#124 - Particulate Removal from Sample Gases under Different Conditions

We have been using the heated filter concept for many years as an efficient way to extract a dusty gas sample and filter it prior to transportation to a gas analyzer. One of the reasons why we filter dusty applications at the extraction point is to avoid development of a dust / condensate slurry which would plug the sample tubing in and after the filter.

Our customers have had various combinations of conditions that have given rise to different configurations of heated filters as follows:

1. The standard heated filter is attached to a flue gas duct using a mounting flange. This configuration is suitable for samples at basically atmospheric pressure. The installation must be in a non-hazardous area. The cabinet requires a supply of instrument air or nitrogen to allow a blowback of the filter and the probe. This pushes the accumulated dust back into the flue gas duct.
2. The standard heated filter is also available in a hazardous area configuration. The heater is rated for hazardous areas and the electrical contacts are sealed in a small explosion-proof junction box.
3. Some high pressure processes, such as Direct Reduction of Iron (DRI), also require dust removal before gas analysis. We can provide a high pressure configuration of the heated filter system. However, this system does not allow blowback because of the high pressure in the process.
4. A version of the high pressure configuration is available that is suitable for hazardous areas.
5. Some sample points on a DRI process are also quite hot. It may be necessary to cool the sample slightly before it enters the filter. We can provide water-cooled spool pieces that are mounted between the probe and the filter valve.
6. We have also developed a vertical design which can be mounted on a duct or silo where the extraction probe is required to point downward into the gas atmosphere.

NOVA Heated filter system mounted vertically on a
process application at one of the US National Labs.
(Not our standard configuration, but worked
very well for this project.)

For information on these and other gas analyzer systems, give Mike or Dave at Nova a call, or send us an e-mail.

1-800-295-3771

sales at nova-gas dot com

websales at nova-gas dot com

http://www.nova-gas.com/

https://twitter.com/NOVAGAS

http://www.linkedin.com/company/nova-analytical-systems-inc-

http://www.tenovagroup.com/

#123 - Borehole and soil gas analysis - Part 1

Borehole Gas Analysis

A borehole is basically a thin shaft that extends into the ground vertically or horizontally. There are numerous purposes for drilling boreholes including water, petroleum, or gas extraction. A borehole may be required for environmental or geological investigations.

We have had numerous requests in the past from mining companies who want to test the gas atmosphere in boreholes extending vertically into the ground. The site may be a prospective mine, a depleted mine, or a critical area of interest near the mine. A portable instrument is required because there may be several boreholes on a site. The technician travels to each hole to obtain a series of gas analysis readings.

For gas analysis, there will usually be a tube bundle extending to different depths into the shaft. By attaching a gas analyzer to each of the tubes, an atmosphere vs. depth profile can be obtained of the shaft. This information can be indicative of soil condition, microbial activity, or some other investigated parameter.

We have frequently sold the Model 309 Portable O2 / CO2 analyzer for this application. Because some of the samples will be pulled up from deep into the borehole, we can install a heavy duty pump into the instrument. We usually incorporate a bowl filter of some kind at the sample inlet to capture any water that may come up with the gas.

Ore Sample Gas Analysis

In some cases, analysis might be required for a rock or ore sample that is brought to the surface for study. Because gas does not normally come off of a rock sample in large constant volumes, the sample will be sealed into a canister.

Inlet and outlet ports on the canister allow the gas analyzer to be connected via flexible tubing. The outlet port on the canister is connected to the inlet port of the analyzer. The inlet port of the canister is connected to the vent of the analyzer. The gas flows in a closed loop as shown in the picture below.

Valves and tubing can be arranged to minimize the amount of diluting air that is introduced into the canister atmosphere.

Ground Level Gas Analysis

We have also had requests for analyzers for ground level gas analysis. The procedure may consist of a domed and sealed cover over a section of soil. The cover has a tube fitting which may be connected to a gas analyzer.

The gas analyzer will pull a sample from the airspace between the cover and the soil. Because a limited volume of air exists between the cover and the soil, a pressure reduction will develop as the analyzer pulls more sample. The heavy duty pump can continue to pull so that a small sample of soil gas can eventually be obtained. We suspect that these conditions of sample extraction are not ideal for high accuracy readings. However, some users have reported that the resulting readings are enough to satisfy the requirements of their soil investigations.

Link to the Model 309.

Other interesting links:

http://en.wikipedia.org/wiki/Tailings

https://en.wikipedia.org/wiki/Borehole

https://en.wikipedia.org/wiki/Kola_Superdeep_Borehole

NOVA Analytical Systems

1-800-295-3771

sales at nova-gas dot com

websales at nova-gas dot com

http://www.nova-gas.com/

https://twitter.com/NOVAGAS

http://www.linkedin.com/company/nova-analytical-systems-inc-

http://www.tenovagroup.com/

#122 - Nova mentioned in Tenova newsletter

Nova mentioned in Tenova newsletter April issue.

Check us out on page 12.

http://www.tenovagroup.com/tenova-news.php

#121 - Boyan Slat’s Ocean Clean-up Idea

Gyres are large systems of rotating ocean currents. 

There are five major oceanic gyre systems on earth:

Indian Ocean Gyre

North Atlantic Gyre

North Pacific Gyre

South Atlantic Gyre

South Pacific Gyre

There are also several large floating garbage patches that are blighting this world’s oceans. The debris consists mainly of plastic particles, packaging, and containers of various sizes. Most of the garbage originates from land-based human activities and is washed out to the ocean by rivers and other flowing water-ways. Much of the debris eventually accumulates in the gyres mentioned above.

This problem has always annoyed me immensely because humankind has expended enormous amounts of time, energy, technology, and money extracting riches from the world’s oceans. For example, large fishing vessels roam the seas capturing marine life in giant nets. However, using the same or similar technology to clean up our oceanic garbage patches has always been deemed financially or technically prohibitive. The excuses always seem to sound hollow when you think about all of the ways that we can capably extract things from the water.

An ocean clean-up idea originating in 2011 from two students named Boyan Slat and Tan Nguyen offers some potential feasibility. Although the feasibility studies have not been completed, it is an idea that will at the very least stimulate good discussion and general awareness of this problem. One reason why awareness of this problem is low is that there are few visual images available. The garbage is spread out over millions of square kilometers and is not striking in terms of photographic imagery. Of course, there are many images and examples of shoreline pollution as shown above.

The clean-up concept consists of large anchored booms that can be placed in the radial path of the gyre current flows. The booms are arranged in a “V” shape which will funnel the floating debris into a collection platform. The gyres are very large, the general speed is low, and the collecting action is primarily at the surface of the water. It is therefore unlikely that marine life even down to the plankton level will be extracted or harmed along with the debris.

Feasibility studies are underway and they are making good progress on some preliminary results that look promising. A team of engineers, modelers, external experts, and students are in the process of testing some of the initial assumptions that were made. They are advising optimistic caution until more results are obtained.

The oceanic garbage issue is a kind of distributed waste stream problem that we all share collective responsibility for. The millions of candy wrappers and plastic water bottles shown on the shoreline above - where do they all come from? It isn't a single traceable point source. These items emerge into the environment every time a person tosses a piece of garbage on the ground or in the water without thinking about where it will end up. Holding on to the garbage for another few minutes until we can put it into a recycling bin or a garbage can, will at least help direct it into a treatable waste stream and keep it out of the immediate natural environment.

That would make Boyan Slat's idea unnecessary. I'm sure he wouldn't mind. 

Edit Sept 2014: We have since done an update to this post here.

Links

http://www.boyanslat.com/plastic/

http://www.boyanslat.com/TEDx/

http://en.wikipedia.org/wiki/Ocean_gyre

All pictures obtained from Boyan Slat’s website except for ocean gyres map from Wikipedia.

#120 - Rapid Train Loading Systems by Tenova Takraf

I’ve always loved trains. Perhaps it’s the scale and power of the equipment. Perhaps it’s the history and variety of the industry.

A couple of historical highlights that appeal to me are: *

Regarded by many as The Ultimate Steam Locomotive of All Time -
the vast "Niagara" 4-8-4 of the New York Central Railroad.

The first main line diesel-electric in North America (Canadian National),
No. 9000, built in 1929, and split into two units for operation
following trial running. 

The Hiawatha Express
Top: Class A 4-4-2 No. 1 near Dearfield, Illinois, 1939.
Above: Class F7 No. 101 darkens the sky over Milwaukee
as it pulls with Train No. 101, the streamlined
13-coach "Afternoon Hiawatha".

The Swedish rod-drive triple-unit Class "Dm3" electric locomotives can
produce more than 200,000lb of tractive effort.

June 13/2013 - A part 2 to this post was added here - http://nova-gas.blogspot.ca/2013/06/126-takraf-train-post-was-big-hit.html

Speaking of trains, Tenova Takraf makes loading systems for railway cars. Tenova TAKRAF Rapid Rail Loading Systems use the flask loading system to load particulate material into moving trains:

• loading at rates of up to 8,000 t/h.
• handling a variety of rail wagons of different capacities and types.
• loading with accuracies, which meet most countries’ statutory requirements.
• allowing for a variation in material size and bulk density.

May 24, 2013 - More pictures added to this post; shown below.

The system pre-weighs each wagon load prior to depositing the load into the moving wagon. An optional extra is the integrated calibration system, which operates via a SCADA system. Flow of material outside the storage bin and weigh flask is controlled by single-pass radial gates. These are actuated hydraulically by a system that ensures that the gates close fully without jamming.

The Tenova TAKRAF Profile Chute system, through which material flows into the wagons, is self adjusting and allows for differences in the heights of wagons to ensure the correct profile of material in the wagons. The chute is designed to minimise potential dust emissions during loading.

The Profile Chute is fail-safe in the event of any electrical or hydraulic power failure. The Chute will automatically move out of the way of rolling stock entering the rapid rail loading system bay.

SELF LEARNING CAPABILITY

The Tenova TAKRAF Rapid Rail Loading System incorporates a programmable logic controller (PLC) and computer controlled measurement system, which has a learning capability.

As the first few wagons are loaded, the system assesses the effect of the loaded material’s density and flow characteristics; the latter is affected by particle size, moisture, temperature, etc. The system automatically accounts for prevailing conditions and loads subsequent wagons to a high level of accuracy.

CONTROL SYSTEMS

Tenova TAKRAF Rapid Rail Loading Systems are equipped with user friendly computer control, information and records systems.

The accurate loading capability avoids penalties because:

• individual wagons are not overloaded.
• axle distribution requirements are met.
• wagons are loaded to the correct height.

The control system is based on client specified hardware and Windows™ based software allowing:

• overall SCADA control of the operation.
• automatic validation of truck numbers as they are entered into the SCADA system.
• visual monitoring of operations through closed circuit television systems.

Several optional facilities can be supplied, including:

• uninterrupted power supply for computer systems.
• communication networks to the other computers, PCs or mainframes.
• communications with other weighing equipment on the plant to control reclaim operations.
• built-in mass calibration systems to simplify calibration.

Tenova TAKRAF

Tenova Mining & Minerals (Pty) Ltd

1 Kramer Road

Bedfordview

Johannesburg

PO Box 75996

Gardenview, 2047

South Africa

phone +27 11 201 2300

fax +27 11 455 4547

enquiries.TMM@za.tenovagroup.com

TAKRAF GmbH

Torgauer Straße 336

04347 Leipzig

Germany

phone +49 341 2423 500

fax +49 341 2423 510

sales@takraf.com

Nova Analytical Systems
1-800-295-3771

sales at nova-gas dot com

websales at nova-gas dot com

http://www.nova-gas.com/

https://twitter.com/NOVAGAS

http://www.linkedin.com/company/nova-analytical-systems-inc-

http://www.tenovagroup.com/

* Scanned from The Illustrated Directory of Trains of the World by Brian Hollingsworth © Salamander Books Ltd., 2000. Excellent rail resource with pictures and short summary of historic and modern locomotives worldwide.