Air Compressors Info

Compressed Air Energy Storage (CAES) is a way to store energy generated at one time for use at another time. At utility scale, energy generated during periods of low energy demand (off-peak) can be released to meet higher demand (peak load) periods. Compression of air generates a lot of heat. The air is warmer after compression. Decompression requires heat. If no extra heat is added, the air will be much colder after decompression. If the heat generated during compression can be stored and used again during decompression, the efficiency of the storage improves considerably. There are three ways in which a CAES system can deal with the heat. Air storage can be adiabatic , diabatic , or isothermic : Adiabatic storage retains the heat produced by compression and returns it to the air when the air is expanded to generate power. This is a subject of ongoing study, with no utility scale plants as of 2010. Its theoretical efficiency approaches 100% for large and/or rapidly cycled devic...

An air compression is a means by which one type of energy is converted to another. During this conversion certain losses occur because of the rise in temperature of the air as it compressed. In general practice, the air is stored in a receiver and heat is lost both in the receiver and pipe lines running to equipment. Since the rise in temperature of the air is a direct loss of energy. We want to keep it down to a minimum. The ideal method is to compress air isothermally but this is impossible in practice owing to lack of time necessary to affect transfer. Water jackets and inter-cooling can be used to keep the temperature down. These have the effect of reducing the compression index (n) to something less than 1.4. When air is compressed to a pressure to exceeding about 4 bar it is usual to compress it in stages, with intercooling between each stage. This considerably reduces the total amount of work required on the air. For two stages compressing, the air is compressed in the first...

Air is not a perfect gas but for practical purpose the laws relative to perfect gases may be applied to it. Boyle’s law states that: The absolute pressure of a gas varies inversely as the volume, provided the temperature remains constant. p V = a constant where: p = pressure in bar, V = volume in m 3 . Charles’ law states that the volume of a gas under constant pressure, or the pressure of a gas under constant volume, varies as the absolute temperature. Therefore V varies as T, and p varies as T where T is the absolute temperature. If the two laws are combined, we get: p V / T = constant The constant is usually denoted by R and therefore: p V = R T It can be shown that the value of the constant R applicable to air is 287.0 J/(kg K). The relation between the pressure and volume of air during its expansion and compression may be represented by: p V n = R T where ‘n’ has value which depends on the addition or subtraction of heat during the process . When the te...

Approximately 10 % of all electrical power used in industry comes from compressed air. This is proof of its widespread usage but it is also evidence of the potentially large saving in costs which could be achieved if the energy management opportunities are put into practice. Normally, the purpose of compressed air systems in the industrial sectors is to deliver the necessary volume of air at the required pressure and temperature to the correct places. Compressed air is used for operating pneumatic equipments, cleaning purposes, and other general services. This is accomplished by a distribution system consisting of pipes, valves and fittings. The Compressed Air pipe work is arranged in the form of ring mains with interconnections to points of end-users. Careful evaluation of existing compressed air systems can ensure against improper operation, and poor energy utilization. Alert design, operations, and maintenance personnel, with an awareness of energy management, can achieve signif...

Let's continue from [ Compressed Air System Energy-Reduction Case Study (Part 1) ] Compressed Air Energy-Reduction Strategy Project Goals and Implementation Following the IAC assessment, FUJIFILM’s maintenance team formulated project goals and an implementation plan that centered on the utilization of existing facility infrastructure and equipment. The team’s implementation strategy was divided into three phases and focused on increasing the system’s storage capacity to handle production peaks and valleys; lowering air compressor operating pressure; repairing system leaks; and ultimately, operating the facility with one compressor. The team’s strategy was also aided by the company’s closure of its Orange Park, Florida, operations. This facility housed a 75 horsepower (HP) air compressor, a dryer, and a receiver, which the Dayton facility incorporated into its efforts. Project success, then, depended on the accomplishment of four specific goals: To increase system redundanc...

FUJIFILM Hunt Chemicals U.S.A. Achieves Compressed Air System Energy-Reduction Goals with a Three-Phased Strategy. In an attempt to eliminate equipment failures and downtime issues associated with the plant’s compressed air system, FUJIFILM Hunt Chemicals U.S.A.’s in-house maintenance team worked with a team of faculty and students from the Tennessee Technology University Industrial Assessment Center (IAC) to conduct an assessment at its Dayton, Tennessee, facility to identify opportunities for improvement. Following the assessment, the team formulated an implementation plan that would increase the system’s reliability, reduce system maintenance costs, reduce the facility’s overall energy use, and eliminate the use of nitrogen when compressed air systems are down. The Energy Situation The Dayton facility was experiencing excessive downtime due to chronic air compressor failures and significant inefficiencies throughout its compressed air system. In 2007 alone, system operating costs...

Stabilizing system pressure is an important way to lower energy costs and maintain reliable production and product quality. The need to stabilize system pressure should be guided by the compressed air demand patterns and the minimum acceptable pressure level required for reliable production. High-volume intermittent air demand events can cause air pressure to fluctuate, which is often misinterpreted as insufficient pressure. In some cases, improperly set compressor controls will cause another compressor to start, but because of the time required for the new compressor to ramp up, there will be a shortfall of air supply to the system. Such a delay can cause the system pressure to decay, resulting in lost production. Three methods can be used to stabilize system pressure: adequate primary and secondary storage, Pressure/Flow Controllers (P/FCs), and dedicated compressors. Primary and Secondary Storage One or more compressed air applications having large, intermittent air demands can...