric sand bin.
I am unsure as to whether to classify the bins as a Primary Grade release or a Continuous Grade release as per Section 1.6 of IP15. The argument for Continuous I guess is that the sand is frequently present in the containers, presenting a “continuous or nearly so” source of hydrocarbons venting to atmosphere. The argument for Primary is I guess that whatever hydrocarbon fractions that flash off at atmospheric pressure will do so quickly (but I may be wrong in thinking this), thus presenting more of a “periodic or occasional” release than a continuous one. However, I see that Section 1.6.4 of IP15 states that “The grade of release is dependent solely on the frequency and duration of the release” and “independent of the rate and quantity of the release”, lending support to a Continuous Grade classification.
Can anyone familiar with IP15 offer me any opinion on whether Continuous or Primary is the more appropriate grade of release?