Problems of sewage sludge energy utilization in a fluidized bed boiler E-75-3,9-440 DFT

RELEVANCE of the study means the recommendations development for the efficient energy utilization of sewage sludge in the fluidized bed boilers. THE PURPOSE. To consider problems of energy utilization of sewage sludge. Conduct an energy audit of the fluidized bed boiler E-75-3,9-440 DFT during the combustion of sewage sludge together with wood waste from pulp and paper industry. Conducting a proximate analysis of sewage sludge and wood waste. Conducting an elemental analysis of the fluidized bed material. METHODS. Samples of sewage sludge and wood waste were taken from the fuel supply line of boiler E-75-3,9-440 DFT. Retzsch RM 200 ball drum mill and a Retzsch AS 200 Control sieve analyzer were used to prepare samples. Ultimate analysis of sewage sludge was performed by X-ray fluorescence spectroscopy on an EDX-8000 spectrometer. This method identifies metals and elements of the sample by detecting their energy signatures. Hydrogen, nitrogen and carbon content was determined using the EuroVector EA-3000 analyzer. Calorific value of the studied samples was determined using an IKA C 2000 Basic Version 2 calorimeter with a LOIP FT-216-25 liquid cryothermostat. Energy audits were carried out under the established thermal regime of the boiler. RESULTS. Research results have shown that during the combustion of sewage sludge in a fluidized bed boiler E-75-3,9-440 DFT operating conditions are very different from the calculated ones, which is associated with the problems of slag formation, erosion due to the high ash content of the sludge, as well as problems associated with the operation of the fluidized bed due to the high humidity of the fuel. CONCLUSION. Recommendations are given on improving the energy efficiency of wastewater sludge combustion in a fluidized bed boiler E-75-3,9-440 DFT.

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