Case Study (36 KB PDF)

Summary

The study considered different variants of conjunctive combustion of waste defibred paper sediments with wood waste, produced in the region of the Northwest Slovakia. The priority task of the realizers was to ensure effective energy utilization of waste sediments, which are increasing from year to year.

The study was developed by REMA in cooperation with Biomasa Association, Zilinska Teplarenska Inc. (local heating plant in Zilina), Tento Inc. (local paper mill in Zilina), boiler manufacturers and representatives of important regional institutions. The executor of the study was Energy Research Institute in Bratislava. The costs for the study elaboration reached 14 000 EUR. The industrial plants (Stredoslovenska energetika Inc. and TENTO Inc.) together with REMA Zilina raised the financial resources.

Considering the economic criteria, which were a priority for the further construction, the executor did not recommend to realize the building in the existing economical, environmental and legislative conditions.

Results

The result of the Study offered records and details for the final decision about construction of a new boiler for combustion of paper sediments.

Considering the economical effectiveness, the most convenient variants were chosen: variant I. (co-firing sediments with coal or wood biomass) and variant III. (co-firing sediments in the form of briquettes with waste wood biomass and coal) conditioned to. Payments of TENTO Inc for this service at 1000, - Sk/t, which is five times more expensive in comparison to the present fee for the sediments liquidation. Concerning the technical and operational criteria, the most feasible was again variant I., in view of the environmental criteria, the most acceptable was variant III (co-firing paper sediments with waste wood biomass met the best the original objectives of the project - reducing production of emissions, ensuring energy effectiveness and elimination of local and global emissions. Unfortunately, the investment costs for implementation of both variants extremely high.

With emphasis to the economic criteria, which were priority for the investor's decision, the Study did not recommend to solve the liquidation of sediments through constructing a new boiler for the sediments combustion in the Heating plant (Annex.2). Providing the legislative, economic and environmental changes towards the restriction of the present process of the sediments utilization, the Study recommended to apply fluid technology of combustion.