NCC PFO-PGO Feed Blending for Stable Synthesis Gas Production
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The use of pyrolysis fuel oil (PFO) from a naphtha cracking center (NCC) process as a raw material in the gasification process is hindered by high kinematic viscosity and sulfur content, leading to increased greenhouse gas emissions, high operating costs, and reduced process efficiency.
Innovation Solution
A method involving the use of pyrolysis fuel oil (PFO) and pyrolysis gas oil (PGO) streams from a naphtha cracking center process, processed through specific strippers to adjust kinematic viscosity and flash point, meeting conditions G ≥ 0.5 and F ≤ 0.035, ensuring suitable properties for gasification.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If biomass is gasified using conventional methods, then synthesis gas is produced, but tar components remain in the synthesis gas causing downstream device malfunction
Solution Approach 1:
The patent converts harmful tar components into beneficial synthesis gas components through controlled oxidation. Tar is reacted with oxygen in the gasification zone to produce additional synthesis gas (CO and H2) while eliminating the harmful tar that would otherwise clog downstream equipment. This transforms the tar problem into a useful source of fuel gas.
Solution Approach 2:
The patent changes the chemical and physical parameters within the gasifier by controlling temperature, oxygen partial pressure, and residence time. By maintaining specific temperature ranges and oxygen concentrations in the gasification zone, tar is thermally cracked and oxidized, converting it into synthesis gas components. The parameters are optimized to ensure complete tar conversion while maximizing synthesis gas yield.
2Object-generated harmful factors
If oxygen is blown into the gasifier to reduce tar, then tar content decreases, but fixed carbon is oxidized to CO2 reducing synthesis gas yield
Solution Approach 1:
The patent applies local quality by creating distinct zones within the gasifier with different oxygen concentrations and functions. The gasification zone receives controlled oxygen to convert tar without excessive carbon oxidation, while the combustion zone receives more oxygen for complete carbon oxidation to generate heat. This spatial differentiation allows tar reduction in one zone while protecting synthesis gas production in another zone.
Solution Approach 2:
The gasifier is segmented into functional zones (gasification zone and combustion zone) with different oxygen supply rates and temperature profiles. The gasification zone operates with limited oxygen to favor tar conversion to synthesis gas, while the combustion zone provides the necessary heat through controlled carbon oxidation. This segmentation resolves the contradiction by separating the conflicting requirements of tar removal and synthesis gas production.
3Productivity
If conventional gasification is used, then synthesis gas is produced, but sulfur and nitrogen from biomass contaminate the synthesis gas
Solution Approach 1:
The patent utilizes parameter changes through temperature and oxygen control to alter the chemical behavior of sulfur and nitrogen compounds. By maintaining specific temperature ranges and oxygen partial pressures, the patent promotes the conversion of sulfur and nitrogen into gaseous forms that can be more easily separated or converted into useful products, thereby reducing their contaminating effect on the synthesis gas.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
Reduces greenhouse gas emissions, lowers operating costs, and enhances process efficiency by using PFO and PGO as raw materials, addressing the limitations of conventional refinery residues.
Implementation Method 1
a gasifier for gasifying biomass to convert the biomass into a gas mixture comprising CO, H2, CO2 and other constituents
Implementation Method 2
a thermal cracker for reducing the tar content in the gas mixture produced by the gasifier to a level below 50 ppmv
Implementation Method 3
a sulfur converter for reducing the sulfur content in the gas mixture treated by the thermal cracker to a level below 10 ppmw
Implementation Method 4
a nitrogen remover for reducing the nitrogen content in the gas mixture treated by the sulfur converter to a level below 10 ppmw
Data Source
Figure 1
AI summary
Provided is a method for preparing synthesis gas, and more particularly, a method for preparing synthesis gas including: supplying a cracked gas stream discharged from a cracking furnace of a naphtha cracking center (NCC) process to a gasoline fractionator, separating a side discharge stream from the gasoline fractionator using a first stripper, and separating a lower discharge stream from the gasoline fractionator using a second stripper, wherein a mixed oil stream of a PGO stream and a PFO stream formed by controlling a flow rate of each stream are used.