Dear sirs,

We are TNPL Environmental Co.,Ltd China

our company job is powder material handling by dense phase pneumatic conveyance and silo equipments. Would you please

be information more detail such as how much point of material out let, if the material out-let from bag filter ect.

our company E-mail: pneutj@263.net ■

Dear Mr. abhik

As we understand, pneumatic conveying of dryed petcoke and limestone mixture for about 200m, does not occur any problems in your plant.

The conveying of wet slurry by dense or dilute-phase high-speed pneumatic systems cause some layers onto the inside wall of the pipeline.

The conveying will take about 50-55 seconds to blow the material through the 1500 m line.

Fact is, that wet mixtures of bulksolids with 10-18% humidity can be considered as bulksolids, over 18%-20% humidity they turn to slurries.

Anyway, you dont reach the chemical reaction-time of given few minutes during conveying in the pipeline, but the standing growing layers stop the conveying in a short time.

We have seen this process in several pneumatic conveying systems for detergents and limestone-based gas-cleaning systems for powerplants.

By this way hydraulic or mechanical conveying seems to be more advantageous, if the mixture is really a a slurry. ■

Subject: Pneumatic Conveying of Pet Coke Ash

Mr. Wohlbier:

On behalf of Matrix Engineering, I wish to express my appreciation for your questions concerning the conveying of Pet Coke Ash. The material you are working with is primarily a combination of calcium sulfate (CaSO4) and free lime (either as CaCO3 or CaO). Once the material is hydrated, you have formed gypsum, which is calcium sulfate dehydrate (CaSO42H2O). As you have described in your note, the holding silo is 200 meters (650 ft) away from the process, and the ash pond is 1.5 km (0.93 miles). Depending on the amount of ash to be conveyed, the distance to the storage silo is not excessive, and a pneumatic conveying system could be designed for this specific application. As far as the ash pond is concerned, the 1.5 km is a rather lengthy distance, but what you have to be concerned about is the elevation. There should be sufficient head on the line to allow the material to drain completely into the ash pond. Ash from the pond should not back up into the outlet of the line, as this will allow the material to set up over time and plug the outlet. You should also have sufficient clean-outs along the line that would allow cleaning without having to excavate and break into the line. This is usually accomplished by installing a “Y” clean-out in the line. The “Y’s” should be alternated along the length of the line to allow cleaning in both directions. The cleaning can be accomplished by using a high pressure water blaster with sufficient volume and velocity to remove the build up in the line once it has been broken up.

In looking at your fuel supply, I was wondering about the mixture of petcoke and lime. It seems that 80% lime stone and 20% petcoke would not provide sufficient heat input to your boiler. Are you adding an additional fuel, such as coal, oil, gas, etc? Since we are working with lime kilns that burn either oil or gas, our petcoke substitution rate is higher than 20%.

If you wish Matrix Engineering to look at this project, please provide specific information and we can discuss further. If we can be of further assistance, don’t hesitate to give me a call.

Best Regards,

Douglas W. Knott

Director Sales and Marketing

Matrix Engineering PLLC

112 Walter Jetton Blvd.

Paducah, Kentucky 42001

Ph. 270/442-5600, Ext. 205

Fax 270/442-0061

Cell 270/556-3408 ■