From a young age we’re taught the fact that the Earth is made up mostly of water. Seventy-one percent to be exact. It seems as if water is a truly abundant resource. But the fact that many of us don’t readily know, is that only 1% of that total is fresh water, suitable for consumption.
While an average American household can use around 350-400 gallons of water per day, the majority of the Earth’s freshwater is used in agriculture and manufacturing. It’s evident in these quick facts:
- It takes 2,900 gallons of water to make one pair of jeans
- It takes 1,300 gallons of water to produce a 12 oz steak
Industrial freshwater consumption leaves us with wastewater, which is the discharged used water that comes from residential, commercial, agricultural and industrial use. Through wastewater management, we can ensure sustainable wastewater treatment, water reuse or water disposal to protect our freshwater supply.
We interviewed our own ERC Project Manager, Kermit Burkholder, to help us outline the process of sustainable wastewater treatment and reuse.
What is included in the process of wastewater segregation?
We now have several options for treatment so the first thing that happens when a truck arrives is for a sample to be collected and submitted to our lab for testing. This will tell us if we can process it and which system will do the processing.
Can wastewater ever be reused right in-house or does it always need to be removed for treatment?
Some of the waste streams that we process could be treated for reuse in-house, but the companies would need to look at the economic impact first. Some of the things that would need to be considered are: how clean they would need to get the water for reuse, the capital expense to set up a system, the cost and headaches of operating the system, and the cost to remove the bi-product of the system. At this point, most small to mid-size companies do not want to take the responsibility to do this.
What type of wastewater is eligible/not eligible for treatment?
Of course the waste needs to be to be non-hazardous. But from there it’s hard come up with a definitive answer. There are just so many different companies, using so many different chemical compounds, in so many different concentrations, that we can’t come up with a list of “this will or will not treat.”
There are certain classes of chemicals we do know to look out for. Waste streams containing alcohols, glycols, or cleaning compounds are more difficult to treat, but the concentrations of these compounds play a big part in treatability. We typically look at any new stream on a case- by-case basis. We prefer that the company provide a sample of the waste stream that we can do bench testing on to determine treatability.
What steps are involved in the treatment process?
If the waste stream will treat in our standard treatment system, the water is co-mingled with other similar streams in settling tanks to allow any free oil to raise to the top. The water from these tanks is then transferred to the main waste water treatment system feed tanks. This water is then treated in a chemical treat process using dissolved air floatation to separate the contaminate from the water.
If the stream is a mixture of oil and water that will not separate on its own it is pre-treated in a process to break the emulsion. The water collected from this process is then transferred back to the first treatment step.
We are seeing an increasing number of waste streams that will not treat in our first or second stage systems so we are in the process of setting up a third system where we treat an individual stream. In this process we can tailor a special chemical formula needed for treatment. The contaminates separated in this process are removed with plate and frame filter presses.
How is water “reintroduced” to be reused in the environment?
All of the water that we process is treated to the point that it is acceptable for discharge to the local biological sewer system. From there it is returned to the local fresh water system.
Are there differences in how you handle wastewater by industry?
Waste water from industrial and manufacturing sources needs to be handled differently because of the types of contaminates in the water. These streams often contain hydrocarbon based compounds and heavy metals. Both of these types of contaminates will upset the biological systems that are used to treat municipal and agricultural waste waters and need to be removed by a chemical process first. The chemical treatment systems are more challenging to operate so there are far fewer of these systems in existence. This is the area that ERC specializes in.
Any other tips for sustainable use of water in industry settings?
The supply of good, clean, fresh water is something that has been taken for granted for a long time but is now becoming a major concern worldwide. If our current practices do not change I foresee a time when fresh water will become a regulated commodity. At some point, industries will be forced to find ways to reduce or reuse their water resources. For industries that wait until that time, the demand for equipment and expertise will be so high that the economic impact will be much greater. If a company would like to get a head start on the process but does not know where to start or is afraid to try, we would be glad to offer our technical support.