Numerical and Statistical Analyzing of the Effect of Operating Parameters on Syngas Yield Fluctuation in Entrained Flow Coal Gasification Using Split-Plot Design

Abstract

For a coal-based production system with entrained flow coal gasification, the fluctuations in syngas yield (SY) affect the stability of downstream sections directly. The focus of this study is to analyze how some important operating parameters affect these fluctuations in SY for a typical entrained flow coal gasification, Shell coal gasification process (SCGP). In this study, we carried out a set of numerical simulation experiments in Aspen Plus simulator for a demonstration SCGP gasifier. These experiments were arranged using a special design of experiment (DoE) method, split-plot design. Then we systematically analyzed the effects of pressure (P), oxygen to coal ratio (O/C), and steam to coal ratio (S/C) on the Range and standard deviation (StDev) of SY using some statistical techniques. The results show that split-plot design is an appropriate DoE method to investigate and analyze the effects of the operating parameters on the fluctuations in SY. For the demonstration SCGP process, the fluctuations in SY are mainly affected by P and O/C. Among them, P is the dominant factor and O/C is an important factor, while S/C influences the fluctuations in SY slightly. The lowest Range and StDev of SY could be obtained only when P is at a higher level and O/C as well as S/C is at a lower level. This is the ideal condition for realizing a moderate robust syngas production.

Modeling Study of the Slag Behaviors Based on Temperature–Time–Viscosity of Crystalline Slag in an Entrained-Flow Gasifier

“…There were many researches about the slag behaviors inside the gasifier, − but the in situ experiment study for slag behaviors in the gasifier was limited due to the high-temperature and -pressure environment. Wang et al conducted a cold model experiment which used the syrup to simulate the liquid slag at the slag tapping hole.…”

Modeling Study of the Slag Behaviors and SiC Refractory Wall Corrosion on the Top Cone of a Membrane Wall Entrained-Flow Gasifier

“…The entrained-flow gasification is one of the most widely used technologies in the field of energy conversion because of its cleanliness and high efficiency . Security and stability are the primary consideration when designing and operating a gasifier . According to the position of the burner, slag tap, and syngas outlet, an entrained-flow gasifier can be divided into several types, such as a Shell gasifier, a GE gasifier, and an OMB gasifier, as shown in Figure .…”

“…1 Security and stability are the primary consideration when designing and operating a gasifier. 2 According to the position of the burner, slag tap, and syngas outlet, an entrained-flow gasifier can be divided into several types, such as a Shell gasifier, a GE gasifier, and an OMB gasifier, as shown in Figure 1. In general, the top of a gasifier will be conical or dome, which helps to collect the syngas (such as in Figure 1a), reduce the backflow area (such as in Figure 1b), or increase the structure strength (such as in Figure 1c).…”

Markov Chain Simulation of Coal Ash Melting Point and Stochastic Optimization of Operation Temperature for Entrained Flow Coal Gasification

“…Among the clean coal technologies, coal gasification is regard as a promising utilization of coal because of its low technology cost and high conversion rate [5]. In the coal gasification practice, the basic equipment can be grouped into three main categories: fixed bed gasifiers, fluidized bed gasifiers and entrained flow gasifiers [6,7]. Differ from fixed bed and fluidized bed gasification, entrained flow gasification 2 of 23 operates at a higher temperature (above the melting temperature of ash) with smaller particles and produces high quality syngas with low methane and free tar content.…”