Thursday, 1 November 2018

Activated Carbon in Oil and Gas Refineries

The versatility of activated carbon allows its application in a variety of processes. Not only can activated carbon provide an increasingly important role in water purification, cleaning contaminated water before emission to the environment, also it can provide an extremely important economic contribution to the operations of oil and gas refineries. By assisting in the recovery of a range of expensive process chemicals, activated carbon can have a direct impact on the cost of refinery operations.

In many cases, processing operations are located close to the primary extraction point of the refinery feedstock, and the concentration of the world’s oil and gas resource in the most areas of the world means that management of water is a critical subject. Condensing steam provides an easily recovered resource, however, the criticality of the quality of the recirculated water demands the use of high purity specialized activated carbons. Where the resulting product is used for produced or potable water applications, activated carbon can assist in the achievement of extremely high purity products.

With its high adsorption capacities ranging from odorous compounds to dark colored bodies activated carbon is an excellent option for the purification of raw materials, intermediates and end products in oil and gas industry. By removing unwanted contaminants like mercury, colors, sulfur components and odors allows for the consistent production of high quality natural gas, oil and other petrochemical products. Activated carbon plays a vital role here by cleaning gas scrubber liquids, decolorizing field condensates and providing catalyst support for hydrocarbon sweetening.

In gas scrubber system activated carbon cleans the gas scrubber liquids like amines, glycols which are used in the gas absorption systems for the removal of sour gases (carbon dioxide and hydrogen sulfide) and water vapor from natural gas.
Due to the high removal efficiency, low pressure drop and high hardness of activated carbon it finds its superior application for the removal of mercury (in natural gas) which is very harmful to the environment.

Activated carbon is also used in Pressure Swing Adsorption (PSA) technology where the separation of gases is done by adsorption and desorption at different pressures. Specially developed activated carbon (GAC) is being used as catalyst carriers for hydrocarbon sweetening and this process involves the catalytic extraction of mercaptans from refinery products.

Activated carbon also finds it’s application in field condensate purification where heavier hydrocarbons and other colored bodies are removed. Due to its high adsorption and low leachable silica content properties of it is used for the removal of dissolved organic compounds like mineral oil in steam condensates generated from steam boilers. It is statutory that airborne emissions of harmful or odorous components and other contaminants from industrial process gases to be restricted to a minimum as per the norms. Activated carbon is very much cost effective in meeting these challenges and removing organic and inorganic impurities at levels up to a few hundred ppm.