PETpla.net Insider 01+02 / 2018

TRADE SHOW REVIEW PET planet Insider Vol. 19 No. 01+02/18 www.petpla.net 38 Energy and cost savings in PET compressor installations Ways and means of saving energy Sufficient and reliable compressed air supply is one of the main requirements for running a modern blow moulding operation. Liftetime costs for high-pressure, oil-free, mul- tiple-stage piston compressors are dominated by energy, which accounts for 80% of the total, dwarfing the outlay for capital investment and maintenance (based on a 10-year life cycle). AF Compressors claims that its latest range of oil-free PET compressors improve efficiency and generates costs savings through improved control, regulation and heat recovery. Energy savings through regulation of motors and air flow SIS: Smart Inverter Starter Induction motors, as used in com- pressors, have a very high starting current; often many times the nominal current. This can cause problems with plant power networks if, for example, several motors in the factory start at the same time. Using standard electric motors, AF Compressors addresses this problem with its SIS (Smart Inverter Starter). Developed by Ateliers François Liège, this inverter system for starting purpose only, ensures that the starting current never exceeds the nominal current and that the full load power never exceeds 100%. There is no need for additional shielded cables, line filters or other protection devices. This innovation on the market comes along with the adjustment of air flow, the AFS System. Adjustment of air flow Another way to save energy is to adjust the air flow in cases where less than full air capacity is needed. AF’s Adjustable Air Flow System (AFS) does this by deployment special work- ing protocol around the acting com- pressor cylinder. Normally, when full air capacity is required, a 1 st stage double acting cylinder raises atmospheric air from 1 to 4 to 5 bar. At full load, the 1 st stage double action cylinder produces 100% of rated capacity and provides of required 100% air to the blow mould- ing machine. When full air capacity is not required: the 1 st stage cylinder compresses atmospheric air only on the upward stroke of the piston. Shown: 50% on the very top and 75% below. In circumstances when full air capacity is not required, the system around the acting cylinder works in a different way: the 1 st stage double acting cylinder compresses air upward only. The system automatically unloads the lower part of the cylinder and delivers the air flow required in the system. AFS is available on new units and can also be retrofitted. Frequency Inverter Alternatively, depending on the specific PET bottling production profile, a classical frequency inverter can also be a good choice to increase efficiency and decrease power consumption. AF Compressors also offers conven- tional Variable Frequency Drives which are based on Siemens Sinamics. A pre-lubrication oil pump, a specific motor and other special device such as shielded cabling are included in the package offered by the company. Heat recovery system Energy savings through heat recovery Efficient heat recovery can also achieve significant cost savings. AF offers two basic systems: one for higher water temperatures – around 90°C – and the other for tempera- tures around 40-45°C. The heart of the “Heat Recovery System 90°C” is a special double cooler, for the 2 nd and 3 rd stage. In this system, the compres- sor can run with a smaller water pump equipped with a frequency inverter