Various occasions call for temporary water and wastewater treatment capacity. Maybe part of the plant is down for maintenance. Maybe a storm event affects operations. Maybe a plant upgrade is underway and a fill-in is needed during the transition to the new system.

For whatever reason, it helps to have capacity that can be moved in and connected quickly. That’s the idea behind rental treatment solutions supplied by WesTech Engineering. The company offers mobile, containerized, skid-mounted systems that can be on site and operating within days with little upfront cost.

Temporary solutions encompass a wide variety of treatment processes and include tanks, accessory equipment and a range of support services. Tyler Gladwin, application engineer for the rental services group of WesTech, talked about the offering in an interview with Treatment Plant Operator.

What is the market rationale behind this offering?

Gladwin: Rental is a great way to provide a service that all of our clients need at some time. That includes clients who use WesTech capital equipment and need temporary solutions, such as while they’re waiting for new equipment to arrive. 

What are some of the most common situations that call for rentals?

Gladwin: A large need is when they have shutdowns for different processes within the plant that need to be inspected after being in service for 10 or 20 years. While they are looking at the internals, they still need that water or wastewater to be treated. Other cases include repairs or retrofits to existing infrastructure, as well as emergencies, which can come up at any time. 

Are these units designed and built specifically for the rental market?

Gladwin: Yes. They are designed so users can install them and take them down quickly. Many of the units are built in frac tanks or shipping containers that can be mounted on trailers or delivered on a carbon steel or stainless steel skid.

Which processes are rented the most often?

Gladwin: Some of the most common ones we see are multimedia pressure filters, our RapiSand ballasted flocculation units, dissolved air flotation systems, disc filters, aeration units and containerized membrane ultrafiltration systems.

In what capacities are these units available?

Gladwin: Pressure filters and RapiSand units can handle up to 1 mgd. The ultrafiltration systems can process about 1.5 mgd. Aeration unit capacities vary based on the strength of the wastewater; six of them in series can treat 0.3 mgd on average. The disc filters can treat 1 to 2 mgd, and the DAFs can treat about 0.75 mgd.

Can multiple units be installed for larger flows?

Gladwin: Yes. We usually place them in parallel, except for aeration units, which are typically run in series. For example, a customer who wanted 2 mgd capacity in a RapiSand system would rent two units. The different systems are very modular; they can be placed in parallel to deliver the flow the customer needs.

How easy is it to connect these units on site?

Gladwin: Connection is very simple. For example, the pressure filter units are designed so the user can put the influent or the effluent on either side. The systems are designed to use simple clamp fittings for connections, and they have just one power input.

How long does it take from the time a unit arrives on site until it is operating?

Gladwin: Typically about one week, although that depends on how fast >span class="s5">site as soon as the equipment arrives, they could have it running the same day.

Are there any challenges in making space for the units on plant sites?

Gladwin: The packages in general are very compact. If customers can fit a shipping container somewhere on the site, they can fit one of these units there. A gravel pad is usually a sufficient foundation for the equipment.

What services typically go along with the rental packages?

Gladwin: Generally, we will send someone to the site to show team members how to run the equipment, what the operating parameters are and what adjustments they need to make. We can do installation as well.

What if a user has trouble with the system after the training representative leaves?

Gladwin: They usually have telephone support available at any time of day. We can also send our own operators or process engineers to the site to help them with upsets and give them more training. On top of that, we can have our own technicians do the entire project on a turnkey basis. We often do that for industrial customers.

What is done to ensure the end product is compliant with regulations?

Gladwin: We can take charge of the permitting. If the state requires the user to meet certain limits, we can take that into our scope so that we’re responsible if the water doesn’t meet the required quality. We can also offer performance guarantees. For example, if a drinking water plant needs to meet a limit of less than 5 micrograms per liter of arsenic, we can guarantee that our process will hit that.

Can you describe a case where rental equipment helped a user solve a problem?

Gladwin: At a resort community in Arizona, a contractor needed one to two months to replace the media in one of our Trident package water treatment plants. Within a week, we were able to send a RapiSand unit and a pressure filter to the site, and we were able to start treating water almost immediately.

Is there an example you can cite on the wastewater side?

Gladwin: We provided temporary aeration for a lagoon system in Kentucky. The lagoon liner was collapsing; they needed to drain and dredge the lagoon, remove the liner, compact the soil, add the new liner, add the sludge back and get the lagoon running — a process that took about six months. We provided six frac tank aeration units in series to treat about 0.33 mgd. All we had to do was seed them with return activated sludge from a local municipality. They were online and meeting specifications within one week.

What should customers look for when evaluating rental equipment suppliers?

Gladwin: They need someone who can show up and be ready to run water through the unit as soon as possible. Our media filters come with media installed. The ultrafiltration systems have an integral booster pump and backwash tank, as well as a clean-in-place pump so chemical cleanings can be done on site. It’s important to have equipment that’s all in one piece. They also want a solution that’s specific to their need, and they want to work with a company experienced with multiple industries and types of water or wastewater.