CAHS — compressed air generation without electricity

Reduce compressed air costs and increase energy efficiency

Compressed air is used in many sectors and in many different ways in the modern industry. It has become indispensable. Industrial plants often use compressed air for pneumatic drive and transport, for example of bulk materials or liquids. An important advantage of pneumatic systems over purely mechanical systems is above all the possibility of extremely high operating speeds.

The problem: compressed air is expensive

Compressed air generation is very expensive. On average, about 10 percent of a company’s total energy costs are spent on generating compressed air. In certain industries, up to 30 percent is spent (e.g. automotive).

The generation of compressed air thus represents an enormously high cost factor in most companies. Rising electricity prices are making conventional compressors and outdated distribution systems increasingly uneconomical. Further energy costs arise from the need for heating and process heat, for example to heat production halls or to heat products for production or drying.

Potential savings can be made by using the waste heat that is generated during the production of compressed air. Some of this can be recovered and fed into the system as process heat.

The solution: Compressed air as a by-product of heat generation with gas (CHP principle).

We go a step further with our compressed air heating system (CAHS), where compressed air is produced as a by-product of heat generation.

The CAHS uses a gas-fired combustion engine to generate sensible exhaust gas heat that can be used industrially. A screw compressor is driven at the same time via a clutch – the compressed air generated (up to 13 bar depending on the pressure level) falls off as a by-product of heat generation. 

The available heat from the engine cooling water, the exhaust gas and the compressor oil is fed to the heating circuit via a heat exchanger for heat recovery, whereby a constant temperature can be maintained in the heating flow. The gas-fired provision of compressed air in this way generates up to 100% useful heat.

In summary: Heat and compressed air are provided locally according to the principle of a combined heat and power plant via a combustible medium (natural gas, biogas); no electricity is required to operate the compressor. This means that the conventional operating costs for compressed air generation are completely eliminated. The compressed air is produced as a pure by-product of the industrial heat generated.

Individual adaptation options of the compressed air heating system

The CAHS is available in various sizes with pressure ratings of 8.5 bar /10 bar /13 bar. The modular design of the entire system also provides the highest possible degree of flexibility.

1. The waste heat of the CAHS can be used directly or indirectly, for example:

  • Compressed air treatment with heat-regenerating adsorption dryer
  • Provision of “technically oil-free” compressed air by catalytic converter technology
  • Granulate drying in the plastics industry
  • Coupling to various heat transfer media, e.g. thermal oils

2. The equipment of the CAHS can be optionally adapted to the needs of the application:

  • Sound proofing hood
  • Design of the required heat exchangers
  • Compressed air preparation
Due to the heavy burden on the electricity price with charges and levies, the CAHS quickly pays for itself in industrial use compared to conventional compressed air generation. In addition to the economic advantages, the system also has an ecological advantage over the separate generation of compressed air and heat. The use of the CAHS’s 08/630 for a running time of 8,000 hours leads to an annual saving of 315 tonnes of CO2 compared to separate provision.