You can use rotary dryer. We can be your supplier for this dryer. We can manufacture rotary dryer in Canada or in China.

huanglong@hotmail.com ■

Give us a call at Air Preheater Company, Raymond Operations we make both a rotary and flash system .

See our equipment at www.airpreheatercompany.com and contract us email at info@airpreheatercompany.com ■

Latest technology.

Large scale trials now complete.

High effieciency.

www.dbaglobal.net

More information e-mail tlearey@dbaglobal.net ■

Drying of Coal using micro wave radiation

We carried out many tests, using micro wave for heat treatment of coal.

Ergun , H. , D. Wagener , H. Fach : Heat Treatment of Coal.

UK Patent Application GB 2017744 A , Patent Office London, 10. 10. 1979 .

Ergun , H. , D. Wagener , H. Fach : Heat Treatment of Coal.

Canadian Patent , C. R. Cl. 202-4 ,CA 1135652 , Patent Office Ottawa ,16. 11. 1982 .

It is also possible to carbonize the coal by using micro waves..

[ ■

HOLO-FLO units have been used for drying coal. Very efficient and less downtime. Compact and very easy to operate. HOLO-FLO are hollow flight screws allowing the heat transfer medium to circulate inside the flights and jacketed housing. The heat exchange is indirect and therefore there is no contamination. Coal can be tricky to handle at high temperature. However, our experience in handling coal allow us to incorporate our design to help minimize or eliminate flow problems at high temperature. If you are interested, please send us your application info at jiggger2003@yahoo.com and we can provide you with sizing and price estimates. P.S. HOLO-FLO units are also sometimes used as pyrolyzer. ■

Is simply blowing your hot flue gas though the 5 tph crude enough for your purposes? You have to boil off 12% of 5tph, although the water is denser. So lets say you have to get rid of about, your input, 600kg of steam.

Do some preliminary enthalpy sourcing to see if your gas can provide. As the previous replies clearly affirm...nobody is going to admit that their pride & joy equipment is some crude kind of dryer. ■

Dear Learey

Is the MW dryer aplicable for belt conveyor (coal) flow about 1500t/h and speed 2 m/sec ? or does the system need special conveyor or special condition? and how much maximum conveyor capacity or speed or width can be handled?

Assume Coal TM 30% with Free Moisture 18% and Inherent Moisture 12%, We need reduce TM from 30% to 15%, what kind the composition of 15% remain mosture after MW dryer?

Thanks

Huri Amri ■

The systems needs own conveyor belt or multiple conveyor belts depending on the effieciency of the coal, amount of moisture wanting to be reduced. As a generailisation, it takes 0.3 - 0.45kw per litre removed depending on the coal. The system generally operates at 15 - 25tph depending on the duty, so you need to add streams to get to your total throughput.

Suggest you e-mail me seperatly with more detail. tlearey@dbaglobal.net ■

The cost of revoming water from coal ranges from 0.2 - 0.4 kw per litre removed, depending on if the water removed is free moisture or inherent moisture. The tonnage though the Drycol unit depends on the amount of water wanting to be removed. So the number of machines and capital cost is very dependent of the job being done.

First step is testwork on the coal to determine the efficiency of the water removal. Anyone who tries to calculate the economics without test work could be 200% out.

Happy to talk with anyone regarding test work programs.

www.dbaglobal.net ■

Huri,

I suggest that you remove as much free water as you can by building a sieve bend into a fixed tripper. After that you can consider removing some more water by the means suggested above.

There is a very wide line between dewatering & drying. eg if you threw more water at the mixture until you could filter it you could get the moisture down quite low..but who would do such a thing?

1500 tph @ 2m/s is a fair throughput & it seems that a simple mechanical screen would greatly help while the sludge is already on a fair sized belt. Most of your free water will have percolated towards the belt so if you can arrange a sympathetic trajectory the sieve bends can get rid of quite a lot of it very conveniently.

www.ludomin.com is a good starting place to look up.

Incidentally I have just realised that a sieve bend would be an excellent way to remove ponding troubles from stockyard belts.

Are the Florida & Dynasty Clubs still thriving in Merak & Cilegon? ■

John,

Not sure if you appreciated that the coal is not a sludge, it just comes out of the ground at 30% moisture. It would not free drain any water. Even a centrafuge would do very little.

For this type of coal, most of the moisture is 'interstitial' and 'inherent'...so there is only two options.

1. Thermal dryer

2. Drycol microwave unit

Both expensive, but the upside with microwave is the reduced operationg cost, coal loss and the reduced fire risk.

Trevor. ■

I developed clean up systems for 8000 tph coal carrying lines at Selby coalfield in the UK in 1985 & reckon I am quite familiar with wet coal. I have seen water gushing out of the closed side observation doors & experienced dribblings conveyor failures from overloading. Those were 17% total moisture conditions!

18% free moisture is quoted! That is 4.5 tpm.

Coal to Suralaya has not just come out of the ground; it has been stored in the rain in Kalimantan; lightered by barge onto the ship ( or possibly barged to Merak direct ) & then stored out in tropical monsoon conditions awaiting feed to the boiler bunkers.

If the boilers had been designed to burn 30% moisture r-o-m then there would not be a problem now. My contention that a sieve bend can drop the moisture to almost acceptable limits, for further treatment, is quite valid: at least as valid as proposing 100 - 60 stream segments!

Huri, If you make a coarser blend you will get slightly less catchment water. ■

Your mention of Suralaya caught my eye because I used to visit there from time to time when I was with the company that provided the first 3700 MWe of boilers. I was not aware of a moisture problem.

I would appreciate an informed opinion regarding Turkish Lignite reported to have 21.5% ash and 52.5% moisture. What are the practical measures for reducing moisture to a reasonable level? Or is the 52% moisture a red herring?

My scepticism results from PLTU Banjarmasin project, which was going to burn Kalimantan coal and was specified for 50+% moisture, but I don't know if it ever got that wet. ■

Can anyone provide some advice on drying of Turkish Lignite? Reported properties include 52% moisture and 22% ash, which I have assumed is on an as-received basis, given the heating value of only 1130kcal/kg (LHV).

Does anyone have any details on the fluidized bed dryer that was used at Coal Creek in Nebraska, USA? ■

Dear Mr. Yash,

Irrespective of which drying technology you use, you will surely benefit from online moisture analysis. Our Australian Principal CALLIDAN is the world leader in Online Moisture Analysis and manufactures and markets online moisture analysers that use microwave technology. Please feel free to visit our principal's site at www.callidan.com for more information. Regards

Jitendra RoyChoudhury

Business Development Manager

Salva Resources

Mob: +9198300 44856

Mail: j.roychoudhury@salvaresources.com

Web: www.callidan.com ■

Dear yash,

Please specify if the moisture you asre talking about is surface moisture or total moisture of coal. If you are specific about surface moisture we could suggest using a centrifugal dryer to reduce the moisture of coal. If the total moisture has to be reduced to levels specified by you then only thermal drying would be of help. You might have to work out the cost of heating. Generally for quantities such as 5TPH we would stock the coal in a dry place near a source of heat like a kiln which can redeuce the moisture content of coal virtually free of cost.

We would suggest you to let us know the moisture and maybe we have a solution.

With regards

Sandeep ■

LF Pumping guarrantees savings over any traditional drying methods. The LamiFlo System is the true environmental drying system as we don't use natural resources to generate heat, thus offering massive operating savings, with a reduced carbon footprint.

With energy prices set to rise over the next 5 years, we know this system will be of great interest to you, either as a pre-dryer for your existing drying systems or as a standalone drying, pumping or material handling unit.

The key Points associated with this unique environmental system, compared to any known rotary, ventura, vibrating fluid bed, or static fluid bed drying systems for materials are:-

•Guaranteed energy savings, as there is no requirement for any gas, gas/oil or diesel fuels, to generate heat source to dry materials.

•Reduced carbon footprint.

•Operational advantages throughout the transportation, drying, and delivery process.

•Compact size.

•Guaranteed Low maintenance costs.

•Minimal disruption of integrating system in to current process line.

•Liquids, sludges, and aggregates up to 75mm.

•Bespoke systems can dry sand from 60% moisture content down to 0.3%.

•Bespoke systems can handle up to 500 tonnes per hour.

What materials can be dry, pump, or material handle? http://lfpumping.com/material-handling.php

We are confident that this system offers to you the very latest cutting edge technology, packed with financial and delivery savings. We look forward to discussing all your transporting, drying, crushing, and grading applications. ■

I too nee your mail id so that I can forward you some interesting notes on that. ■

250 tonnes per hour capacity, (LF Pumping canhandle from 1 tonne to 500 tonnes per hour) with coal moisture content of 18% to be reduced down to a target moisture content of 3%.



LamiFloTM Coal Drying

1. Energy Usage (MJ) / tonne 6.34

- Gasoil (litres) / tonne NA

- Electricity (kW) / tonne1.76

2. Operating Costs (£) / tonne*£0.12

3. Carbon Emissions (kg) / tonne0.94 kg

Based on £0.07 per kWh.

The LF Pumping Coal Dryer will move coal up to 500 metres and dry in the same process, crushing is also available with this dryer.

www.lfpumping.com ■