EmissionShield reduces 97% of vented emissions

Reciprocating compressors in the oil and gas industry have three main potential sources of emissions. One is fugitive emissions that arise from leaking seals. Another is indirect emissions from the power generation required to operate the compressor. The third type, known as vented emissions, are caused by the gas that is evacuated whenever the compressor stops. This is where the EmissionShield comes in, the latest product in the HOERBIGER innovation pipeline.

EmissionShield is a static seal system that has been specially developed to seal the piston rod when the compressor is at a standstill. Conventional rod packings are designed exclusively to seal when the compressor is running, and tend to leak considerably when the machine is at a standstill. Although static seal systems are already on the market, they are often characterized by high complexity, low reliability and high costs. EmissionShield, on the other hand, is simple, robust and cost-efficient.

Prototype shows promising measured values
In September 2023, HOERBIGER installed a prototype EmissionShield on a compressor in northern Italy that feeds methane to a gas turbine in a combined-cycle power plant. This plant operates primarily at times of peak load, such as on hot summer days, so it logs few operating hours but many starts and stops. “The power plant has two compressors, so we decided to upgrade just one unit with EmissionShield,” explains Product Manager Guido Pratelli. “We left the other compressor unchanged, and asked the customer to operate the two units alternately.”

As with any prototype test, some unforeseen problems arose. “Nevertheless, we were able to measure an impressive 97 percent reduction in vented emissions from the unit equipped with EmissionShield,” says Pratelli. In terms of the compressor’s total CO₂e footprint, this corresponds to a reduction of 25 percent.

For even a relatively small installation, the annual saving in CO₂e from a single EmissionShield system would be roughly 150 tons – equivalent to the amount of CO₂e that 7,500 trees can absorb in one year during their growth. “Imagine the impact we could achieve if we deployed our technology across the board,” says Pratelli.

_{(l–r) Andreas Kaufmann, Martin Lagler, Jerko Jerolimov (all RnD), Guido Pratelli (PM).}