Steady State Analysis of Heated Soil Vapor Extraction Process with Air Sparging

2006 ◽  
Author(s):  
Ryo Amano ◽  
Pradeep Mohan Das ◽  
Jay Jatkar
Keyword(s):  
Steady State ◽  
Extraction Process ◽  
Soil Vapor Extraction ◽  
Air Sparging ◽  
Vapor Extraction ◽  
Steady State Analysis ◽  
Heated Soil ◽  
State Analysis

Steady State Analysis of Heated Soil Vapor Extraction Process With Air Sparging

2005 ◽  
Author(s):  
P. M. Mohan Das ◽  
R. S. Amano ◽  
T. Roy ◽  
J. Jatkar
Keyword(s):  
Extraction Process ◽  
Soil Vapor Extraction ◽  
Air Sparging ◽  
Saturated Zone ◽  
Vapor Extraction ◽  
Combined System ◽  
Discrete Phase Modeling ◽  
Discrete Phase ◽  
Time Required ◽  
Heated Soil

Heated Soil Vapor Extraction (HSVE), developed by Advanced Remedial Technology is a Soil remediation process that has gained significant attention during the past few years. HSVE along with Air sparging has been found to be an effective way of remediating soil of various pollutants including solvents, fuels and Para-nuclear aromatics. The combined system consists of a heater/boiler that pumps and circulates hot oil through heating wells, a blower that helps to suck the contaminants out through the extraction well, and air sparging wells that extend down to the saturated region in the soil. Both the heating wells and extraction wells are installed vertically in the saturated region in contaminated soil and is welded at the bottom and capped at the top. The heat source heats the soil and the heat is transported inside the soil by means of conduction and convection. This heating of soil results in vaporization of the gases, which are then absorbed by the extraction well. Soil vapor extraction cannot remove contaminants in the saturated zone of the soil that lies below the water table. In that case air sparging may be used. In air sparging system, air is pumped into the saturated zone to help flush the contaminants up into the unsaturated zone where the contaminants are removed by SVE well. In this analysis an attempt has been made to predict the behavior of different chemicals in the unsaturated and saturated regions of the soil. This analysis uses the species transport and discrete phase modeling to predict the behavior of different chemicals when it is heated and absorbed by the extraction well. Such an analysis will be helpful in predicting the parameters like the distance between the heating and extraction wells, the temperature to be maintained at the heating well and the time required for removing the contaminants from the soil.

Transient Analysis of Heated Soil Vapor Extraction Process With Air Sparging

2005 ◽  
Author(s):  
P. M. Mohan Das ◽  
R. S. Amano ◽  
T. Roy ◽  
J. Jatkar
Keyword(s):  
Extraction Process ◽  
Soil Vapor Extraction ◽  
Air Sparging ◽  
Saturated Zone ◽  
Vapor Extraction ◽  
Combined System ◽  
Discrete Phase Modeling ◽  
Discrete Phase ◽  
Time Required ◽  
Heated Soil

This paper presents the Heated Soil Vapor Extraction (HSVE) that has gained significant attention during the past few years. HSVE along with Air sparging has been found to be an effective way of remediating soil of various pollutants including solvents, fuels and Para-nuclear aromatics. The combined system consists of a heater/boiler that pumps and circulates hot oil through heating wells, a blower that helps to suck the contaminants out through the extraction well, and air sparging wells that extend down to the saturated region in the soil. Both the heating wells and extraction wells are installed vertically in the saturated region in contaminated soil and is welded at the bottom and capped at the top. With this technology the soil is heated by means of conduction and convection. This heating of soil results in vaporization of the gases, which are then absorbed by the extraction well. Soil vapor extraction cannot remove contaminants in the saturated zone of the soil that lies below the water table. In that case air sparging may be used. In air sparging system, air is pumped into the saturated zone to help flush the contaminants up into the unsaturated zone where the contaminants are removed by SVE well. In this analysis an attempt has been made to predict the behavior of different chemicals in the unsaturated and saturated regions of the soil. This analysis uses the species transport and discrete phase modeling to predict the behavior of different chemicals when it is heated and absorbed by the extraction well. Such an analysis will be helpful in predicting the parameters like the distance between the heating and extraction wells, the temperature to be maintained at the heating well and the time required for removing the contaminants from the soil.

A Study of Soil Remediation by Vapor Extraction System and Air Sparging

2004 ◽  
Author(s):  
T. Roy ◽  
R. S. Amano ◽  
J. Jatkar
Keyword(s):  
Heat Source ◽  
Soil Remediation ◽  
Unsaturated Zone ◽  
Fine Sand ◽  
Soil Vapor Extraction ◽  
Extraction System ◽  
Air Sparging ◽  
Saturated Zone ◽  
Vapor Extraction ◽  
Heated Soil

Soil remediation by heated soil vapor extraction system and air sparging is a new technology developed by Advanced Remedial Technology, Inc. The areas around chemical companies or waste disposal sites have been seriously contaminated from the chemicals and other polluting materials that are disposed off. The process developed by Advanced Remedial Technology, consists of a heater/boiler that pump and circulates hot oil through a one-inch pipeline that is enclosed in a six-inch pipe. This six-inch pipe is vertically installed within the contaminated soil up to a certain depth and is welded at the bottom and capped at the top. Pea gravel or fine sand fills the six-inch pipe and thus acts as a heat transfer medium. The number of heat source pipes and the extraction wells depends on the type of soil, the type of pollutants, moisture content of the soil and the size of the area to be cleaned. The heat source heats the soil, which is transported in the interior part of the soil by means of conduction and convection. This heating of soil results in vaporization of the gases, which are then driven out of the soil by the extraction well. The extraction well consists of the blower which would suck the vaporized gases out of the system. Soil vapor extraction cannot remove contaminants in the saturated zone of the soil that lies below the water table. In that case air sparging may be used. In air sparging system air is pumped into the saturated zone to help flush the contaminants up into the unsaturated zone where the contaminants is removed by SVE well. In our present study we concentrated on modeling one Heated Soil Vapor Extraction System with air sparging and predicting the behavior of different chemicals in the saturated and unsaturated zone of the soil. This analysis uses the species transport and discrete phase modeling to predict the behavior of different chemicals when it is heated and driven out by the sucking well.

Analysis of Single Buffer Random Polling System With State-Dependent Input Process and Server/Station Breakdowns

2018 ◽  
Vol 9 (1) ◽  
pp. 22-50 ◽  
Author(s):  
Thomas Y.S. Lee
Keyword(s):  
Steady State ◽  
Linear Model ◽  
Repair Process ◽  
Polling System ◽  
Steady State Analysis ◽  
Relaxation System ◽  
Polling Model ◽  
State Dependent ◽  
Non Linear ◽  
State Analysis

Models and analytical techniques are developed to evaluate the performance of two variations of single buffers (conventional and buffer relaxation system) multiple queues system. In the conventional system, each queue can have at most one customer at any time and newly arriving customers find the buffer full are lost. In the buffer relaxation system, the queue being served may have two customers, while each of the other queues may have at most one customer. Thomas Y.S. Lee developed a state-dependent non-linear model of uncertainty for analyzing a random polling system with server breakdown/repair, multi-phase service, correlated input processes, and single buffers. The state-dependent non-linear model of uncertainty introduced in this paper allows us to incorporate correlated arrival processes where the customer arrival rate depends on the location of the server and/or the server's mode of operation into the polling model. The author allows the possibility that the server is unreliable. Specifically, when the server visits a queue, Lee assumes that the system is subject to two types of failures: queue-dependent, and general. General failures are observed upon server arrival at a queue. But there are two possibilities that a queue-dependent breakdown (if occurs) can be observed; (i) is observed immediately when it occurs and (ii) is observed only at the end of the current service. In both cases, a repair process is initiated immediately after the queue-dependent breakdown is observed. The author's model allows the possibility of the server breakdowns/repair process to be non-stationary in the number of breakdowns/repairs to reflect that breakdowns/repairs or customer processing may be progressively easier or harder, or that they follow a more general learning curve. Thomas Y.S. Lee will show that his model encompasses a variety of examples. He was able to perform both transient and steady state analysis. The steady state analysis allows us to compute several performance measures including the average customer waiting time, loss probability, throughput and mean cycle time.

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