1.11.003 Coalescing Elements in Discharge/Receiver Vessels

This Policy is completed waiting Field Service, Engineering, and EHSS approval.

Purpose

The purpose of this procedure is to establish the minimum requirements for understanding the basics of how the Discharge/Receiver vessel Coalescing/Receiver Element functions on Flogistix FX model units. The procedure applies to all Flogistix FX model units equipped with a Discharge/Receiver vessel with a Coalescing/Receiver element installed.

Procedure

This procedure applies to all Flogistix FX model units that are equipped with a Discharge/Receiver vessel that has a Coalescing element installed and is currently in service in the Field, Test Loop, at a Repair Shop, or in Storage Yards.

Flogistix uses what is called a Top Hat design coalescing element, based on its shape.

The Top Hat design is open on one end and is closed on the other with a wide flat ring with gaskets on each side of the open end, similar to the old top hats like President Lincoln famously wore.

Examples of a Top Hat design Coalescing element

Be aware that Inlet filters look very similar to discharge coalescing elements.

Most discharge elements will have a dished end cap as the example below.

Most Inlet Filters will have a flat end cap as in the example below

Do not always count on this.

If an inlet filter is mistakenly installed in a discharge vessel, compressor oil loss will occur.

Discharge coalescing elements will have two grounding staples on each side of the flat ring gaskets.

(See Example Arrows)

Do not remove these staples.

This helps to prevent static electricity in the receiver element during operation.

With the grounding staples removed there could be the potential for an internal fire in the vessel

Here is an example of what happened when the discharge filter did not have grounding staples.

The mixture of gas and air has to be correct and with an ignition source it can ignite. In this case the static electricity from the discharge element was the ignition source.

When the gas starts to enter or penetrate the coalescing element (as in the example below) the larger droplets of oil that were traveling or suspended with the gas will run down the outside of the coalescing element.

The fine oil vapor that is remaining with the gas will begin to penetrate the media that the coalescing element is made of.

As the gas flows through the media, the media will start to collect the oil mist and converts it into larger droplets.

The remaining oil droplets will then flow to the inside opening of the element and will run down the side of the coalescing element. It will then pool at the bottom of the element.

The pooled oil in the bottom of the receiver element is then returned to the compressor oil system via the scavenging line.

For Scavenge Line operation reference refer to Field Service Wiki procedure 1.6.02 or the attached link: 1.6. 2 Scavenge Line Adjustment

The scavenging line is connected to the suction or inlet of the screw compressor.

The gas that has passed through the coalescing element will then exit out the top of the discharge vessel.

When the coalescing element and scavenging line is working properly, there should be very little oil carryover in the gas. This amount should be measured in parts per million

A simple way to explain how a coalescing element works is a lot like putting water in a spray bottle.

Then spray the water at a window screen. Most of the water will stay on the outside or the bottle side of the screen and run down.

Some of the water will penetrate the screen and will run down the other side of the screen.

This is a lot like how a coalescing element works with compressor oil.

The coalescing element has a micron rating of 0.3 microns. (For reference, a red blood cell is approximately 8 microns in size and a human hair is about 50 microns in diameter).

Coalescing element Failures:

If the coalescing element starts to plug up it can cause high differential pressure across the element. When the differential pressure gets too high across the element it can cause the element to collapse.

When the coalescing element starts to partially plug up it will create the same effect as having a smaller surface area of the media. If the surface area of the media is too small it can cause oil loss.

Blowing the unit down too fast can cause oil carry over.

When doing this the gas volume across the discharge element is greater than what the element is designed for.

A sudden drop in discharge pressure can cause the coalescing element to loose efficiency and carry oil over. If the discharge pressure is inconsistent and goes up and down it could cause oil loss,

A sudden rapid drop in pressure across the element could cause the element to collapse or partially collapse, This will lead to oil loss in the vessel.

Responsibilities

Management - Management is responsible for implementing, supporting, and enforcing the requirements of this procedure to their respective locations/area.

EHSS - Responsible to assist in the implementation of this procedure and to review for effectiveness.

Employees, Contractors, Vendors, ETC. - Are responsible to follow the requirements outlined in this procedure and ask for assistance

Scope

This procedure applies to all Flogistix FX model Discharge/Receiver vessel with a Coalescing element installed and are applicable to all Flogistix employees, contractors, and temporary employees.

Hazards

Employees should be aware that units could contain flammable and toxic gasses. Potential for the possible hazards of gas ignition or fire, hot surfaces & fluids, rotating equipment. Risk of possible concentration of H2S. Hazardous gases could be in the units pressure vessels, cooler, or associated piping and risk of inhalation of hazardous gas fumes.

Safety

All Personal Protective Equipment (PPE) for normal Field Mechanical duties apply for this procedure.

Four Gas Monitor, which is outlined in the Flogistix EHSS Manual, PPE Section 8, Procedure 8.3

This procedure applies to all units in service in the field, at a service shop, or in any storage yard.

Insure Flogistix personnel have proper safety certification or site orientation if required by the Flogistix Customer.

Insure Flogistix personnel adhere to all Customers safety practices.

Training

All employees shall be initially trained on the following topics:

• Employee Personal Protective Equipment (PPE)

• Lock Out Tag Out (LOTO) procedure according to Flogistix policy

• Emergency and First Aid procedures

• Methods and Observations that may be used to detect the presence or release of a hazardous chemicals or gas in the work place

Tools & Equipment Required

All employees performing this procedure shall be required to have the listed tools to perform job tasks:

• All required PPE according to Flogistix Safety Policy

Approvals

Field Service approved by:

Date:

Engineering approved by:

Date:

EHSS approved by:

Date: