What are the requirements for an incinerator / incinerator package or thermal oxidizer in a hazardous area classified zones such as oil and gas drilling sites? How are these fields classified?

Classified hazardous areas are defined as "any place in which an explosive atmosphere may occur in quantities such as to require special precautions to protect the safety of workers".

Hazardous areas are classified into zones based on an assessment of the frequency of the occurrence and duration of an explosive gas atmosphere, as follows:

•             Zone 0: Where an explosive gas atmosphere is present continuously or for long periods;

•             Zone 1: Where an explosive gas atmosphere is likely to occur in normal operation;

•             Zone 2: Where an explosive gas atmosphere is not likely to occur in normal operation and, if it occurs, will only exist for a short time.

The equipment working in these hazardous conditions also have to meet certain safety standards such as explosion-proof construction, to prevent danger to men, materials and machines.

The starting point is to identify sources of release of flammable gas or vapour and mark them as `hazardous areas`. When the hazardous areas of a plant have been classified, the remainder will be defined as non-hazardous, sometimes referred to as 'safe areas'.

The equipment categories are defined by the ATEX equipment directive, set out as the Equipment and Protective Systems for Use in Potentially Explosive Atmospheres Regulations 1996. Most electrical standards have been developed over many years and are now set at international level, while standards for non-electrical equipment are only just becoming available.

There are different concepts when it comes to building equipment to meet different categories giving the type or required protection such as:

Category 1:

Zone 0 - `ia` intrinsically safe

                `Ex s` - Special protection if specifically certified for Zone 0

Category 2:

Zone 1 - `d` flame proof enclosure

                `p` pressurized

                `q` powder filling

                `o` oil immersion

                `e` increased safety

                `ib` intrinsic safety

                `m` encapsulation

                `s` special protection

Category 3:

`en` Electrical and non-electrical

If one looks at equipment, say an electrical control panel, to make it conform to the safety requirements, the casing of each cubicle has to be made of cast aluminium of minimum 13 mm thick. 

Similarly, motors, instruments and electrical equipment must strictly conform to these standards.

We have integrated all these equipment into our incinerator system and supplied our incinerator packages for different types of wastes such as hydrocarbon condensate, waste off gases, general garbage, etc. to a number of oil & gas installations throughout the world.

In India, our incinerator equipment are working, on the one hand, at the onshore terminal of a deep sea oil and gas drilling site where drilling takes place at 4000 metres below the sea bed, and on the other, in a northern desert at scorching heat.

You will find Haat’s incinerators at work in many oil and gas fields in Middle Eastern countries such as Yemen, Iraq, Iran and in an Eastern country like Myanmar.

More on Haat's incinerator package here - Model SRD

Some reference projects - Reliance Industries Limited