By Pragnesh Desai
More so than ever before, companies are looking for reliable equipment solutions to maximize production and minimize downtime. In particular, temporary air and nitrogen solutions play a valuable role in maintaining seamless operations during several phases in industrial projects. Specialized rental solutions like portable 100% oil-free compressors, onsite nitrogen generators and accessories are usually required by plant owners, EPC* contractors and general utility contractors for breakdowns, facility upgrade projects, new builds and during turnarounds or maintenance of plants.
For short or long-term demands, planned contingencies or unexpected emergencies, specialist rental companies provide a range of options for cost and energy efficient compressed air and nitrogen solutions. At these companies, a team of qualified engineers are equipped to design the most suitable installation, with close attention paid to quality of service, environmental care and safety.
Specialized rental solutions: product range
Air compressors can be categorized as either oil-free or oil flooded. The type of compressor selected for the application is critical as the air quality between the different categories varies substantially. The TÜV** in Germany classifies Class 0 oil-free air compressors as having no detectable traces of oil in the compressor outlet, and Class 0 is mandatory where even the smallest amount of oil cannot be tolerated. Oil flooded compressors may be acceptable only when oil ‘carry over’ to the application can happen. Single, two or three stage compressors are available to provide low, medium and high pressure Class 0 or oil flooded air.
Low emission diesel engines and electric-driven oil-free compressors are the types most commonly utilized in the industry.
For moisture-free air, desiccant air dryers can be supplied together with compressors to achieve different dew points. The typical dew point requirement is -40°F (-40°C). However, solutions for extra dry air with dew points of -94°F (-70°C) are also available.
Onsite nitrogen generation using membrane technology to supply nitrogen gas at different flow and pressures, with purities up to 99%, is becoming a preferred choice for most customers. A typical nitrogen spread includes Class 0 feed air compressors and nitrogen membranes. Most of the nitrogen applications in existing plants require nitrogen pressure up to 150 psi(g) / 10 bar(g). For higher pressure nitrogen applications during pre-commissioning and commissioning, high-pressure air compressor and boosters in excess of 150 bar(g) / 10 bar(g) are also available. The onsite nitrogen membrane generation system provides nitrogen on demand and at various purities, flows and pressures. It also eliminates the boil-off losses during the transportation and gasification of liquid nitrogen, which can sometimes be substantial.
The key factors to be considered for the selection of temporary equipment suppliers are as follows:
- Does the supplier have a thorough understanding of industry processes and needs?
- Does the supplier have an excellent safety record?
- Does the supplier work with high quality and reliable equipment?
- Does the supplier offer a total solution capability?
- Does the supplier offer continuous service support?
- Can the supplier provide past project references?
Providing the total solution
When considering the procurement of a specialized rental solution for a temporary need, it is important to look at the total solution, not just the equipment supply. It is advantageous to have contingency planning of temporary air and nitrogen requirements for the critical process and applications system and to work with a supplier that is well educated of the various applications and who has excellent project management and engineering capabilities. A supplier qualified in these attributes can add significant value during the contingency planning process.
The logistics of the operation can often be managed from project commencement, to completion and installation. Commissioning and operator services may also be useful where site labor is constrained. Energy management, such as re-fuelling services, also reduces the project management workload.
Final consideration should be given to the level of remote monitoring required. This is where a satellite-based system can alert the supplier of any potential problems. A rental company that provides this service, will remotely monitor fleet performance to improve machine up-time, security and safety.
The reliability and quality of equipment, the ability to provide the highest quality oil-free air, specialized knowledge and engineering capabilities make a compressed air and nitrogen rental company a preferred choice for industrial customers worldwide.
*EPS stands for Engineering, Procurement and Construction.
** TÜV is short in German for Technischer Überwachungsverein; in English Technical Inspection Association.