What is flare knock out drum?

A flare knockout drum is a vessel in the flare header that is designed to remove and accumulate the liquids that are condensed from the relief gases. It is also known as a vapour-liquid separator or knock-out pot and is available in vertical and horizontal configurations.

What does a knock out drum do?

A Knock-out (KO) drum consists of a vertical vessel specially designed to separate vapor and liquid from a two-phase process flow. Inside you’ll find an inlet diffuser and de-entrainment mesh pad designed to maximize the collection of liquid contained in the vapor as it travels to the top of the vessel.

What is a fuel gas knockout drum?

Fuel Gas Scrubber or Knock-out (KO) drum or mist eliminators are used to remove the entrained liquid droplets and slugs from vapor stream. It assists in removing free liquids present with incoming gas and helps prevent overloading of downstream final filter elements.

How do you size a knockout drum?

Use a vertical pressure vessel with a length-to-diameter ratio of about 3 to 4, and size the vessel to provide about 5 minutes of liquid inventory between the normal liquid level and the bottom of the vessel (with the normal liquid level being at about the vessel’s half-full level).

What is the difference between separator and knock out drum?

Drum: or knock out drum (KOD) is used when a small amounts of liquid droplets to be removed gas/vapor upstream. Separator: separator is used when there is a quite a bit of liquid to be removed from gas/vapor upstream prior to delivering to the compressor suction.

How does a flare system work?

During flaring, excess gases are combined with steam and/or air, and burnt off in the flare system to produce water vapour and carbon dioxide. The process of burning these excess gases is similar to the burning of liquefied petroleum gases (LPG), which some of us use as fuel for home cooking.

Why do flash drums have a mesh pad?

A mesh pad in the upper part of the vessel aids separation and prevents liquid from being carried over with the vapor. The pad or mist mat traps entrained liquid droplets and allows them to coalesce until they are large enough to fall through the up-flowing vapor to the bottom of the vessel.

Is a separator?

Separator is a vessel used to separate gas and liquid components from the fluids extracted from an oil well. Oil, gas or water can be removed from the fluids. It can also be defined as a device which separates a fluid into its constituent components.

How does a flash drum work?

A liquid stream containing several components is partially vaporised in a ”flash drum” at a certain pressure and temperature. Because of the large drop in pressure, part of the fluid vaporizes. The vapor is taken off overhead, while the liquid drains to the bottom of the drum, where it is withdrawn.

Why is flaring bad?

What’s wrong with flaring? Plenty: Flaring releases methane, a greenhouse gas that, when released directly into the air, traps heat in the atmosphere. The process of flaring contributes directly to global warming.

Why do refineries burn off gas?

Flares are important safety devices used in refineries and petrochemical facilities. They safely burn excess hydrocarbon gases which cannot be recovered or recycled. During flaring, excess gases are combined with steam and/or air, and burnt off in the flare system to produce water vapour and carbon dioxide.

How do you separate liquid from vapor?

Distillation is an effective method to separate mixtures comprised of two or more pure liquids. Distillation is a purification process where the components of a liquid mixture are vaporized and then condensed and isolated.

Where are the knock out drums on a flare?

Flare Knockout Drums Working Animation. Knock out vessels are used to slow down gasses and allow liquids to “fall out” of the gas stream. Knock out drums can be installed either in the waste gas header, or in the flare stack base itself.

How does baffles work on a flare knockout drum?

While spinning the fluidic friction of the gas along the wall will “scrub out” much of the entrained liquid. Baffles are also used in a vertical drum to disrupt and slow down the gas prior to exit. Again these drums must be equipped with a liquid level gauge or indicator so they can be drained.

Is the Leistritz flare knock out pump replaceable?

The Leistritz Flare Knock-out pump is a timed twin-screw pump with replaceable liner, integral shafts and external bearings. The design and material composition are suitable for pumping materials that can be corrosive, abrasive or flammable.

How to calculate flare Ko drum liquid holdup?

That is: Flare KO Drum Liquid Holdup Volume = 30 Minute* [Liquid Inlet – Liquid Outlet (pump capacity) ], which made our KO Drum much smaller than based on the equation Flare KO Drum Liquid Holdup Volume = 30 Minute*Liquid Inlet. In my view there is one and possibly two reasons why you cannot take credit for the flare drum pump running.