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The Problem

The CCI operates a state prison in Tehachapi. The prison’s wastewater treatment plant was undersized for the prison and needed an upgrade. In the winter of 2008, the state put out an RFP to construction contractors. Part of the job would be to remove the wastewater sludge out of the prison’s lagoons prior to decommissioning. As with most construction jobs, time was of the essence and a reliable subcontractor would be needed to remove the wastewater sludge in a timely and professional manner.

The P&H Senesac Solution

Eventually, the CCI awarded the job to Cushman Contracting Corporation (CCC). We worked extensively with CCC to formulate a plan of action that would get construction underway as quickly as possible. We settled on a plan to pump two of the smaller lagoons into one of the larger lagoons. This strategy allowed them to begin their work sooner.

By mid-summer 2008, we moved our Maximus System into the prison and began dewatering the condensed lagoon on site. Since the dewatered biosolids were slated for compost, we brought in a trash scalper and degritting machine to remove as much of the inorganic waste as possible. During the course of the summer, fuel prices skyrockedted to $5.00/gallon, placing a high priority on getting the solids as dry as possible. We successfully dewatered the biosolids 5% higher than expectations, resulting in considerable cost savings.

We finished the first phase of the lagoon clean-out by October 2008 and caused no delays in the construction of the plant. In January 2009, the CCI contacted P&H Senesac to do surveys and sludge estimates for the second phase lagoons. The second phase was started at the end of December, 2009 and completed at the beginning of February,  2010.  In this six week span, P&H Senesac cleaned a staggering 484 dry tons of solids out of the lagoon.

The Problem

WM’s Grand Central Landfill operates a Lechate Treatment Plant. They began by dewatering with a plate and frame press. However, their dewatering press proved unable to remove any of the carbon-laden fine solids in the lechate sludge waste. Out of desperation, they began pumping this sludge to their lagoon and holding tanks. Eventually, they began to run out of places to put this sludge and needed a fast, effective way to remove this material from their process.

The P&H Senesac Solution

In november 2007, WM contacted us about renting one of our machines for 30 days to remove some of the solids from the lechate waste. We went them our Spartan System and provided them with two weeks of training for their operators. They were stunned by how easily and effectively they could dewater with our Spartan System. In fact, they kept the machine an extra 15 days (through the Christmas and New Year’s holiday) in order to remove as much accumulated solids from their process as possible.

However, there remained more unfinished work to their process. They pumped much of the previously mentioned waste to a tank and lagoon. Unfortunately, they could not access the location where they had set up our Spartan System due to the cold temperatures. In May 2008, they hired us to return in order to clean out their lagoon as well as another lechate holding tank. For this project, we used a cutting-edge, prototype centrifuge which we configured to work with our proven Spartan System. We removed 100 dry tons of solids from their process, putting a marginal amount of solids back to their plant.

WM’s personnel was so impressed by the performance of the centrifuge in processing their waste solids that they eventually replaced.  However, they still needed a contractor with the expertise on moving solids out of their holding structures. So, in June, 2013, they contracted P&H to come in and remove the sludge from one of their leachate holding tanks.  Coordinating with the plant personnel, P&H pumped the leachate waste solids to the holding tank feeding WM’s centrifuge.

The Problem

Exeter township was scheduled to upgrade their antiquated, press-based dewatering technology to a modern, high speed horizontal centrifuge in 2008 as part of their wastewater plant upgrade.  After successfully using an Alfa Laval-equipped P&H Senesac dewatering system for a pilot test, they proceeded forward with construction in 2010.  However, they would need a temporary dewatering solution during the upgrade.

The P&H Solution

P&H was able to supply a Spartan temporary dewatering unit In June, 2010.  P&H personnel set up and operated the centrifuge for a week in order to effectively demonstrate that the system could handle the flow rate from the digesters.  After stabilizing and optimizing the process, P&H proceeded with training the plant’s personnel on basic centrifuge operations, process optimization, and troubleshooting procedures.  We provided customized operating documentation including basic start-up and shut down procedures, troubleshooting sheets, and optimization guidelines.  After they took over the operation for the next three months, P&H provided technical and on-call customer support, even responding to calls on Sunday nights.

Four years later, Exeter awarded P&H Senesac a contract to clean out both of their digesters.  From October 22-December 5, P&H successfully dewatered 135 dry tons of biosolids out of two digesters that had not been cleaned out in 15 years.

The Problem

The Village of Essex Junction’s waste water treatment plant features two-1 million gallon holding tanks to store anaerobically digested secondary sludge from their digesters.  From 1998-2013, the economics  sided with on-site dewatering to deal with the biosolids build-up in the facilty as opposed to hauling off-site.  However, finding a reliable dewatering contractor proved challenging.  They struggled with contractors polluting the plant with solids they were supposed to be removing, couldn’t deliver dry cake solids, couldn’t arrive on-site in a timely manner, and others who couldn’t operate in all weather conditions.

The P&H solution

In November, 2004, P&H was awarded a bid to dewater approximately 500,000 gallons of 5-5.5% solids.  The results were stunning.  Despite working through cold, performance-inhibiting temperatures of December in Vermont, we were able to process 470,000 gallons of 5.5-6% sludge to 24-26% cake solids.  The costs savings in disposal as a result of the dryer cake solids savings meant that the Village was able to spend more money on dewatering.  Choosing to soul source P&H after this successful dewatering project, the Village was able to fully empty their sludge holding tanks for the first time in decades.

We did this, in part, by suggesting that the dewatering be moved into the spring-summer months to maximize the dryness coming out of the centrifuge.  This yielded an increase in of the average cake solids up into the 27% vicinity.   We began using our Maximus dewatering system at a lower than maximum output.  With these performance enhancements, the Village level-funded their solids handling budget, lowered their disposal costs, leaped far ahead of their biosolids accumulations.

The hands-on, custom-tailored approach to dewatering solutions made P&H the logical choice for the Village’s digester cleanout work as well.  In 2008, they had us clean out both their primary and secondary digesters.  Despite not being cleaned in over 20 years and being overloaded with inorganics and grease, P&H cleaned two-500,000 gallon digesters, scalped all of the inorganics and grease out, transferred the sludge to the Village’s holding tanks, and processed digester contents and the Village’s usual waste stream into the holding tanks.   The whole process went so well that the Village had P&H do the next round of digester cleaning in 2013 as part of their waste water plant upgrade.

In the winter of 2008, Tate and Lyle’s Starch processing facility in Houlton, Maine experienced a failure in their reed beds used for solids management in their waste treatment.  As a result, the plant ended up stockpiling 200,000 gallons of 14,000 mg/L of TSS waste water when they contacted us Mid-February.  After securing the proper polymers necessary to dewater their waste stream, we mobilized our Spartan dewatering system two weeks after the initial contact.  Our rapid response crew successfully dewatered 335,000 gallons of miscellaneous waste sludge that had accumulated in their process in addition to their daily flows, preventing a costly shut down of their facility in two weeks’ time.