Fluidized Bed Pyrolysis Apparatus Temperature Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing internally circulating fluidized-bed gasification systems face challenges in achieving high yields of pyrolysis products, particularly oil, due to excessive heating of raw materials, leading to increased carbon dioxide emissions and low product yields.
Innovation Solution
A pyrolysis apparatus with a fluidized-bed furnace divided into a pyrolysis chamber, a main combustion chamber, and a settling combustion chamber, where a first raw material with high carbon content and a second raw material with lower carbon content are supplied simultaneously to the pyrolysis chamber, and the temperature in the settling combustion chamber is controlled to optimize the pyrolysis process.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If the hot fluidized medium from the combustion chamber is used to heat the raw material in the gasification chamber, then the raw material is heated to pyrolysis temperature, but a local hot region is formed causing excessive heating and reduced oil yield
Solution Approach 1:
The combustion chamber is divided into two separate chambers: a main combustion chamber for burning raw material residue and a settling combustion chamber for temperature regulation. This segmentation allows the system to control the temperature of the fluidized medium before it enters the gasification chamber, preventing local hot regions while maintaining adequate pyrolysis temperature.
Solution Approach 2:
The settling combustion chamber acts as an intermediary between the main combustion chamber and the gasification chamber. It receives the hot fluidized medium from the main combustion chamber, regulates its temperature by allowing partial cooling and combustion, and then supplies the moderated heat to the gasification chamber, preventing excessive heating.
2Productivity
If waste plastic with high carbon content is pyrolyzed, then pyrolysis products are generated, but a large amount of carbide is produced that must be burned in the combustion chamber
Solution Approach 1:
The carbide produced from pyrolyzing high carbon content waste plastic is not treated as waste but is utilized as fuel in the main combustion chamber. The carbide burns to generate heat that maintains the temperature of the fluidized medium, which then returns to heat the gasification chamber, creating a beneficial thermal cycle.
Solution Approach 2:
The system merges the pyrolysis process in the gasification chamber with the combustion process in the main combustion chamber through the circulating fluidized medium. The carbide from pyrolysis is combined with the fluidized medium for combustion, and the heat from combustion is combined with the pyrolysis heating requirement, creating an integrated thermal system.
3Speed
If the temperature in the gasification chamber is increased to accelerate pyrolysis, then gas formation increases, but the yield of liquid oil product is reduced
Solution Approach 1:
The system creates different temperature zones in different locations: the gasification chamber maintains a moderate temperature suitable for oil production, while the main combustion chamber operates at high temperature for carbide combustion. The settling combustion chamber acts as a transition zone, allowing the fluidized medium to cool partially before entering the gasification chamber.
4Use of energy by moving object
If biomass or municipal waste with low carbon content is used, then combustion requires large heat input, but most carbon is consumed in the combustion chamber reducing pyrolysis product yield
Solution Approach 1:
The fluidized medium continuously circulates between the combustion chamber and the gasification chamber, transferring heat continuously. This continuous heat transfer ensures that the gasification chamber receives adequate thermal energy for pyrolysis without requiring excessive carbon consumption in the combustion chamber, as the heat is efficiently reused.
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
The controlled supply of raw materials and temperature regulation in the settling combustion chamber enhance the yield of pyrolysis products by preventing excessive heating and maintaining an optimal temperature range for pyrolysis, thereby improving the recovery of intended products such as oil.
Implementation Method 1
a first fluidized bed in the pyrolysis chamber, a second fluidized bed in the main combustion chamber, and a third fluidized bed in the settling combustion chamber
Implementation Method 2
pyrolyzing a raw material in a fluidized-bed furnace... pyrolysis chamber configured to pyrolyze a raw material
Implementation Method 3
a main combustion chamber configured to combust a carbide and a residue of the raw material... a residue of the raw material combusts in the combustion chamber
Data Source
AI summary
The pyrolysis apparatus includes a fluid bed furnace (1), a first partition wall (11) dividing inside of the fluid bed furnace (1) into a pyrolysis chamber (4) and a combustion chamber (5), a second partition wall (12) dividing the combustion chamber (5) into a main combustion chamber (6) and a settling combustion chamber (7), a first gas diffuser (15), a second gas diffuser (25), and a third gas diffuser (35) configured to supply a first fluidizing gas, a second fluidizing gas, and a third fluidizing gas to the pyrolysis chamber (4), the main combustion chamber (6), and the settling combustion chamber (7), respectively, a first raw-material supply device (71) configured to supply a first raw material to the pyrolysis chamber (4) with a first supply amount, a second raw-material supply device (72) configured to supply a second raw material to the pyrolysis chamber (4) with a second supply amount, and an operation controller (200) configured to independently control operations of the first raw-material supply device (71) and the second raw-material supply device (72).