A leading consulting and contracting company owns and runs a number of ex-situ Thermal Desorption Units (TDUs), which can be operated on both chlorinated and non-chlorinated RCRA, CERCLA, and private industry sites.
With a desorbing capacity of 15 tons/hour of soil at a temperature range of 400°F - 900°F, each single-load TDU is flexible enough to be operated on hydrocarbon and halohydrocarbon sites. The varying environmental standards relating to HCL discharge limits all across the country necessitated the selected pollution control system to remove any HCL released due to the oxidation of chlorinated compounds. Moreover, the control systems needed to be portable as the profitability of this contractor relies on how rapidly the system is assembled, and the site is remediated, and the system is dismantled for shifting to the next site.
Since inexpensive natural gas feeds are not available at many sites, the propane fuel source is required. This requirement would cause unacceptable fuel costs to customers owing to the operational temperature range of 1600°F - 2000°F of a thermal incinerator. After analyzing the capital and operational costs of different solutions, this contractor realized the advantages of a combination of a Chlorinated Catalytic Oxidizer (Chloro-CatTM) and HCL Scrubber. Following a comprehensive technical evaluation and bid process, the contractor selected Global Technologies to provide a mobile treatment package (Figure 1) to address the VOC problem.
Figure 1. Anguil’s Mobile Remediation System for Pollution Control Applications in TDUs.
Global Technologies has vast knowledge in chlorinated catalytic oxidation and HCL treatment, with over 30 such installations for treatment of chlorinated streams from airstripper and Soil Vapor Extraction (SVE) sites. This expertise proved useful in the design and implementation of the appropriate solution. Around 3000 ppmv chlorinated VOC concentration and 5000 SCFM of desorption air at a temperature range of 400°F - 900°F could be exhausted by each rotary kiln TDU.
Dust or dirt plugging problems of the monolithic catalyst cells were eliminated using a high temperature baghouse on the TDU. An induced draft FRP fan was used on the backend of the treatment package by Global Technologies because of the high temperature, highly saturated exhaust from the TDU. Like all Global chlorinated catalytic systems, the 316L stainless steel reactor was equipped with a 316L stainless steel shell and tube heat exchanger.
The chlorinated catalytic system was intended to deliver 99% destruction efficiency at a temperature range of 500°F - 850°F to lower the consumption of auxiliary fuel. It featured safety systems to ensure no system corrosion or HCL condensation. The chlorinated system was placed over a 50' drop deck trailer, which consisted of a Liquid Propane Vaporizer, an HCL Scrubber capable of removing 99.9% HCL in both pure water and caustic mode, and a storage area for equipment transport. The schematic representation of Anguil’s Mobile Remediation System is depicted in Figure 2.
Figure 2. The schematic representation of Anguil’s Mobile Remediation System.
This turnkey package was recently tested for compliance, demonstrating over 99% deterioration of all compounds. As a result, Global Technologies got one more satisfied Global client.
This information has been sourced, reviewed and adapted from materials provided by Anguil Environmental Systems.
For more information on this source, please visit Anguil Environmental Systems.