Needle Coke Pressure Stabilization Tower
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The industrial production of needle coke is challenging due to its temperature- and pressure-changing characteristics, leading to unstable device operation and poor separation effects in the coking fractionation unit.
Innovation Solution
A system and method for producing needle coke that includes a coke tower, a pressure stabilization tower, a buffer tank, and a coking fractionation tower, where the pressure at the top of the coke tower is controlled through the pressure controller at the top of the pressure stabilization tower, reducing the fluctuation in oil gas discharge and improving pressure control stability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If temperature- and pressure-changing operation is adopted for needle coke production, then needle coke can be formed through liquid crystal intermediate phase, but the device operation becomes unstable and pressure control becomes difficult
Solution Approach 1:
The system divides the coking process into distinct stages (liquid crystal formation stage at 390-460°C and needle coke formation stage at 450-510°C) with different temperature and pressure conditions. The pressure control is segmented between the coke tower and pressure stabilization tower, allowing independent optimization of each stage's parameters.
Solution Approach 2:
The system dynamically adjusts temperature and pressure parameters during the coking process. The temperature is gradually raised from 390-460°C to 450-510°C, and pressure is adjusted from 1.5 MPa to 0.5 MPa then held constant. The pressure controller continuously monitors and adjusts the pressure at the top of the pressure stabilization tower to maintain stable operation.
2Manufacturing precision
If temperature is raised during the reaction process, then needle coke formation is promoted, but violent thermal cracking and thermal polycondensation reactions occur causing large amount of oil gas discharge
Solution Approach 1:
The coking process is conducted in periodic stages: first stage at 390-460°C for liquid crystal formation with mild reaction and lower oil gas production, then temperature is raised to 450-510°C for needle coke formation. This periodic temperature adjustment allows controlled progression through reaction intensities.
Solution Approach 2:
The pressure stabilization tower acts as an intermediary between the coke tower and fractionation system. It receives oil gas from the coke tower, stabilizes the pressure, and then feeds to the fractionation system, reducing the direct impact of temperature-induced oil gas fluctuations on the fractionation unit.
3Reliability
If pressure control system adjusts pressure at the top of the coke tower, then pressure can be maintained, but the adjustment range is wide and the system cannot be always maintained in proper operation range
Solution Approach 1:
The pressure stabilization tower serves as a mediator that receives oil gas from the coke tower and provides pressure stabilization. The pressure controller at the top of the pressure stabilization tower adjusts pressure within a narrower, more stable range compared to direct control at the coke tower top, improving control precision and operational stability.
Solution Approach 2:
The pressure stabilization tower provides a buffer zone that cushions pressure fluctuations before they reach the fractionation system. This prior cushioning allows the pressure controller to maintain pressure within a proper operation range more effectively by absorbing sudden pressure changes.
4Productivity
If the amount of oil gas discharged fluctuates greatly, then the fractionation unit throughput fluctuates greatly, but the separation effect becomes poor and operation stability is affected
Solution Approach 1:
The pressure stabilization tower acts as an intermediary that decouples the fractionation unit from direct exposure to oil gas discharge fluctuations from the coke tower. By stabilizing pressure and controlling the flow of oil gas to the fractionation system, it maintains more consistent throughput and improves separation effectiveness.
Solution Approach 2:
The pressure stabilization tower provides beforehand cushioning by absorbing and dampening pressure and flow fluctuations before they reach the fractionation unit. This cushioning effect maintains more stable operating conditions in the fractionation system, improving separation precision and operational stability.
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 proposed system achieves improved stability in the needle coke production process by reducing fluctuations in the coking fractionation unit's throughput and enhancing separation precision, while also simplifying pressure control and reducing the risk of coking in the pressure stabilization tower.
Implementation Method 1
a pressure controller is provided at the top of the pressure stabilization tower for adjusting the pressure at the top thereof; the pressure at the top of the coke tower is controlled through the pressure controller at the top of the pressure stabilization tower
Implementation Method 2
the oil gas from the coke tower is received and separated into an overhead light fraction and a bottom oil
Implementation Method 3
the oil gas from the coke tower is received and separated into an overhead light fraction and a bottom oil
Implementation Method 4
a buffer tank provided with an inlet, a first bottom oil outlet, and a second bottom oil outlet, for receiving the bottom oil from the pressure stabilization tower and providing a buffering action
Implementation Method 5
a coking fractionation tower provided with an inlet, a light oil outlet and a heavy oil outlet, where the bottom oil from the buffer tank is received and separated into a light oil and a heavy oil
Implementation Method 6
the temperature in the coke tower is 390-460 °C, and intermediate phase liquid crystal is formed in the system; in a second reaction stage, the temperature in the coke tower is raised to 450-480 °C, and the intermediate phase liquid crystal begins to solidify
Data Source
Figure 1~2
Figure 3~4
Figure 5~6
AI summary
Disclosed are a system for producing needle coke and a method for producing needle coke using the system, the system comprising: a coke tower, a pressure stabilization tower, a buffer tank and a coking fractionation tower, wherein a pressure controller is provided at the top of the pressure stabilization tower for adjusting the pressure at the top thereof, an oil gas outlet of the coke tower is in communication with an oil gas inlet of the pressure stabilization tower through a pipeline, and no pressure controller for adjusting the pressure at the top of the coke tower is provided in the coke tower or on the oil gas pipeline connecting the coke tower to the pressure stabilization tower. The system and method can improve the operation stability of the needle coke production process, and in the whole reaction period, the fluctuation of the throughput of the coking fractionation unit is small, the separation precision is high, the pressure of the coke tower is easy to control, and the operation stability of the whole system is greatly improved.