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Roughly half the states in the U.S. are currently experiencing a form of drought, ranging in intensity from abnormally dry to exceptional drought, according to the U.S. Drought Monitor. When drought conditions become severe, which is the case for the plains and western states, local government responds with mandates to conserve water. For example, in Wichita Falls, Texas, the entire city's water supply is now being recycled and reused. In California and Washington, residents and industrial facilities alike are under a statewide mandate to conserve water, and governors are calling for permanent behavior changes from residents.

Response to drought situations is one of the top 3 reasons why manufacturers recycle and reuse their industrial wastewater. Manufacturing facilities require large volumes of water to make their products, and they purchase that water from the city. When there isn't enough water to go around, these facilities face higher water costs. Most significantly, however, they face production losses and downtime when they don't have access to the water they need.

In the midst of a drought, requirements may be handed down to manufacturers for implementing a reuse solution or reducing their consumption by a certain percentage. This requirement may be from their corporate offices in order to mitigate losses if the situation persists, or it may come directly from the governor. Either way, the midst of a drought is not too late for implementing a wastewater recycling system. The startup of the system, however, could be delayed significantly if there isn't a sufficient amount of water available for the initial startup. This has been the case at facilities in drought areas such as Texas, where the manufacturer waits months before they have access to the volume of water they need to operate their wastewater treatment equipment.

California Drought

In areas like California, Texas, and more recently Washington state, the motivations for a long-term conservation and reuse process is high because they are currently experiencing the pain that a lack of water causes. the best time to implement a wastewater recycling system, however, is before drought conditions become severe. While the motivations at that time are less urgent, manufacturers are recognizing that the investment now will mitigate the risks later. Manufacturing facilities in states near the most severely dry states are already heeding the warning and taking action now in case the drought situation elevates in their area.

The long-term drought conditions that we're seeing are not limited to reservoirs that feed water directly into cities. The more severe problem is the depletion of groundwater that is pumped out to make up for the lack of water in the reservoir. Manufacturers recognize this as a risk factor for future production. The only way to guarantee they have the water they need is to recycle the water they do have access to. Industrial water recycling systems offer peace of mind and drastically reduce the volume of water that is consumed by a facility (this also saves money). Instead of consuming 100s of thousands of gallons of water daily, they may take in 100s of gallons weekly or even less frequently than that (to replace the concentrated water that can no longer be reused). Some facilities are even recycling their gray water and reusing it back into their manufacturing process. An Alcoa facility in Texas, for example, is installing a natural (NEWT) system that will remove biological contaminants from their gray water and then feed that treated water to their industrial water reuse system, which feeds water back into their manufacturing process. The water issue isn't a new one, and it is only becoming worse. The manufacturers who respond now will not only alleviate stress for themselves but also alleviate stress on the water resources in their area.

ProChem strives to help their customers establish the highest level of credibility and a positive reputation within the regulatory community. Their goal is to significantly reduce the amount of fresh water that manufacturers require by providing sustainable solutions that will also benefit the customer’s bottom line.

What are Ion-Exchange resins?

Ion-exchange resins are small, porous beads that are negatively or positively charged, allowing them to grab onto ions (contaminants in the water) that are attracted to that charge. These resins are solvents (insoluble in water), and they range in diameter from 0.3 to 1.5 mm. Resin is placed in a vessel, usually called a column, and submerged in water where it forms a layer on the bottom called a bed. The bed absorbs water and swells when it is first immersed. Immersion conditions the resin. When the resin is fully conditioned, the beads contain 50 - 70% water.

Wastewater is passed through the resin columns while the resin bed is gently agitated. The agitation allows the water to flow uniformly around the resin beads. The agitation actually increases the amount of surface area that comes in contact with a wastewater, which increases the likelihood that the porous openings will come into contact with ions. Imagine the resin bead as a ball covered in holes. As the ball rolls and bounces in the wastewater, its holes become exposed to the particles suspended in the water. Due to the charge, if the ions come into contact with the resin, they will be attracted to it and become trapped in the pores.

There are two main types of resins: Cationic and Anionic. Cationic (pronounced like "kat-eye-on") resins are negatively charged and remove positively charged cations. Here are some examples of ions that can be removed by Cationic resins: Chrome (Cr), Nickel (Ni), Zinc (Zn), Copper (Cu), Lead (Pb), Calcium (Ca), and Ammonia (NH3).

Anionic resins are positively charged and remove negatively charged anions. Here are some examples of ions that can be removed by Anionic resins: Chlorides (Cl), Sulfates (SO4), Nitrates (NO3), Carbonates (CO3), Phosphate (PO3), Bromide (Br), and Hydroxide (OH).

Why use Ion-Exchange resins for wastewater treatment?

Ion-exchange resins fill a unique niche when it comes to wastewater treatment. They are ideal for treating waste streams that are lower in total suspended solids (TSS) and in contaminant levels than those treated with a chemical program. Other advantages include:

  • No sludge generated. If the wastewater being treated is from an electroplating operation, for example, sludge is considered F006 hazardous and can be very expensive to haul off.
  • Less labor intensive than chemical treatment.
  • Columns ship easily and are usually considered non-hazardous.
  • Much smaller space requirements than a chemical treatment system. A system that treats 10 gpm - 20 gpm can easily fit in approximately a 4 x 10 footprint.
  • Lower overall operation cost.

There are several suppliers that offer ion-exchange resins and the columns. The simplest way to use ion-exchange is by utilizing a column exchange program, which is available through certain vendors. These programs allow you to exchange your exhausted columns for regenerated ones without impeding your wastewater treatment process or production. Contact an industrial water treatment company who can help you select the most effective resin, install the system, and set up a routine column exchange program that works for your facility.

ProChem strives to help their customers establish the highest level of credibility and a positive reputation within the regulatory community. Their goal is to significantly reduce the amount of fresh water that manufacturers require by providing sustainable solutions that will also benefit the customer’s bottom line.

What is Jar Testing?

Jar testing is a method for determining the treatment method that will be used when treating wastewater. Specifically, it helps to determine which chemicals will be needed and the proper dose rates for those chemicals. Jar testing is essentially a miniature batch treatment tank with all the variables under control of the operator. It usually consists of a "jar" or beaker of a known volume and a variable speed mixer.

The mixer can be as simple as a glass rod stirred by hand, a laboratory stir plate with a magnetic stir bar, or a motor driven metal impeller (similar to the mixers found in many wastewater treatment reaction tanks). It is also a good idea to have a pH meter for jar tests, as many of the reactions that occur during treatment require specific pH ranges.

Water Treatment Jar Test

How do you Jar Test?

As with any experimentation, it is good practice to take notes, keeping track of the additions and observations you make during the testing. A water sample should be taken from the equalization tank (a holdingtank where all wastewaters are intermingled before being pumped to the wastewater treatment system). You should sample a specific volume, usually a liter. Next, agitate the water in the jar, and measure the pH. In waters that may contain cleaner as well as dissolved metals, it is common to lower the pH to 2.5 - 3.0 with dilute sulfuric acid if it isn't already at the required pH.

Once the pH is lowered, you should being adding chemicals. Most often, coagulant is added at this stage. Coagulant is measured in parts per million (ppm), which is one milligram of something in one liter of water. In this case, one ppm is a one hundredth of a milliliter in one liter of water, with 1 milliliter in 1 liter of water equaling one thousand ppm. Coagulant addition may range from 1 to several thousand ppm depending on what is being treated. Allow the coagulant to mix in the water.

Next, the pH should be raised using dilute sodium hydroxide, usually to a range of 9.0 - 10.0. If required, because of complexors that might be present in the water tying up the metals, a metal precipitant can be added at a dose of 50 - 200 ppm. When metal precipitant is mixed well, the polymer should be added. In water being treated for metals, an anionic polymer is commonly used. Polymer addition should be made with good mixing to evenly distribute the polymer throughout the water. Mix for 30 to 60 seconds, then turn off the mixer. A heavy precipitate or floc should form and begin to settle to the bottom of the jar.

At this point, the jar test is complete, and a sample should be filtered and then taken to a treatability laboratory for analysis.

ProChem strives to help their customers establish the highest level of credibility and a positive reputation within the regulatory community. Their goal is to significantly reduce the amount of fresh water that manufacturers require by providing sustainable solutions that will also benefit the customer’s bottom line.

High Pressure Reverse Osmosis (I-PRO) - ProChem Reverse osmosis equipment has been used for many years to purify drinking water. It is used all over the world to desalinate seawater and bring fresh water to those with limited or no access to it. There are even household versions of reverse osmosis equipment to purify well water before it's fed into the ice maker, for example, More recently, this technology is being used in industrial facilities to recycle the wastewater from manufacturing processes.

Reverse osmosis equipment facilitates the natural osmosis process in reverse. Osmosis occurs when a less concentrated saline solution is drawn to the higher concentrated saline solution. For example, a flower's roots absorb water from the ground through osmosis. In reverse osmosis equipment, a semi-permeable membrane separates the higher concentrated water from the lower concentrated water. A little pressure is applied to the higher concentrated water, forcing it to flow through the membrane, where the salts and other particles become trapped. The result on the other side of the membrane is desalinated and filtered water.

The same reverse osmosis equipment has been scaled down for us in industrial facilities. Industrial reverse osmosis equipment uses a much higher pressure than desalination equipment, operating at 800 to 1,200 psi. Desalination equipment operates between 200 and 400 psi. Because of the higher pressure, the industrial reverse osmosis equipment can treat water with up to 35,000 ppm of total dissolved solids (TDS) while the desalination equipment treats water with TDS up to 1,500 ppm. This allows the industrial equipment to remove most any dissolved solid found in wastewater, such as heavy metals.

The effluent quality exceeds discharge permit limits and is ideal for reuse applications. It is being used to recycle industrial wastewater at a rate of 75% to 95%, instead of treating and discharging. The purify of the effluent can even be adjusted, depending upon what the manufacturing process requires. For example, electronics manufacturers require high purity water.

The disadvantage of industrial RO equipment is the rate at which membranes can become fouled. Replacing fouled membranes is expensive and requires the unit to be shut down. That's where preatreatment comes into play. With the right physical/chemical pretreatment process upstream, the life of the membranes inside the unit will be extended greatly. Cleaning membranes regularly can also extend their life.

Reverse osmosis is no longer just a treatment for drinking water. It enables manufacturers to conserve water in innovative ways by recycling their wastewater. For example, a manufacturer in Texas is using industrial reverse osmosis equipment to recycle both their industrial wastewater and the facility's sanitary water for reuse back into their manufacturing process.

There are hundreds of water treatment companies for manufacturers to choose from for their industrial water treatment needs. These companies advertise online, exhibit at trade shows, and send brochures to you. The first thing for you to understand is that not all of these companies are the same. They don't provide the same services and technologies, and they don't have the same philosophies. So, how do you determine which company is best for your facility's unique needs?

Decide What You Want

Rather than calling every water treatment company you find online to ask for a quote or a sales pitch, I recommend that you make a list of what it is you want from a company. I'm not talking about products, like deciding you want polymer or ion-exchange columns. That is only part of the list. Rather, you should decide as a package what attributes, qualifications, and peripheral services you want the water treatment company to offer.

Create your wish list, and don't limit yourself. It is possible to find one company who provides all the services you need. For example, do you need them to install the equipment? Do you already have a filter cloth supplier? Do you need consultation and engineering too? Many companies offer more than just equipment or chemicals. Some companies provide engineering services and will custom tailor solutions to each application. Some provide outsourcing services and operate your systems on a daily basis.

Location is something to consider: Many manufacturers maintain a successful relationship with their water treatment company from states away. Don't limit yourself by looking only locally.

Research, Research, Research

Online research is a great tool for finding out who a company really is and what they really offer. Now that you know what you are looking for, you can narrow down your call list to companies who offer at least most of what's on your wish list. Don't just look at their products listed in bold text, read their case studies, look at their networks on social media. This will help you understand the company's philosophy, credentials, and the type of people you will be interacting with.

Monitoring capabilities are something to consider: Gathering and reporting data performance data for wastewater treatment is becoming a key part of facility management for manufacturers. Some use that data to identify product defects earlier and prevent further production loss.

Contact Your Top Choices

Contact only the companies that meet all or most of your wish list requirements. Be ready to discuss the scope of your needs and answer questions about your goals, permits, and current treatment process.

Water analysis is something to consider: If the company you contact does not mention wanting to test your water, consider lowering that company on your list and looking elsewhere. Analyzing the water that needs to be treated is the only way for a water treatment company to offer any real solutions, quotations, or guidance to you.

Finding the right company now could mean that you are not searching for a new one later. Decide what your need for your facility, and then find out which water treatment company best meets your needs.