Project SynopsisInvestigate, research, and design a new type of quench (particulate knock-out) tower in an existing coke manufacturing facility to significantly reduce emissions and improve operability.
COKE MANUFACTURING FACILITY QUENCH TOWER IMPROVEMENTS
The client, a detail engineering company, was contracted by the ultimate client, a coke manufacturing company, to improve their current quench tower design. The quench tower is a unit operation in the facility where the hot coke is taken to be quenched or cooled down. This creates a plume with particulate matter. The current method to remove the particulate matter is chevron baffles at the top of the tower. The EPA estimates that the baffles are 50% effective. Currently, there is no approved method of measuring emissions from quench towers, but the EPA is working on developing one. The criteria provided was to improve their plume dispersion and thereby air emissions, to find an alternative material for the tower with that would last long term (the current tower is made of wood), and to run pressure drop and velocity calculations for their current tower and the new proposed tower. The ultimate client also wanted their quench basin water quality improved. Process Engineering Associates, LLC (PROCESS) was subcontracted to complete the quench tower part of the project by the client. The tasks involved in this project included:
- Visiting the current site and gathering ideas from operations on improvements.
- Developing and running a Gaussian Plume Dispersion Model for the Quench Tower to determine an appropriate height for the tower and to show ground level concentration improvements between new design and old design.
- Determining theoretical evaporation rates and calculating the amount of air that is pulled into the tower in order to calculate a velocity.
- Determining pressure drop for the tower which includes frictional loss, entrance loss, and loss across the baffles.
- Looking at alternative baffle designs for improved particulate removal.
- Researching EPA regulations and making recommendations on operations to ensure compliance.
- Researching alternative tower shapes (currently the tower is rectangular) and particulate removal systems to aide in decreasing emissions. (No practical alternatives were found as the tower is a natural draft tower and all alternatives exceeded the available pressure drop.)
- Recommending an improved spray system for cleaning the baffles.
- Researching and recommending a better construction material for the bottom 50 ft of the tower.
There was little documented information on quench towers in the public domain. In order to complete this job, the quench tower was related to a stack for design calculations. The baffle system in place is a chevron design and specialized pressure drop equations had to be used. PROCESS had to work closely with the ultimate client’s R&D group on the quench tower parameters and use efficiency and pressure drop equations developed by Calvert for scrubbers and modified by literature methods in order to complete the calculations. A summary of all work, recommendations, and calculations was provided to the ultimate client in order for them to complete the detail design.
- Metallurgical Coke Manufacturing
- Custom process equipment alternatives evaluation
- Custom process equipment design
- Environmental regulation compliance