Water and granite worktops: what’s the link?
Our old CNC head, cooled by plenty of water. (We can’t get near the new machine to photograph it!)
Water is the forgotten element which keeps industry working. In the UK about 75% of our captured water goes into industry, with just under 3% into agriculture and about 22% for domestic use – a large proportion of which goes straight down the toilet.
At Affordable Granite, water is vital for almost all the cutting and polishing work we do. Water cools and lubricates the blades as they cut, water keeps dust out of the air, water makes polishing processes more effective.
When everything is running – two saws, two CNCs, one edge polisher, guys working the hand polishers – we have a throughput of nearly 500l of water every minute. That is 30 tons an hour!
Hand polishing of white quartz, showing the spray coming off the diamond wheel.
Every process involving cutting granite or quartz for worktops creates dust, from bigger sandy grains through to the finest, clay-like particles. Every week we fit at least 20 homes with granite worktops. We keep growing, and that growth means more water, more dust particles, more material to be treated to avoid causing damage to our local environment. For a worktop fabricator our size, treating our own water is an economic necessity, of course, but far more than that, we want to do the right thing for the community and beautiful landscape where we are privileged to work.
A milling blade reducing the thickness of a slab for splashback use
One of our bridge saws making short work of Steel Grey Granite: water is essential!
Waterwall
Dust gets in the air too – and that is dangerous. Silica dust from cutting and polishing granite worktops can cause long term lung damage. Workshop staff wear masks, but filtering the air is also an important commitment for their safety. Our waterwall draws air through a hanging curtain of water, massively reducing the dust load. The output? Once again, water, with dust in it, that needs to be filtered and recycled.
There is another issue too. We recycle all our water – it goes round and round the system. If we didn’t clean it well at each cycle, the abrasive granite particles would destroy our (very expensive) machinery extremely fast. This is about the environment, but it is also about making good use of our investment and keeping the machinery for your kitchen worktops in good working order.
The grey sludge that can settle in untreated water
Over recent years we have upgraded our water filtration system more than once. Last year saw the biggest change yet, with big scale new kit. The treatment is multistage. Water comes off our machinery into tanks. It is then pumped into a settling tank which concentrates the particles of granite and quartz. Finally, this sludgy material passes into a compression filter which squeezes the water out. What is left is a semi-dry, clay like concentration of dust particles which is actually useful again. Skips of the stuff are taken away by our recycling provider.
Our biggest water filtration system yet arriving last year
The sedimentation tower being lowered into posuition
Installation: the tower positioned between the saw and polishing buildings
The tower is actually a massive settling tank. Water is pumped up into it from an initial holding tank, under the parking area in front of the factory. Flocculants are added, encouraging the dust particles to fall out of suspension and into the bottom of the settling tank. The water at the top of the tank is clean enough to be taken off and passes to our largest holding tank before being recycled back through into the water feed for the machinery.
Self-cleaning water filter.
Because the main settling tank relies on gravity and flocculation to clear the water, lighter debris like plastic is not removed. Bottle tops and bits of template may seen innocuous, but they can do significant damage if they find their way into any of our machinery. The self-cleaning water filter uses the water flow to power a rotor which pushes solid, clogging materials away from its filter holes. This allows us to screen out lumps of plastic and other bits and bobs without risk of getting a clogged filter.
The arrival of the compression system.
The thick sludge that settles at the bottom of the settling tower passes into fabric sleeves, held closed at the bottom by metal clamps. A hydraulic ram then squeezes the water out. The clamps open, the machine shakes the sleeves, and compacted slabs of semi-dry granite and quartz dust drop straight into a waiting skip.
Caked granite and quartz dust as it comes from the final compression process
As we all know, manufacturing industries can have a hideous impact on the environment, as can transporting product. By trying to keep our installations local, running efficient vans, and filtering our water, we try to keep our own impact to the minimum. We remain committed to further investment so that Affordable Granite remains one of the most environmentally friendly suppliers of Dekton, quartz and granite worktops. For our stock range of stone for granite worktops, see here, and for quartz worktops, here.
Stunning Cambria Brittanicca island in a barn conversion, Hampshire
