Slurry flusher cleans up with ease

One man to milk, feed and clean 200 cows may seem a pretty tall order. But at Fields Farm, near Middlewich, Cheshire, that’s how the job is done.

Apart from weekend relief, Les Furber is the sole employee on the farm and is responsible for managing the herd plus 150 followers.

An integral part of this one-man system is an automated slurry flushing system for the farm’s parlour and cubicle housing, which means Mr Furber does not have to spend hours each week scraping slurry passageways.

“The cow housing and parlour were built on a greenfield site, so every effort was made to ensure that the best slurry system possible was installed,” he says.

“Without it we would have had to employ an extra person.”

The slurry flushing system is a self-contained unit which – for its main flushing operation – uses water that has already been used.

It is passed through a separator to take out the solids and the resulting “dirty” water is pumped back into to the system.

An 8m tall, 60,000-litre tank is used to store the dirty water and provide the pressure for flushing the collecting yard and the passageways in the cubicle housing.

A separate 40,000-litre tank holds clean water and is used to flush the parlour.

This water has been collected from the building roofs and stored in a reservoir.

An essential part of the system is the 1:50 slope running through the building, with the parlour at the top end followed by a collecting yard and then the cubicles with their passages also running down the slope.

A timer can be set for a flush to take place at required intervals, and at the start of the flushing three valves are opened remotely by releasing the compressed air which holds them shut.

This releases 12,000 litres of water, which gushes through the parlour, in about 20 seconds.

Further down the building, valves on a separate timer are opened to release a similar amount of dirty water into the collecting area. Similarly, at the top of each of the four passageways, valves open to flush these areas clean.

At the bottom of the slope water is directed into a holding tank from where it flows into the separation area.

Two separators work about six hours a day to remove the solids from the liquid.

The solids are stacked accordingly and the dirty liquid is allowed to flow into a lagoon from where it is pumped back into the main header tank at the top of the slope.

After the water has drained clear of the flushed areas the concrete is almost spotless, which is reflected in the overall cleanliness of the cows.
“There is no doubt that the cows are cleaner and their feet are in better condition,” says Mr Furber.

“And we don’t get any sprained limbs from cows slipping over on greasy floors.”

To achieve such a high flow rate of water, 300mm (12in) diameter piping is used throughout the system.

The release valves are little more than manhole covers which lift when the compressed air sealing them flush with the floor is released.

Despite the torrent of water flowing though the building every six hours, the cows appear totally untroubled.

“They soon get used to it and, compared with a tractor and yard scraper or even an automatic passageway scraper, the water is no hindrance at all,” he says.

“Best of all, it only takes about 30 seconds from start to finish and does a better job.”

As for running costs, Mr Furber estimates the electricity to power the pumps and the separators at about £16 a day.

There are next to no maintenance costs, he says.

About three times a year, when the water has become totally saturated with small particles which the separators cannot remove, the dirty water is drained out of the system and replaced with “clean” water from the rainwater supply.

The cost of installation is difficult to gauge accurately – there are so many variables – but, as a guide, Mr Furber suggests a four-passageway system such as his would cost about £50,000, including the separators.