Negative carbon dioxide gas power plant integrated with gasification of sewage sludge

Highlights

• The bleed is extracted from the steam-gas turbine.

• The bleed extraction is used as a converting agent for the gasification process.

• The gasification model is integrated to the power plant with CO₂ capture model.

• Pressure of the gasifying agent on the power plant efficiency is examined.

• The bleed extraction as gasifying agent increases the efficiency of the power plant.

Abstract

One of the primary objectives of the negative carbon dioxide gas power plant (nCO₂PP) is to develop an innovative technology confirming the possibility of the use of sewage sludge to produce electricity while having a positive impact on the environment. In this paper, a mathematical model is presented to estimate thermodynamic parameters of the system in relation to the gasification process and changes in such parameters in the bleeds as well as temperature and pressure. The main novelty of this paper is the integration of the gas-steam turbine model with the gasification reactor model in such a way that the effect of the gasification products on the turbine output is established. In turn, parameters from the turbine bleed directly affect the gasification process and cause feedback for the system. Developed code allows determination of parameters such as efficiency of the proposed nCO₂PP cycle, gas composition from the gasifier, temperature in the gas turbine bleed and other related information. The synergy between the CCS plant and the proposed utilization of sewage sludge (which is considered as a renewable energy source) enables the installation to achieve negative overall emissions of CO₂.