Auger Gasifier with Vertical Adjustment and Pressurization
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing starved-air gasifiers face challenges in processing non-homogeneous fuels at high throughput while minimizing noxious emissions, leading to high costs associated with pollution control measures.
Innovation Solution
The development of a rotating auger gasifier with a vertically elongated chamber, adjustable auger and bed dam, pressurization, and enhanced air distribution systems, along with steam injection and auxiliary heating, to facilitate continuous and efficient gasification of solid fuels, ensuring controlled combustion and reduced emissions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If starved-air gasifiers are used to process non-homogeneous fuels at high throughput, then fuel processing capacity is improved, but noxious emissions increase
Solution Approach 1:
The gasifier is divided into multiple zones: a combustion zone with intense burning for high temperature and a gasification zone with limited air for syngas production. This spatial segmentation allows different regions to perform different functions, enabling high throughput while controlling emissions through zoned air distribution.
Solution Approach 2:
Different regions of the gasifier are provided with different air supply characteristics. The combustion zone receives sufficient air for complete combustion, while the gasification zone operates with starved air conditions. This local differentiation of air quality enables simultaneous high productivity and emission control.
2Object-generated harmful factors
If scrubbers and antipollution devices are added to control emissions, then emission quality is improved, but system cost increases
Solution Approach 1:
The patent converts the potentially harmful incomplete combustion products into valuable syngas by carefully controlling the gasification zone conditions. The limited oxygen environment transforms what would be pollution into useful fuel gas, eliminating the need for expensive post-combustion cleaning equipment.
Solution Approach 2:
The gasification process itself serves the dual function of fuel conversion and emission control. By designing the reactor to produce syngas through controlled incomplete combustion, the system inherently manages its own emissions without requiring separate antipollution devices, reducing overall system complexity and cost.
3Object-generated harmful factors
If conventional gasifiers are used for complete combustion, then emission control is improved, but fuel throughput and efficiency decrease
Solution Approach 1:
The reactor is segmented into combustion and gasification zones, allowing simultaneous operation of complete combustion (for emission control) and incomplete combustion (for high throughput syngas production). This spatial division enables both objectives to be achieved in different regions of the same system.
Solution Approach 2:
The patent transitions from a single-zone to a multi-zone approach, adding the dimension of spatial differentiation. By operating different zones at different combustion intensities, the system achieves both emission control and high productivity that cannot be obtained in a single homogeneous reactor.
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
This configuration enables reliable, efficient, and cost-effective gasification of various solid fuels, maintaining environmental quality by minimizing emissions and extending equipment life, while allowing for continuous processing and increased fuel throughput.
Implementation Method 1
an auger extending along and conveyed through said chamber, said auger being rotatable about an axis along its length to convey and tumble said solid fuel through said chamber
Implementation Method 2
means for supplying air to said chamber in communication with said fuel bed
Implementation Method 3
U.S. Pat. No. 6,349,658 (describing an auger gasifier with fluidized bed)
Implementation Method 4
gasify solid fuel in a primary chamber (the 'combustor' or 'gasifier' chamber)
Implementation Method 5
Starved-air gasifiers, wherein the air supplied for combustion is controlled in order to control temperature conditions (and the rates of combustion) so as to gasify the fuel as completely as possible
Implementation Method 6
control temperature conditions (and the rates of combustion) so as to gasify the fuel as completely as possible
Implementation Method 7
hot gas recycle mechanism for use with the system
Data Source
AI summary
The auger gasifier described includes, in its preferred embodiments, a vertically elongated (“oblong”) primary gasifier chamber with an auger that can move up and down, allowing for large amounts of fuel input when necessary. This improvement, in turn, requires and/or is facilitated by provision for simultaneous elevation adjustments of the auger and bed dam to assure that fuel material is processed in degrees from the top downward without sweeping massive amounts of the fluidized bed materials towards the output end of the chamber. Another improvement involves provision for pressurization of the primary gasifier chamber, allowing substantial improvements in the speed of processing materials through the gasifier. Due to issues arising from thermal expansion of the refractory material lining the chamber, provision is made for nozzle and refractory imbedded pipe hole thermal expansion capability. Finally, provision is for steam injection into and/or auxiliary heating of the chamber to enhance gasification and the production of syngas.