03 bwc business - blackwell water consultancy business issue 3.pdf · these are questions many...

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PO Box 235Darlington

County Durham DL1 9GN

www.blackwellwaterconsultancy.co.uk

Blackwell Water Consultancy Ltd News

• BWC short-listed for Scottish consultancy contractBlackwell Water Consultancy Ltd has recently been short-listed for a consultancy contract for

a client in Scotland. We hope to have more news about this before Christmas.

• Procee modelling partnershipWe're returning to one of our old skills and moving back into the area of process modelling.

Over the last few months we've been working with a software supplier on projects to develop

process modelling solutions for the UK water industry. More news in the New Year!

BWC Business

In the next issue

Next year we will launch our

Day in the life of....series. Our

first three issues have

concentrated on general topics

and issues for business and

domestic consumers of water.

In issue four we look in detail

at how our drinking-quality

water is produced, from initial

rainfall through treatment to

delivery through your taps.

Merry Christmas from BWC!

It's been a hectic but productive

year for us here at BWC and

we're hankering now for mince

pies and our feet up by the fire

as we gaze fondly at an idyllic

snowy scene outside. In reality

we'll be doing our last minute

shopping with everyone else.

Merry Christmas to all and we

wish you the best of New Years!

Who we are

Blackwell Water Consultancy

Ltd is based in north-east

England but operates

throughout the UK. We give

advice to businesses in all parts

of the UK economy about the

efficient and sustainable use of

water.

This covers everything from

assessing domestic fixtures and

fittings to designing entire

treatment plant. Our website

has more information about

what we do.

Water, water everywhere...................The UN Copenhagen Climate Change

Conference 2009 is due to end on December

18th. It will address, or try to, the key issues

facing the world as we cope with a changing

environment. All bar one. As we write this we

understand that the Copenhagen conference

does not intend to include water sustainability

in any of the agreements the conference will

produce.

Why? Water is still seen by consumers in the West as a

cheap, bulk commodity. In the UK we have high quality

water delivered to our door at all times for a reasonable

price. The environmental aspects of producing water

(the elelctricity consumption, the need to use certain

chemicals) are hidden from most consumers and we

don't have to walk miles each day to get it.

But will this always be the case? As the planet's climate

changes will water always be available as it is now,

especially in the West and for us in the UK. The

Copenhagen conference will rightly address the role of

carbon dioxide emissions, and it will be bogged down in

the row over the alleged cover-up or distortion of certain

aspects of climate change.

This issue was brought home to BWC at a recent event

we attended. A local businessman told us that his

teenage son leaves the tap running full when cleaning

his teeth. A classic example of water inefficiency said the

businessman, but how does it really impact climate

change? His son was of the opinion that we live in a

rainy country with a plentiful supply of water and that

letting clean drinking water run down the drain was,

therefore, wholly acceptable.

Producing drinking water can be an energy-intensive

business when done on a large scale. If only one

person in the entire UK leaves the tap running then the

effect is, in truth, negligible. But it's not just one person,

and leaving the tap running is only one way that water is

wasted. Consequently an enormous amount of energy is

wasted each year with clean water that goes down the

drain. Wasted energy eqautes to carbon dioxide

emissions that may have been avoided.

And that brings us to the topic of this edition of our

newsletter – water efficiency and, in particular, re-using

and recycling water. We'll take a brief look at how we

can get greater use from our water.

In this issueWater, water everywhere P.1

Industrial wastewater P.2

Re-using & recycling wastewater P.3

BWC news P.4

I S S U E

D e c e m b e r2 0 0 9

03

BWC Business Issue 4

4 1

Industrial wastewater: some facts and figures

The web-site of the Office for

National Statistics (ONS) shows

that industry, manufacturing and

the service sector in the UK

uses 80% of all water

abstracted. This is around 10

billion cubic metres per year.

This is a truly enormous figure

and shows how reliant industry

is on the continuous provision or

availability of clean water. But,

does the water really need to be

drinking water quality?

The answer is a firm “no”. Much of the

water inudustry uses is for duties such

as heating, cooling and washing. In

many cases, once the water has done

its job, it ends up down the drain.

Think about this from the point of view

of sustainability, though. If you're a

factory manager, do you really need to

use as much water in the first place?

Can any of your wastewater be re-

used without treatment? Could some

form of treatment give you re-usable

water? These are questions many

companies actively pursue as the use

of water becomes another cost to be

reduced.

Industry uses gigantic quantities of water, much of it drinking quality. How much does it really use? Re-using and recycling industrial wastewater

Turning effluent into high-purity water

High-purity water is often needed

for use in boilers. In simple terms,

the better quality the water, the

less scale occurs in the boiler. It

is possible to turn effluent into

high-purity water but the costs

can be high.

High-purity water is best

produced by membrane

processes. These use cylindrical

membranes formed from material

with very fine pores. The

membranes can remove

incredibly small material (down to

the molecular size) but clearly

solid material will cause them to

clog. Consequently, pre-

treatment with a solids-removal

process is advisable. This type of

arrangement can produce very

high-purity water but even that

may not be good enough for

some industrial users.

Ultra high-purity waterThis can be produced by using

what are known as ion-exchange

processes after membrane

treatment. These are simple and

consist of a vessel filled with very

small beads. The beads are

designed to attract certain

molecules in water and can so

mop up anything that gets past a

membrane process. Io-exchange

processes also have low power

requirements.

How, then, can industrial consumers,

large and small, reduce water

consumption? The first stage is to

carry out a full water audit. This is a

service BWC offer and it entails a

thorough review of everywhere water

is used at a manufacturing site. Once

you know how much water you use,

realistic targets for reducing

consumption can then be set.

sending you your water bill.

On large sites, with a number of

different operations, it is often the case

that individual parts of the process are

not metered. Sub-metering entails

installing flow meters at the entry point

to individual parts of a large plant,

factory or even office building. This

enables water use in each part of the

site to be measured.

Measurable goals

A water audit often

shows up “quick wins”

that can reduce

consumption at no

cost other than

changing practices.

Examples include turning off taps and

hoses when not in use or sweeping

debris rather than rinsing it down the

drain (this can reduce trade effluent

costs as well since solid waste can

increase the strength of effluent).

To truly get to grips with reducing water

consumption, though, you should

consider sub-metering. All businesses

should have a water meter that records

consumption on the entire site. It's this

meter the water company uses when

Simple tips

Reducing water use

doesn't have to be

complicated or

expensive. Quite

often big savings can

result from relatively

small actions.

The UK government's Enhanced

Capital Allowance (ECA) scheme

provides tax incentives for installing

water-efficient equipment. As well as

industrial water treatment processes it

also covers items such as taps,

showers and toilet facilities. The tax-

break can make the financial aspect of

reducing water use more attractive. In

short, reducing water consumption for

businesses can be simple, low-cost

and financially worthwhile.

“UK industry uses

around 10 billion

cubic metres of

water each year”

It's clear that using less water can

reduce operating costs substantially

but how can you tackle re-use and

recycling? And what is the difference?

At BWC we use the terms re-use and

recycling to mean two different things,

although we recognise that some

people use them to refer to the same

process.

We use re-use to men using water for

more than one purpose without treating

it in any way. For example, spent

cooling water may well be clean enough

to wash items of equipment or cleaning

vehicles.

We use recycling, however, to refer to

instances where wastewater is treated

before it is re-used. On page 2 we

noted how a food processor recycles

treated effluent back to their factory.

The wastewater has passed through a

treatment process before being

pumped back to the plant. Treatment is

sometimes needed to remove

impurities that prevent the wastewatre

being re-used directly.

The type pf treatment needed depends

on the reason why you want to recycle

water.

If your water is needed for food

applications or as high-purity boiler

water then some form of membrane or

ion exchange process may be needed.

A solids-removal process may well be

required too. On the other hand, if all

you want to do is use water for

washing, a simple settlement process

may be all that's needed for removing

solid material. In a former role, BWC

helped to commission an oil-water

separator for a metal processing

company. This allowed oily water to be

treated, recycled and oil recovered.

Trade effluent costs also decreased

signifcantly with this one!

Q&A – what sort membrane treatment processes are there?

Q: Who supplies membrane equipment?

A: There are a number of suppliers of membrane

modules, although often other contractors may build the

rest of the plant. Dow, Koch, Toray and Hydranautics are

the main supplies of membrane modules.

Try:

http://www.dow.com/liquidseps/prod/prd_film.htm

http://www.kochmembrane.com/

http://www.toray-membrane.com/application/page.aspx

http://www.membranes.com/ (Hydranautics home page)

Q: Any design information out there?

A: Tons of it. The membrane suppliers we mentioned in

the first answer all supply software, free of charge, that

can be used to develop outline designs for membrane

plants.

Dow produce an excellent and easy to understand guide

about things to look for when considering installing

membrane plant. Go to:

http://www.dow.com/liquidseps/service/lm_techinfo.htm

2 3

Show me the money!

OK, we hear a lot about how

reducing water use can save

businesses money. Just exactly

how much money are we talking

about and can I have some

please?

Let's use the statistic on the main

page, i.e. Industry uses around 10

billion cubic metres of water each

year. The average cost of one

cubic metre of water is around

£1.05. On average then, the total

cost of the water used by industry

is £10.5 billion. Saving 1% of that

each year comes to £105 million.

In truth, it's possible for many

businesses to reduce their water

consumption by much more than

1%. And remember, reducing the

amount of water that goes in to

your premises should reduce the

amount of effluent you discharge.

As we've seen in previous issues,

this can also give lower trade

effluent costs through careful

management.

Re-using and recycling water can

lead to much greater savings,

although the investment needed to

do this is clearly higher. For

example, the magazine Process

Engineering recently reported on a

food processing company that now

recycles 55% of its effluent back to

the main factory, saving almost

£700 each day in water costs

alone. Over one year this saves

almost £250,000 in water costs.