Technology Overview

Technology Type:
Off-Gas Treatment

Trade Name and/or Model Number assigned by vendor:
VOC Control and Recovery

Technology Scale: Indicates the operational status of the technology.
Full Scale - Available equipment is sized and commercially available for actual site remediation.

Vendor Services:
Equipment manufacturer
Subcontractor for characterization, monitoring, or measurement

Patent Information
Registered trademark
Vendor has exclusive license
Technology patented
Patent Pending

Verification Program Information
This technology is in the Superfund Innovative Technology Evaluation (SITE) Program.
This technology is being tested, or has been tested, in EPA SITE Emerging Technology Program.
This technology is being tested, or has been tested, in EPA SITE Demonstration Program.

Description of Technology:
Describes the treatment process device or technology, including scientific principles on which the technology is based; key treatment steps; unique and inovative features; whether full-scale system is/will be batch, continuous, or semicontinuous; and whether the technology is above ground or in situ.
NUCON International, Inc. has developed and commercialized an innovative off gas treatment system using a propriatary combination of hot nitrogen stripping of adsorbent beds and a reverse Brayton Cycle turbo expansion system to cool and condense the recovered liquid contaminants.

The raw off-gas is processed through carbon beds to remove and concentrate the extracted solvents. These solvents are then stripped and condensed to liquid to minimize the volume of waste disposed.

Nitrogen regeneration of carbon adsorption concentration beds eliminates problems of increased volume of the recovered contaminants compared to steam regeneration. This unique process also eliminates the creation of secondary wastewater.

The registered trade name of this system is "BRAYSORB".

Technology Highlights:
Describes the key marketable features of the technology in terms of contaminants treated, performance, implementation, or cost. Includes the key marketable features of the technology, such as treatment niche and advantages over other technologies.
The NUCON BRAYSORB Solvent Recovery System (SRS) is a new application of well understood and proven technologies. The engineering and components that make up a BRAYSORB SRS are all highly reliable and do not require operation outside industrially accepted practice. The combination and application is the novel innovation that provides significant advantages. With only two active components that are simple rotating machines (a blower and turbo expander/compressor) long term reliability is exceptional.

Energy efficiency is very high based on the use of efficient components and engineered recovery. Over 60 percent of the energy given up by the process gas flow when cooled by passing through the turbo expander is recovered in the turbo compressor. The gas out of the expander is used to precool the inlet gas after the solvents have been passively phase separated.

No water is added to the recovered solvents and no secondary waste is created.

Technology Limitations:
Describes the technical limitations such as specific contaminants or contaminant combinations, temperature, moisture content, or chemical properties of the contaminant, that could adversely affect applicability or performance.
The BRAYSORB SRS is efficient only for solvents that are reasonably well adsorbed on activated carbon and that can be stripped at temperatures lower than about 350.5 degrees Fahrenheit.

The lower the boiling point of the recovered solvents the more advantageous the BRAYSORB SRS is compared to standard mechanical refrigeration systems.

Other Comments:
Provides additional technology information, such as technology history, status, capabilities, experience, and applicable permits obtained (e.g., TSCA, RCRA). Also describes plans for future development of the technology, including diversification of media and/or contaminants treated.
The NUCON BRAYSORB SRS has been successfully demonstrated for soil remediation off-gas treatment at the DOE Savannah River site. This was done with a trailer mounted mobile system that has demonstrated the process at a variety of sites and applications in the U. S. and Canada.

Large flow permanently installed BRAYSORB SRS have been in highly efficient operation at production factilities for over five years.

There are currently two mobile systems and seven large scale fixed systems in successful operation.

Media:
Actual - have been treated by this technology.
Potential - may be applied in the future.
Actual Potential  
Off-gas generated from a primary innovative treatment technology


Contaminant Groups treated:
Actual - have been treated by this technology.
Potential - may be applied in the future. If this technology is materials handling/physical separation, delivery/extraction, or is an equipment vendor, this question may not apply.
Actual Potential
Halogenated volatiles
Nonhalogenated volatiles
Solvents


Waste source or site types of sites treated:
Actual - have been treated by this technology.
Potential - may be applied in the future.
Actual Potential
Chlor-alkali Manufacturing
Dry Cleaners
Gasoline Service Station/Petroleum Storage Facility
Herbicide Manufacturing/Use
Machine Shops
Municipal Landfills
Paint/Ink Formulation/Use
Pesticide Manufacturing/Use/Storage
Petroleum Refining and Reuse
Other Organic Chemical Manufacturing/Use
Other Inorganic Chemical Manufacturing/Use
Semiconductor Manufacturing
Wood Preserving


Full Scale Equipment/Capabilities:

Full-Scale Facility is: Transportable Fixed In situ
Number of Full-Scale Systems:
Number planned/in design: 1 Projected completion (MM/DD/YY): Not Provided

Capacity Range:
100 to 10000 scfm (units)

Number of full-scale cleanups conducted by using this technology. Only applications of this technology that were applied at petroleum/hazardous waste sites are considered.
vendor initiated or completed - as a subcontractor or prime contractor: 0
equipment manufacturer - other firms using this technology: 0

Full Scale - Major Unit Process:
MAJOR UNIT PROCESSES

PREPROCESSING

-- VOC laden off-gas is generated by some process upstream of the NUCON system.

-- Particulate filtration is performed if required.

PROCESSING

-- VOC laden off-gas is passed through carbon adsorbent beds which remove the VOCs and clean air is discharged to the atmosphere.

-- When a carbon adsorption bed has reached its VOC capacity it is taken off-line and regenerated.

-- The first step in regeneration is to purge the oxygen from the carbon adsorption bed and system with nitrogen.

-- When the oxygen has been reduced to an acceptable level a closed loop flow of hot nitrogen strips the VOCs from the adsorbent.

-- The VOCs in the nitrogen are condensed by cooling through a turbo expander and gas to gas heat exchanger for energy efficiency.

-- A major part of the energy given up by the gas in turbo expansion is recovered by the compressor side of the turbo unit. The gas to gas heat exchanger also conserves system energy.

-- The VOC free nitrogen is heated by the turbo compressor and then the motor driven compressor which is the prime mover of the system.

-- The hot clean nitrogen then returns to strip the adsorbent beds until they have been regenerated.

POST PROCESSING

-- Recovered VOCs are disposed of as water-free liquids.

Price Factors:
Estimated Price Range.
A "ballpark" estimate per unit of waste treated. Includes waste preprocessing and excludes excavation, permitting, and disposal of residues.
$ to $ per (units)

Factors Affecting Unit Price.
Following is a ranking of items that will have a significant effect on the unit price. If the technology is in situ, excavation and waste handling did not affect price. (1 = highest)
Rank Factor  
1 Initial concentration of contaminant
1 Target concentration of contaminant
2 Quantity of waste
3 Labor rates
3 Utility/fuel rates
4 Site preparation

Full-Scale Cleanups
Number of full-scale cleanups using this technology which has been initiated or completed. 0
Number of full-scale cleanups by other firms using this technology. 0

Pilot Scale Equipment/Capabilities:
Pilot-Scale Facility is: Transportable Fixed In situ
Number of Pilot-Scale Systems
Number planned/in design 1 Projected completion (MM/DD/YY)
Number constructed 1

Number of times this technology has been used at the vendor facility or at other locations to conduct pilot-scale studies on actual wastes. Multiple studies pertaining to the same site has been counted only once, regardless of the number of different wastes or tests. Tests on surrogate wastes are not included.
15

Pilot-scale treatability studies on some types of waste can be conducted :
At vendor location At a contaminated site

Prorated capacity of batch processes.
50 to 250 scfm (units) Not Applicable

Quantity of Waste Needed for Pilot-Scale Treatability Study. Estimated range of quantity of waste needed to test, at the pilot scale, the feasibility of this technology on a specific waste.
50 to 250 scfm (units)


Pilot Scale - Major Unit Process:
The mobile pilot plant is a complete BRAYSORB SRS and operates the same as a full-size system described in the full-scale section.

Bench Scale Equipment/Capabilities:

Bench-scale treatability studies can be conducted on some types of waste at the vendor location.

Estimated total number of bench-scale studies conducted on actual waste from different sources or sites. Multiple studies pertaining to the same site counted only once, regardless of the number of different wastes or tests. Did not count tests on surrogate wastes. 20


Bench Scale - Major Unit Process:
Two bench scale systems are in use at NUCON. One glassware 2 cfm and one stainless 10 cfm. These duplicate the full-scale BRAYSORB and BRAYCYCLE Solvent Recovery Systems so all relevant parameters can be determined on a bench scale.

Literature and Technical References:
Author(s):
NUCON International, Inc.
Title:
BRAYCYCLE A Process By NUCON International, Inc. (with PFD)
Journal/Conference:
Nucon Bulletin 10B8-6/92
Date: 6/92
Author(s):
National Environmental Technology Applications Corp.
Title:
BRAYCYCLE Solvent Recovery System
Journal/Conference:
Environmental Product Profiles
Date: 1/93
Author(s):
NUCON International, Inc.
Title:
BRAYSORB A Process By NUCON International, Inc. (with PFD)
Journal/Conference:
Bulletin 10B7-6/92
Date: 6/92
Author(s):
DOE Office of Industrial Technologies
Title:
Brayton Cycle Heat Pump Recovers Solvents
Journal/Conference:
Industrial Innovations
Date: 11/92
NTIS/Document Number(s):
DOE/CH 10093-118
Author(s):
Enneking, J.C.
Title:
Brayton Solvent Recovery Heat Pump Technology Update
Journal/Conference:
Industrial Energy Technology Conference
Date: 9/93
Author(s):
USDOE Office on Industrial Technologies
Title:
Brayton-Cycle Solvent Recovery Heat Pump
Journal/Conference:
Office of Industrial Technologies "Technical Brief"
Date: November 1994
NTIS/Document Number(s):
DOE/CH10093-251
Author(s):
Kovach, J.L.
Title:
Decoupled Solvent Adsorption Brayton Cycle Regeneration Systems
Journal/Conference:
NUCON Technical Paper 288
Date: 1991
Author(s):
Enneking, J.C., NUCON; S. Priebe, EG&G Idaho
Title:
Environmental Application of Brayton Cycle Heat Pump at Savannah River
Journal/Conference:
Industrial Heat Pump Conference
Date: 10/93
Author(s):
Fox, Bryce
Title:
Heat and Liquid Recovery Using Open Cycle Heat Pump System
Journal/Conference:
Patent 4,295,282
Date: 10/81
Author(s):
Kovach, J.L.
Title:
Recovery of Condensable Organic Compounds From Inert Gas Stream
Journal/Conference:
Patent 5,152,812
Date: 10/92
Author(s):
Enneking, J.C.
Title:
VOC Emission Control with Brayton Cycle Pilot Plant Operation
Journal/Conference:
Industrial Energy Technology Conference
Date: 9/92
Author(s):
Fox, Bryce
Title:
Vapor Recovery Method and Apparatus
Journal/Conference:
Patent 4,480,393
Date: 11/84
Author(s):
Scheihing, Paul E., DOE
Title:
Vapor Recovery and Recycling of Methylene Chloride from Painting
Author(s):
Electric Power Research Institute
Title:
Volatile Organic Compound Recovery by Brayton Cycle Heat Pump
Date: 09/93
NTIS/Document Number(s):
EPRI TR-102130
Author(s):
Kovach, J.L.
Title:
Water Removal From Humid Gases Laden With Organic Contaminants
Journal/Conference:
Patent 5,163,980
Date: 11/92