Safety and Authorization of Biomass Gasification Plants
Cogeneration of electrical power and heat by the way of biomass gasification represents a technology concept to reach the target of an efficiency maximized utilisation of renewable primary sources of energy. Beside the technical availability of biomass gasification plants, the conditions for an authorization proceeding must be reached - due to this the project "Guideline for safety and authorization of biomass gasification plants" was proposed.
For the processing of a knowledge-based technology description a detailed overview of present demonstrated biomass gasification plants with their fundamental process steps (gas generation, gas cleaning and gas utilisation) are given. Based on the technology description and classification it should be possible to assign basic concepts to considered gasification plant concepts. In accordance to the project partners an enumeration of essential points for each process step was given, which showed typical damages in case of non-observation in the past.
For the execution of the authorization procedures relevant national laws, ordinances and norms as well as European guidelines were considered and analysed concerning to relevant paragraphs for the application of biomass gasification plants. The legislator defines a number of requirements for plant manufacturers and operators, which have to be considered in the authorization procedure adequately. Due to the huge variety of legal regulations a "check list for the preparation of technical documentations" for authorization procedures was worked out to give an overview about the required detailed information and technical descriptions. For the respective case a coordination of the procedure with the permitting authorities for the clarification legal question referring to the general law matter and the predefinition of the whole permitting procedure can be recommended.
Depending on the gasification plant concept different material flows have to be handled in an employee-safe and environment-friendly way. In an evaluation biomass gasification plant material flows (liquid, solid or gaseous shape) must be classified belonging to their expected amounts and compositions, to have a basis for the assignment to legal regulations. The guideline provides an overview about these topics with a link to actual regulation of plant emissions in Austria. Due to some unclear regulations in the assignment of plant material flows a clarification was reached - in the topic of flue gas emissions from gas engines in operation with wood gas no limiting value regulation were found, so that the project team worked out a recommendation for limiting values with an additionally description about the difficult conditions in the utilisation of wood gas in gas engines.
Producer gases from biomass gasification plants are multiple component mixtures with strong divergent explosion properties to mixtures with pure burnable components. Due to this an independent work package for the investigation of explosion parameters and explosions hazard study was prepared. The results from the studies of explosion parameters were directly applied in a case study to make suggestions of explosion protective measures. With regard to explosion risks suggestions for a possible strategy in the risk assessment were made, to handle the need of an overall risk assessment. Based on typical product gas compositions, which are referenced by different biomass gasification methods, explosion tests were carried out, to establish a database for the validation of simulation models and calculation of explosion parameters with divergent gas compositions in relation to the tested gas compositions.
In the context of the project processing an essential basis was prepared to overcome barriers for a successful market introduction in this field. It is assumed that the guideline will get a high importance for the plant operators and permitting authorities in the future.
Univ.-Ass. Dipl.-Ing. Friedrich Lettner
Technische Universität Graz
Institut für Wärmetechnik
Tel.: +43 (316) 873-7811
Fax: +43 (316) 873-7305
TU Wien, Institut für Verfahrenstechnik, Umwelttechnik und technische Biowissenschaften,
GE Jenbacher AG,
Amt der steiermärkischen Landesregierung
Amt der oberösterreichischen Landesregierung