PNS Nitrogen Services Pipeline, Maintenance and Cleaning Services

PNS Nitrogen Services (PNS) was founded in 2006 in Emmen, the Netherlands. Emmen is the head office from where the offices in the UK, Germany, France, Italy, Spain, Libya, Croatia, Saudi and China are supported in engineering and operations.

The PNS group consists of PNS Nitrogen Services, PNS Chemical Solutions and PNS Specialty Services. PNS’ core services can be split into those for the process industries, and those for the pipeline industries.

Services for the process industry, refineries and petrochemical plants

• Nitrogen pumping and vaporisation using purpose built, self-contained equipment
• Reactor cooling by nitrogen: accelerated and once through cool-downs
• Plant pre-commissioning including steam and air blowing, hydrostatic and pneumatic testing, oil-flushing, helium leak detection and drying
• Chemical cleaning and chemical supply

Shutdown services including heater/furnace tube cleaning and de-contamination

Pre-commissioning and shutdown operations:

• Hydrostatic testing: various specifications for Gasunie, Fluxys, PD8010, B31.3 and TÜV
• Pneumatic testing: air/nitrogen up to 700barg
• Pipeline cleaning using polyurethane stud pigs, heavy-duty foam brush pigs, bi-directional brush pigs, mechanical scraper pigs, filtration of ethylene/propylene, mobile filter unit and flaring using combustion techniques
• Drying using super dry air, nitrogen and chemicals
• Inhibitor pigging using special pigs and inhibitors
• Pipeline inspections: portable data-logging tools, video inspection, gauging pigs, caliper survey pigs and DCVG surveys
• Rehabilitation: pipeline freezing and 'intra-coat' internal epoxy coating of pipelines

During pipeline cleaning and drying operations, an excessive amount of debris and oxide dust is also removed from the pipe-wall. The dust filter unit is capable of removing all traces of dust from exhausted air at flow rates up to 25,000Nm³/h.

Online pipeline chemical cleaning using reactive chemistry and separators

• Online cleaning to remove black powder
• Wax/paraffin/asphaltene removal
• De-oiling
• De-rusting
• Inhibitor pig runs

Deposits provide an environment to promote under-deposit corrosion leading to catastrophic line failures. Deposits reduce cross sectional area of line, increase roughness and greatly reduce efficiency, resulting in higher cost of compression (which lowers energy efficiency).

Advanced chemicals are very effective at removing ‘black powder’ and paraffin. ‘Black powder’ is recognised by the gas pipeline industry as the leading cause for loss in line efficiency and reduced quality of analysis of in-line-inspection tools.