News from Schwing Bioset

Screw Press and Bioset Demo Leads to Treatment Plant Expansion

 

Written by Tom Welch, September 10, 2015

The Springfield, IL, Metro Sanitary District (SMSD) Sugar Creek Plant is going to be expanding over the next two years.  They currently have no dewatering capability and they treat their liquid sludge with lime and liquid land-apply on their own fields onsite at the plant.  In June of 2013, Schwing Bioset was invited to run a dual demo of their screw press and Bioset systems.  The pilot study was conducted for two weeks where the Waste Activated Sludge (WAS) was dewatered with the screw presses and then converted to a Class A EQ product through the advanced alkaline stabilization Bioset process.  Crawford, Murphy, and Tilly Engineers coordinated the pilot study for the District.

Prior to the pilot study, the plant operations team was leaning toward using belt presses for their future dewatering needs.  They had familiarity with belt presses and they were concerned that screw press technology did not have the capability to meet their requirements of 2660 dry pounds per hour without having to install a large number of screw press machines.  They were basing their concerns on historical screw press throughput capability based on their market research.

Springfield_Demo_Image_1-1

(Pilot Study Setup at SMSD Sugar Creek Plant)

During the pilot study, the Schwing Bioset team brought their FSP 600 screw press machine to dewater the partially aerobically digested WAS.  The goal was to dewater the material to the highest percent solids, with an excellent capture rate, and also with the least amount of polymer consumption.  The dewatered product would then be passed along to the mobile Bioset operation, which is an advanced alkaline stabilization process that can produce a Class A EQ Biosolid end product that can be utilized as a fertilizer or a soil amendment. 

The first week of the demo was utilized to optimize the screw press performance, and the second week to monitor continued performance of the screw press while utilizing the Bioset operation to produce a Class A EQ product. The purpose of this was to monitor the product over a couple month period to determine the stability of the Class A EQ product at the Springfield plant.  Over the two weeks, the FSP 600 screw press unit produced a dewatered product of 30% solids on average, even while operating the machine at 130-150% of design throughput capability.  After polymer optimization, the end result was realized with 14 pounds of active polymer per ton and the capture rate was above 95% during the entire two week period.  During the second week of the pilot, the Bioset system was utilized the entire time and was successful in producing the Class A EQ product.

Based on the successful results of the pilot, SMSD gave Crawford, Murphy, and Tilly the direction to design the new biosolids handling facility to include two high-performance screw presses, each capable of dewatering 1330 dry pounds per hour.  Although they liked the simplicity of the Bioset Class A operation, they were uncertain if the need for Class A was justified for the new facility.  They settled on a Class B Bioset system that utilizes all of the components of the Class A design, except for the reactor.  Space was left in the building to install the reactor in the future should Class A become necessary.  The job bid in December of 2014 and Schwing Bioset received an order for the two high-performance screw presses and the Class B alkalization system in early 2015. 

These FSP 1102 screw presses showcase the capabilities of high-performance screw presses and offer larger plants an appealing alternative to traditional belt filter press or centrifuge dewatering.

To learn more about our screw presses, Bioset process, and/or this project specifically, contact a Schwing Bioset Regional Sales Manager, call 715.247.3433, email us, and/or visit our website here.

Springfield_Demo_Image_2-1

(Class A EQ product at 44% solids)

 

 

Tags: Class 'A' Biosolids, Bioset Process, Alkaline Stabilization, Class AA/EQ Biosolids, Biosolids, Wastewater Treatment, Screw Press, Dewatering

SBI Installs New Beneficial Reuse Bioset System in Northern Minn.


FOR IMMEDIATE RELEASE

Schwing Bioset Announces New Beneficial Reuse Bioset System Installation in Northern Minnesota

The Bioset System will enable the Coleraine/Bovey/Taconite Joint Wastewater Commission to produce a soil amendment that meets the USEPA Class 'A' standards year round

Itasca County, MN- In Q3 of 2009 Schwing Bioset was awarded the contract to provide a Bioset System to the Coleraine/Bovey/Taconite Joint Wastewater Commission. This system was the lowest cost when compared to other technologies, and it produces a USEPA Class ‘A’ end product, unlike the other technologies that produced a USEPA Class ‘B’ material. The installation was completed in Q2 of 2011 and is fully operational.

The existing digesters could not meet the USEPA Class B standards in the winter months so the Commission needed to find a solution. After a reasonable amount of due diligence, the Commission secured the services of a local consulting engineering firm to explore alternatives for meeting the USEPA standards year round.

The engineer was faced with several challenges as they began their investigation. The plant was small, processing 0.5 MGD, and most available technologies would not scale down well or work well with intermittent biosolids processing. Another challenge was related to protracted winters and the need to find a place to store Class ‘B’ materials until the ground thawed and the biosolids could be land applied on the Commissions’ hay fields.

After considering options of a new digester, retrofitting the existing digester with heat exchangers, and reed beds, ultimately the Bioset process, Schwing Bioset’s alkaline stabilization process, was selected as the best available technology to meet these challenges.

About Schwing Bioset

For more than 25 years, Schwing Bioset has been helping wastewater treatment plants, mines and power generation customers by engineering material handling solutions. Schwing Bioset’s custom engineered solutions can be found in hundreds of wastewater treatment plants in North America as well as mines and tunnels around the world.

###

 

Tags: Biosolids Processing, Bioset Process, Alkaline Stabilization, Class 'A' Materials, Biosolids, Wastewater Treatment

Managing Cost, Air Quality and Odor Control with Schwing

Case Study: Ellsworth, WI

The West Central Wisconsin Biosolids Facility (WCWBF) is a regional biosolids processing facility in Ellsworth, Wisconsin, serving Ellsworth and over 20 neighboring communities. The biosolids are dewatered by centrifuges to 20-24% total solids. The dewatered sludge enters an alkaline stabilization system that mixes the sludge with lime and fly ash to yield a Class A product. The treated biosolids are stockpiled in a 37,000-square-foot covered storage building, and beneficially reused semi-annually by local farmers.

In 2008, WCWBF decided to upgrade the lime stabilization process, with the main goals being to contain cost and maintain air quality and odor control. The existing mixer used open hoppers; between that and the fly ash, the system generated a lot of dust. Furthermore, the facility received periodic complaints from neighbors about the odor.

WCWBF chose a Schwing-Bioset system employing a closed hopper, screw conveyors, and pressurized piping system to contain dust and odors. To avoid costly contract hauling charges, WCWBF had to achieve demolition of the old system and installation of the new Schwing-Bioset system within 10 days of shutting down the old system. Demolition and preparation took three days; Schwing Bioset's team installed the new equipment, including the electrical, within the remaining seven days.

With a few minor modifications to adapt it to the winter weather, the Schwing-Bioset system has performed within expectations since commissioning, achieving its goals of managing cost, dust, and odors.

Tags: Class 'A' Biosolids, Bioset Process, Alkaline Stabilization, Biosolids, Dewatering