Compressors are heart 

of natural gas 

production

By Norm Shade Published: August 6, 2014 2:30PM 

With the development of the Utica Shale, more and 

more natural gas compressors are appearing on the 

Eastern Ohio landscape. Gas compressors have 

always been part of Ohio’s oil and gas production, however, the size of the Utica play requires more 

and larger compressors than ever before.

Raw natural gas is commonly collected from a group of adjacent wells and, after processing at the 

collection point to remove water and natural gas condensate, it is pipelined to a gas processing plant. 

After further processing to remove salable liquid hydrocarbons (ethane, propane, butane, etc.), the 

natural gas is then delivered into the interstate pipeline grid, which takes it to commercial, industrial 

and residential customers. 

Natural gas compressors are literally the heart of natural gas production. Shale gas wells tend to 

produce at very high pressures and flow rates initially, but they decline rapidly to a lower level that is 

sustained for many years. As the pressure declines, gas compressors must be deployed to boost the 

gas pressure high enough to push it through pipelines to market. Just as the heart is vital to collecting 

and pumping blood throughout the body, a gas compressor collects natural gas from underground 

wells and “pumps” it to market.

Gas compressors are prevalent throughout the interstate pipeline grid and in gas processing plants, 

strategically located in a limited number of centralized plants. But upstream of those plants are many 

more “gathering” compressors, located at or near the actual wells that produce gas from deep 

underground. Gathering compressors typically sit out in the open, not housed in buildings. They pull 

gas from individual or a group of wells and boost the pressure to push it into a gathering pipeline that 

leads to various types of processing facilities.

Most natural gas compressors are reciprocating (i.e., piston-type) compressors, driven by 

reciprocating engines that use natural gas fuel. Much larger than the average 110 to 150 horsepower 

automobile engine or even a 450 horsepower semi-truck engine, turbocharged compressor engines are 

typically more than 1000 to as high as 4500 horsepower or even larger. Engine exhaust is quieted by a 

large industrial muffler, and to meet environmental regulatory requirements, exhaust is treated with a 

catalytic convertor, just as automotive engines are. 

Large industrial gas compressors have two to six cylinders with internal pistons and check valves. 

Connected into a pipeline, a compressor draws gas in at a low pressure and delivers it out again at a 

higher pressure to move it through the pipeline system. Depending on the needs of the particular 

gathering system, the cylinders on a compressor may be configured to operate in parallel or in series 

(called staging). Most gas gathering compressors are configured in two- or three-stages. 

10/28/2014

http://www.gasandoilmag.com/gas%20&%20oil/2013/07/02/compressors-are-heart-of-natural-gas-production
The compression process naturally causes the gas to heat up, so cooling is required before it enters the 

next stage for further compression or before continuing on into the pipeline. This is accomplished 

with large air cooled heat exchangers. Similar in principal to the radiators in cars and trucks, the heat 

exchangers also cool the engine and compressor.

The engine, compressor and heat exchanger are mounted on one or more welded I-beam skids that 

allow the packaged compressor system to be built in a factory and transported to a field site on one or 

more large trucks. The skid also provides a platform for mounting accessory items such as gas 

separators that remove small amounts of liquid from the gas, pulsation bottles that smooth out the 

pressure waves from the compressor, controls, and other equipment. 

Most compressor packages are built in the Southwestern states, however, Youngstown, Ohio 

packager, Dearing Compressor & Pump Co., has enjoyed major growth with the development of the 

Marcellus and now the Utica Shale. Another Ohio company, Ariel Corporation in Mount Vernon, 

manufactures the majority of the large reciprocating gas compressors used throughout the world.

Most large compressor packages are mounted on concrete slabs. Some are housed inside buildings, 

but most gathering compressors operate out in the open. Gas gathering compressors operate around 

the clock, often running more than 8400 hours a year. To put that figure in perspective, driving an 

automobile 15,000 miles a year at an average speed of 50 mph takes only 300 hours. 

A typical new Utica Shale gathering compressor has the capacity to deliver as much as $50,000 of 

natural gas each day, make high reliability extremely important. Computerized controls operate and 

monitor the engine and compressor, keeping the system operating reliably or automatically shutting it 

off if maintenance is required or a problem occurs. Satellite or cellular links allow operators to 

remotely monitor the compressors, and mechanics are automatically called out when unscheduled 

maintenance is needed. With annual maintenance and major overhauls every 4 or 6 years, these large 

compressor packages typically last for more than 20 years. 

10/28/2014

http://www.gasandoilmag.com/gas%20&%20oil/2013/07/02/compressors-are-heart-of-natural-gas-production