Sustainability: One simple step can drastically cut industrial water usage

25th April 2024

Sustainability: One simple step can drastically cut industrial water usage

Spray nozzles supplier Monitor Engineering, the sole agent for Spraying Systems Co US, the world’s largest supplier of spray nozzles and spray systems, offers a free sustainability audit that helps companies to plug water-wasting practices with their spray nozzles, tank cleaning nozzles and spray guns that have made manufacturers and food producers the country's biggest consumers — and in many cases, abusers — of scarce freshwater resources.

In the food and beverage processing industry, water is the secret ingredient. Between cleaning, heat transfer, sanitation and processing applications, it is estimated that the food industry uses about 1 ℓ of water to produce just one calorie of food that is consumed.

If that is multiplied, a 500 calorie lunch would use about 500 ℓ of water before it is prepared.

Breaking down these water consumption estimates across the rest of the industrial sector, the manufacturing industry seems to be using a disproportionately large share of the country’s freshwater resource. 

According to a whitepaper published by Spraying Systems Co., manufacturers in the US use about 45% of the country's fresh water, while only 18% is consumed by domestic users.

In the manufacturing and processing industries where costs and conservation are paramount, the high volumes consumed should be regarded as anomalies. 

For example, there is a mindset in the food processing industry that, when in doubt, use more water. If there is doubt about whether the water is clean, if there is doubt about whether it is sanitised, in many cases, the solution is to just use more water. It is a commodity, after all.

Water costs are rising but this is only part of the overall cost of consumption. In addition to the cost of the water itself, chemical usage also needs to be factored in, as well as the energy used to heat it, and the treatment and disposal of the water. Add all these costs up, and they become substantial.

Monitor Engineering is on the frontline, assisting customers to reign in these costs and simultaneously reduce industrial water consumption.

We do this through a service provided by Monitor that sends local sales engineers into plants around the country for a free top-to-bottom water usage assessment. The engineers look at worn or plugged spray nozzles, use the correct tank cleaning nozzles to reduce water and chemical consumption as well as cleaning times, and offer spray guns to block off open hoses.

During these assessments we uncover a wide range of issues and mindsets regarding water usage, working with sophisticated plants that provide years of water bills and usage records and others that cannot even locate their water meter. 

But what surprises us the most in this experience, are the simplest things plants have not done to shore up their water flow.

One of the things we frequently find in food plants is the unnecessary number of open hoses. One will see just a ball valve on the end of a hose functioning as a spray gun, and it is left wide open.

These open-hose systems can flow in excess of 75 ℓ/m out of every hose — often more than twice the amount that is required.

To illustrate the volume of waste that this produces, a study published in the previously mentioned white paper describes how a turkey processing plant in the US participated in Spraying Systems Co.'s water assessment programme. Before the assessment, the plant was using 15 open-end sanitation hoses spraying eight hours a day, five days a week, 50 weeks a year. That adds up to an annual water consumption of around 473-million litres. 

To cut water usage, Spraying Systems Co. introduced its CU150 GunJet spray gun to the plant — an ergonomic, lightweight gun that provides spray capacities with the feel that operators like and expect. The fix in this example was fairly simple as a spray gun was attached to the end of the hoses to cut the flow. With no more than a dozen or so spray guns, the plant brought its daily water consumption down by over 64 000 ℓ/d. This resulted in a yearly saving of over 15-million litres of water, plus all of the additional heating, chemical and disposal costs. Altogether, that translated to a yearly savings of over $30 000, which is a salary's worth of saving for the cost of 15 spray guns.