Several options come to mind

and as solar heat is technically free except for the cost of capturing it this option may be viable if land is not an issue.

Creating a very large solar hot box by splicing thousands of feet of black PVC water pipe together with grey PVC nipples and gear hose clamps creates a huge thermal mass by laying them on black plastic sheeting and securing the pipe in place with rebar bent in U shapes.

You would create huge thermal loop many miles long adding heat as it traveled through the pipe ending at the current drier where it would pass through a heat exchanger from L+M radiator and fan used to blow the drying air to the sand drier in a closed circuit air circulation system.

After the air passed through the L+M radiator sized for job it would return tot eh loop to be reheated.

You would need a centrifigal water pump that is rated for high temperature water 140 degrees fahrenheit or more and a small bladder tank to absorb pressure spikes from the water flow.

The system would require the installation of an home sized automatic water feeding valve and back flow preventer to add make up water lost as is done with a home radiant baseboard or floor loop pipe system.

The water pumping distance is not an issue assuming the land for the heat farm is flat

and the issues of volume per minute and pipe size will affect the size of the pump needed

and as the water is colder or cold on the return trip it is denser making it easier to pump.

Any large flat roof is an oven especially if one wishes to paint it black and lay steel pipe on it.

A large flat roof pianted black or a small one will create a huge thermal mass which is weather dependent of course.

The use of 1 inch victaulic grooved pipe joints and fittings would lend itself well to a thermal heat exchange method where the

loops could be a foot a part to create all that heat- but it would depend on the roofs strength entirely as to whether the added

weght of the piping and water in season could be tolerated.

The use of geothermal heat is another possibility by drilling creating a semi open loop geothermal heat sytem.

A bore hole woul be drilled 3,300 feet in bedrock using range 3 casing from the surface and when the hole is bottomed

you would lower temperature sensors to determine the earths temperature at that depth; on this side of the pond the

the air temperature in the salina salt No 6 seam at that depth is 120 degrees or more in abandoned open workings/tunnels

to see if the temperature is hot enough to heat water efficiently and transfer it to the surface.

After the desired depth is reached fresh water is pumped in the well to fill it if fresh water is not evident at the bottom of the bore hole.

Enough water is added to create a water column 3,300 feet high with the diameter of the casing pipe used which creates the hot water column.

The sucker rod pump is connected to the first pipe joint lowered into the well and additional pipe joints are added as the work continues until the desired depth is reached.

after the water pipe is installed and anchored to the wells casing at the surface the first sucker rod is attached with the check ball or piston used to pump the well water.

The sucker rods are added as the string is lowered until the job is completed and the small pump jack or rocking horse is mounted over the well casing and attached to the sucker rod.

The water is pumped by the pump jack within the second pipe to the heat exchanger/ radiator and returns to the well via gravity to begin it descent to the bottom to absorb heat again.

much simpler than deep well pumps as the motor is at the surface. the sucker pump has been used for 150 years now and is the pump of choice ofr oil wells too and

it uses a lot less energy to do its job depending on gravity to aid in pumping water or oil.

A dry geothermal well could be drilled if the rock is hot enough - a second pipe would be lowered inside the steel casing and cold air is delivered to the bottom of the hole with a forced draft

mine ventilating fan and a second fan is used to pull the lighter in weight heated air from the bottom of the bore hole through the wells annulus and delivering it to a furnace as preheated air or

to the drier is it is of sufficient temperature at the well head as long as the delivery piping is insulated.

lzaharis ■

About your sand,

Not many options short of using the semi open loop geothermal well with a rotary dryer using an L+M radiator for the forced air OR a drum drier with paddles sized to your desired capacity as is used with the white cane or beet sugar.

The installation cost of a gethermal semi open loop well is higher but the energy savings is immediate with or with out the use of deep ground heat where a geothermal hot air heating system will take the well water in the semi open loop

well of 1550 feet in depth and use the chilled water to create heat energy for the forced air drier OR a LAROX flat belt vacuum filter with the longer the filter belt the more moisture is removed with the pressure gradient created by the vacuum filter bed and the sand is dried with high efficiency due to the structure of the sand granuals and the vacuum filter pulling the water out of the sand with the filter curtain being the barrier at 4-800 denier fabric size.

The longer the plate filter the greater the efficiency and less total energy used to reduce moisture.

Using the semi open loop well to create chilled air in the heat exchanger which would be piped into the inlet air stream of the belt vacuum filters positive displacement rotary lobe blower which in turn creates a higher pressure gradient which increases the available energy as the air entering the blower inlet is colder and more dense which makes the blower deliver greater energy per cubic foot of inlet air used to create the pressure gradient required by the bed filter and reducing the cost to operate the bed filter at high tonnages. ■

Robert,

We would like to introduce LF Pumping Ltd, who offer the LamiFlo Sand dryer. This innovative, economic, environmentally friendly, and mobile if required, sand dryer, can easily reduce the moisture content, quoted below, of 100 tonnes of sand in an hour. We have developed a system which could handle up to 500 tonnes per hour.

The LamiFlo system is so economic to run that we can supply the dryer, and the running of the unit for less than half the running cost of a ventilex or rotary drum, when expressed as a rtae per tonne.

As you have said energy costs are only going one way, up, so to be less reliant on energy intensive dryers is a must in todays competitive world, saving money and carbon impact.

http://www.lfpumping.com ■

Originally Posted by Robert Street

i am looking for a sand dryer. I have used rotary and ventilex before, however i have not purchased a sand dryer for 8 years, and I was interested to see whether they are other technologies available.

i am concious of running costs, as when you consider the futures market for all sorts of fuels, they are only going one way...up.

Could anyone offer any advice for equipment, and approximate running costs?

Tonnage per hour 100 tonnes

Moisture content 10 - 12%

Target Moisture content below 1%

What is the most efficent sand dryer? I would be happy to pay more for the equipment, and cut down on the running costs.

Robert,

Sounds like a vibrating fluid bed application. We have experience with sand drying with cooling zone and recirculation. Please contacrt us at gloverd@btconnect.com. We would be very interested in quoting once all details are available.

Regard

Dave Glover ■

We have just updated our website with our latest information regarding the LamiFlo Sand Dryer showing that we can dry & material handle with a running cost of less than $1.00 per tonne, and producing less than 5kg of CO2 per processed tonne.

The revolutionary LamiFlo Sand Dryer offers low maintenance, along with static and mobile options for up to 500 tonnes per hour. http://www.lfpumping.com/sand-drying/

If we can be of any assistance please feel free to contact L F Pumping (Europe) Ltd. http://www.lfpumping.com ■