Disintegration of sewage sludge

Disintegration of sewage sludge

SPANGLER – the Plus of conservation of resources.

Pondus® Verfahrenstechnik GmbH has commissioned Spangler Automation to install a new disintegration plant in the sewage treatment plant Erlangen. This is a process for the digestion of microorganisms in sewage sludge, the so-called thermal-chemical cell disintegration. Due to a preliminary project, many parallels could be drawn, and the project could therefore be implemented relatively quickly.

Thermal-chemical cell disintegration

With the process of thermal-chemical cell disintegration (hydrolysis) sewage sludge is heated up in a special reactor and with the addition of base, the cell membrane is broken down to the greatest possible extent. In this way, the organic residual material in the digested sludge is reduced and dewatering is improved. The dry proportion of the dewatered sludge is increased and the amount of sewage sludge that must be disposed is reduced. The residual heat included in the sludge after heating is re-used in the following process steps such as digestion.

Versatile automation and control technology

Spangler Automation has planned, produced and programmed the automation technology for this system. Three control panels were equipped with the central Siemens PLC S7-1516. In addition, the plant was connected to the control system that can be operated locally. With the Siemens IPC477E 22 inch a clear layout was created and enables intuitive working at the plant. The coupling of the three control panel fields was implemented with the decentral interface module ET200SP. The multifunctional Siemens measuring instrument PAC3220 is used for the energy analysis; power and voltage values are online available. The continuous and equal feed of the plant technology is guaranteed by pumps, controlled by two frequency conformers.

Basic scheme for thermal-chemical cell disintegration, Source: Pondus®
Installation and assembly of the reactor







Thermal-chemical cell disintegration in Erlangen