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[...]Plymouth + Maer Lane, Great Britain South West Water had been looking at alternative sludge dewatering technologies with lower TOTEX to potentially replace existing veteran centrifuge assets and tasked their preferred contractor Kier Utilities to offer solutions for the Plymouth Central and Maer Lane WwTW’s. HUBER worked closely with Kier Utilities, undertaking trials to demonstrate the HUBER Screw Press Q-PRESS® to South West Water operations who wanted to touch and feel the machine and satisfy themselves that the machine was simple, robust and easy to operate. The trial data not only satisfied South West Water that this, first of its kind in their region was what they needed but provided hard data to confirm Whole Life Costs in terms of power and chemical consumption as well as enabling accurate sizing. South West Water now have an alternative to centrifuges with a demonstrable WLC benefit together with operators who have bought into the equipment and are supportive of the change. 40 % polymer saving 80 % power savings (typical) 50 % saving on annual operating costs HUBER Technology have been working on establishing the Q-PRESS® as the go to technology for sludge dewatering. Sludge dewatering works extremely well on primary sludge and on larger sites sludge dewatering helps achieve a dryer cake, typically 18%- 30% for transportation and storage. When clients are looking at sludge dewatering, three technologies are generally considered: Screw Presses like the HUBER Q-PRESS®: Provide efficient , fully automatic, mechanical dewatering of sludge, low polymer usage Belt Presses: Although a well-established technology they are perceived to have high maintenance costs due to lots of moving parts, the belts are vulnerable to wear and blockage, spills are likely unless enclosed and they have a high wash water demand Centrifuges: Although again an established technology they tend to have high TOTEX although single units are capable of large throughputs which equals lower CAPEX, they have high power costs associated with them, high operator attendance is required, high wearing parts due to high rotation speeds and a single wash is required at the end of a shift which can overload the unit and spill out of the discharge end The HUBER Q-PRESS® has been an established product for the HUBER group and now has 1633 installations worldwide and 21 of those are UK installations. South West Water had identified sludge presses as an option to replace the centrifuge at Plymouth Central and compared HUBER’s Screw Press Q-PRESS® with another screw press technology, both technologies undertaking trials at Plymouth Central. Plymouth Central serves a P.E of around 320,000 and, being on a coastal port receives higher proportions of saline and fat than other in-land works typically do. Maer Lane serves a small population on the outskirts of Exmouth. On site previously was a 2002-centrifuge unit with 45 kW main drive and 7.5 kW back drive, which operated from around 6:30 AM to 9 PM as required, running at around 30 m³/h. HUBER’s Screw Press Q-PRESS® was demonstrated to have: Lowest NPV and WLC Lowest whole scheme capital cost Lowest operating cost Best technical support HUBER Screw Press Q-PRESS® sludge dewaterers are designed to provide efficient, fully automatic, mechanical dewatering of sludge once the diluted polymer dose into the feed sludge has been adjusted correctly to provide a suitable flocc. The enclosed design serves to reduce the odours, noise and the potential requirement for operator attendance due to spills that can be associated with other dewatering technologies on some sites. The low operating speed of the screw presses reduces wear and energy demand. For the trial to take place a HUBER Q-PRESS® 280 was tested on indigenous co-settled chemically assisted lamella-settled DensaDeg Primary and humus-like BAFF secondary sludge’s from the Plymouth Central site as well as imported similar sludge’s from the site at Maer Lane WwTW. The feed sludge during the trial varied from 4.6 to 5.15% DS with an average active polymer usage of 4.7-4.8 kg/tDS with an average cake dryness of 33% and minimum of 28.6%. As a comparison, the existing centrifuge was using around 8-10 kg/t DS of polymer based on a throughput of 25-30 m³/day to produce cake at around 23%. A sample of the trial results from a single day are shown in the table besides (click to enlarge). Following the successful trial HUBER were asked to tender for the supply of the permanent units for both of the sites at Maer Lane and Plymouth Central. The sludge feed at both sites was specified as 4.5% DS with a feed rate at Maer Lane of 10.22m 3 /hr and at Plymouth Central a feed rate of 35.55 m ³ /hr. Following a successful tender submission HUBER were awarded both projects and the HUBER Q-PRESS® 800.2 was selected for both sites with a single unit required at Maer Lane and three units required at Plymouth Central with installation and commissioning taking place in 2019. Whole Life Cost Comparison South West Water’s requirements were lowest WLC, low operator attendance, simple odour control availability and simple operation. Kier Utilities were keen to do a whole life cost comparison and using trial data and tender price as a thorough whole life cost evaluation, the following table summarises the comparison between the HUBER Q-PRESS®, new centrifuge technology and an alternative dewatering press technology, which was tested prior to HUBER. | HUBER Q-PRESS 800.2 | New centrifuge | Other dewatering press technology Average Polymer consumption|6 kg/tDS|10 kg/tDS|7 kg/tDS Power consumption (kW)|11|140|12 Cake quality (DS content)|30%|23%|25% M&E Capital Cost – HUBER Baseline 100|100%|64%|116% Total Scheme Capital Cost – HUBER Baseline 100|100%|106%|111% Annual Operating Cost Relative to current|-£298,208|-£150,666|-£223,539 NPV 20 yrs. HUBER based 100%|100%|130%|117% So what is the potential for the HUBER Q-PRESS® in the UK in the next AMP? Mike Willis, HUBER’s Business Development Director commented, “ We see the WLC benefits of the HUBER Q-PRESS® driving efficiencies in the sludge dewatering market as the cost of moving sludge is identified by OFWAT as a key efficiency driver. “ During the PR19 price, review OFWAT is expecting water companies to account for the sludge business separately from their wastewater business. The OFWAT consultation document has already highlighted the potential efficiencies through transporting sludge. This, together with the focus on regarding sludge as an asset rather than a cost is likely to result in more sludge being moved as well as focusing on the cost to transport. This needs to be done at lowest TOTEX. Reduced chemical, power and maintenance costs compared to centrifuge will drive ongoing OPEX savings year on year. Reduced odour emission rate of the Q-PRESS® compared to a centrifuge or belt press enables smaller, more efficient odour treatment plant, reduced risk of odour nuisance and improved working conditions for operators. The Q-PRESS® is available in four sizes and processes over 500kg/DS/h, providing a sludge dewatering technology that is more reliable, less fussy to operate, cheaper to buy and cheaper to operate than conventional systems- an ideal solution to meet the OFWAT objectives. The impact of the approach is considerable with a standard, modular design and approach- demonstrated by a single unit at Maer Lane and triple units at Plymouth. This has provided South West Water with a scale-able solution for their Sludge Dewatering sites. Kier Utilities and HUBER can apply the learning to the wider industry to deliver TOTEX efficiency across the industry. HUBER are involved in trials for another water company to develop a kiosk-mounted solution based on a standard off-site built HUBER Screw Press Q-PRESS®. At the beginning of March, the finalists were announced for this year’s Water Industry Awards 2020. HUBER Technology working with Kier Utilities and South West Water are delighted to have been shortlisted again for the third year running and as finalists in the following categories: Asset Optimisation Initiative of the Year - TOTEX savings at Plymouth Central Most Innovative Use of existing technology - Reshaping sludge dewatering[...]

[...]Birmingham, England A HUBER Technology Industrial Wastewater Case Study HUBER Technology recently completed a project for the largest confectionery manufacturer in the UK at their site at Marlbrook between Leominster and Hereford. The project for Mondelez which own confectionery brand Cadbury was delivered following good early engagement to allow a successful project to be delivered. Project Profile This project was part of the upgrade to the sites effluent treatment plant to include for a provision of sludge dewatering capability on site. It involved removal of an existing redundant DAF plant and the installation in its place of a HUBER Q-PRESS® sludge dewatering system including the provision of poly dosing equipment and associated control panels into the constraints of the existing building. HUBER Technology Supplied 1 x HUBER Screw Press Q-PRESS ® 440.2 Sludge Dewaterer 1 x Polymer dosing plant 1 x HUBER Control Panel 1 x HUBER Screw Conveyor Ro8 for sludge discharge Objective The sludge generated on site from the effluent treatment plant was originally tankered away and treated at another location. The installation of the HUBER Q-PRESS® sludge dewaterer enabled the sludge to be treated on site with just the sludge cake requiring disposal thus reducing operating costs. Solution Based on the parameters of 83 m³/week at 3% dry solids being generated at the site the Q-PRESS® 440.2 unit was selected. This allows the unit to operate in normal situations at around 8 hours per day 5 days per week. The capacity of the unit is approximately 4m³/hr if required. The sludge dewaterer was supplied complete with a HUBER designed control panel and a polymer dosing plant. Sludge cake was discharged directly into a Ro8 screw conveyor and into a skip for disposal off site. “This project was completed and delivered on time and to budget, this was achieved by early engagement with the client to ensure the right equipment was selected to deal with the sludge and was delivered successfully into the constraints of the existing building.” Richard Willis - Area Manager Product Profile HUBER Screw Press Q-PRESS®: The new generation of our well proved sludge dewatering press which is now even more efficient with an increased reliability in operation with optimised operating costs. With over 20 units operating in the UK and over 1,650 worldwide.[...]

[...]Mechanical sludge thickening to reduce sludge volume Before sludge with a very high water content is subjected to further treatment, it makes sense and is often necessary to reduce its volume by thickening. This also increases the solids content of the sludge. If sludge with a solids content of 1% is thickened to 6% solids, this gives a volume reduction of more than 80%. The thickening of the sludge is effected by separating sludge water; thin sludge becomes thick sludge, which is viscous but still pumpable. Sludge Volume Reduction Excess Sludge Thickening Sludge settles in gravity thickeners and is compressed by the weight of its own solids. Primary sludge from the primary clarifier of wastewater treatment plants and digested sludge from anaerobic sludge treatment thicken better statically than secondary sludge because of the higher density of their solids. Secondary sludge (excess sludge) from the secondary clarifier is preferably thickened mechanically separate from the primary sludge. Polymers are mixed into the thin sludge for flocculation before the sludge is added to the thickening machine. The sludge water released by flocculation drains by gravity through a filter medium (cloth or fine screen) while flocs are retained thereon. Mechanical excess sludge thickening is a prerequisite for the economic operation of anaerobic sludge stabilisation in a digester. HUBER offers various machines for sludge thickening differing in design, size and throughput capacity. We offer best-performing equipment for every application.[...]

[...]Various solutions for conveying dewatered and dried sewage sludge Sludge transport plays an important role in the planning and construction of sludge drying plants. On the one hand, the dewatered sewage sludge has to be brought into the dryer and on the other hand, the fully or partially dried sewage sludge has to be transported away from the dryer. When designing a particular transport solution, important criteria include not only the required transport capacity but also the sludge properties (moist, dry, sticky, dusty,...) and the desired degree of automation. Feeding and Removing Supply and Removal of Sludge at Drying Plants Feeding drying plants with dewatered sludge: The selected drying process – solar or belt or disc dryer – determines the way in which the dewatered sludge has to be fed to the dryer. HUBER has the right conveying solution for solar drying with the Sludge Turner SOLSTICE® as well as for the Belt Dryer BT and the Disc Dryer RotaDry® . Removing dried sludge from drying plants: Depending on the degree of dryness aimed for in the drying process, partially dried or fully dried sludge is present at the outlet of the dryer. The dried sludge must then either be conveyed to silos or containers or be incinerated.[...]

[...]The HUBER STRAINPRESS® Sludgecleaner SP 430 was introduced 4 years ago in response to the number of projects that required multiple SP 290’s. Many of the 290’s STRAINPRESS® supplied would’ve been single units, but on the larger sites like Five Fords in Welsh Water required 4 SP 290’s, Minworth & Coles Hill in Severen Trent required 6 & 4 SP 290’s respectively. The capacity of the STRAINPRESS® SP 430 is just over double that of the SP290. The flow rate of the SP 430 with a 5mm basket @3% ds sludge is 160M3/Hr compared to 75M3/Hr on the SP 290. Cost savings can be made by: Reduced number of units (including panels), Reduced gantry size, footprint, Minimise work time onsite, Reduced maintenance and power requirements. We have supplied 407 STRAINPRESS® Sludgecleaner SP 290’s to date in the UK. Since its introduction into the UK, we’ve supplied 14 STRAINPRESS® Sludgecleaner SP 430s in the UK, the largest of those project was a recent installation in SE London (see photo). Other projects at Esholt STW for Yorkshire Water and Southend on Sea STW with Anglian Water. AMP8 will see this number of units increase due to the size and location of the projected projects. Benefits High solids removal Low energy consumption 420+ UK installations Simple robust design Fully automated operation View a video demonstrating how this sludge screening solution operates: STRAINPRESS® Sludgecleaner SP - Animation[...]

[...]Efficient and reliable removal of coarse material from sludge For the operational safety of sludge treatment processes, it is advantageous if the sludge is as free as possible of coarse material and disturbing solids (e.g. paper, plastics, fibres and hair). Otherwise, repeated malfunctions of aggregates and processes may occur in pumps, but also during thickening, dewatering or drying, and these can be time-consuming and costly to rectify and require increased manpower. For the agricultural recycling practised in many regions of the world, it also makes sense to separate all solids such as plastic parts for reasons of environmental protection and aesthetics. Depending on the application, HUBER has different machines for sludge screening in its product range so that the right machine and technology is available for every application, every installation situation and any throughput rate.[...]

[...]Sludge Drying Cost reduction on sludge transportation and disposal costs. Efficient solutions to minimise the volume of sludge for disposal Wastewater sludge is dried to minimise its mass and to save sludge transport and disposal costs. Handling and storage of dried sludge is cost effective, and any further disposal and utilisation methods are possible. The dried product can be used as fertiliser, as well as fuel – the calorific value of fully dried sludge is similar to that of brown coal. Thermal energy from different energy sources Thermal drying involves the evaporation or vaporisation of capillary water, surface water and cellular water, which requires thermal energy. Typical energy sources are the sun (solar drying) as well as site-specific waste heat (e.g. from a combined heat and power plant) or excess steam from power generation (exhaust steam from a turbine). Similarly, energy-efficient heating solutions using heat pumps can be employed. Extensive mechanical dewatering of the sludge is necessary beforehand. Efficient solutions to minimise the volume of sludge for disposal Wastewater sludge is dried to minimise its mass and to save sludge transport and disposal costs. Handling and storage of dried sludge is cost effective, and any further disposal and utilisation methods are possible. The dried product can be used as fertiliser, as well as fuel – the calorific value of fully dried sludge is similar to that of brown coal. Thermal energy from different energy sources Thermal drying involves the evaporation or vaporisation of capillary water, surface water and cellular water, which requires thermal energy. Typical energy sources are the sun (solar drying) as well as site-specific waste heat (e.g. from a combined heat and power plant) or excess steam from power generation (exhaust steam from a turbine). Similarly, energy-efficient heating solutions using heat pumps can be employed. Extensive mechanical dewatering of the sludge is necessary beforehand. Solar Drying Solar drying of sludge uses the energy of the sun as a thermal energy source. The basic principle is that the sludge is dried in a greenhouse structure with the help of a mechanical sludge turning device. Convective Drying Belt dryers work with low and medium temperature and the sludge is convectively dried with hot air, whereby it can be simultaneously disinfected. The dried product achieves a solid concentration up to 95% DS. Contact Drying Disc dryers work according to the contact dryer principle: Designed for partial drying of dewatered sewage sludge, they are heated with saturated steam and used for medium to large sewage sludge volumes in combination with fluidized bed incineration. The right drying process for every application We supply three different kinds of HUBER sludge drying systems, which differ greatly in terms of space requirements, temperature level and heating medium. Solar Sludge Dryers In a greenhouse where a mechanical sludge turner is installed, the sludge is dried to a solids content of usually 65% DS. HUBER solar dryers are used on small and medium-sized wastewater treatment plants as well as on very large plants. Convective Dryers The sludge is dried either with cold or with hot air in a belt dryer. The dried product has a solid concentration ranging from 70% DS up to 95% DS. HUBER cold air dryers are designed for small sewage treatment plants while the medium temperature belt dryer are most suitable for medium to large treatment plants. Contact Dryers The disc dryer is a contact dryer designed for the partial drying of dewatered sewage sludge to 40 – 45% DR and is heated with saturated steam up to max. 10 bar(a). HUBER disc dryers are often used in combination with fluidized bed incinerators for medium to large and very large volumes of sewage sludge.[...]

[...]Great Britain Three recent installations are now helping poultry slaughterhouses to reduce their sludge disposal costs and remove their reliance on tankering sludge off site. Background With ever increasing sludge disposal costs and tightened restrictions on spreading sludge on land (particularly over the summer months), HUBER were approached to provide dewatering of the sludge on three poultry slaughterhouses. The sites had identified the potential for savings and wanted to evaluate treatment options. Since the three sites operate similar processes, a single trial was conducted to evaluate the screw press performance. HUBER were able to offer an on-site trial using a containerised HUBER Screw Press S-PRESS unit, which was operated by site over the course of a month. This allowed the sites to confidently assess not only the performance of the machine but the ease of operation and minimal amount of time required from site operatives. Following the trial, the client was issued with a detailed report, so that they could evaluate both capital and operating costs. Solution Although the Screw Press and polymer batching plant supplied to each site was the same, each site had slightly different considerations for installation of the Screw Press on their site, including: Area available and layout of existing treatment plant, including location of sludge holding tank Size of skip/trailer to be used for cake disposalExisting buildings/structures HUBER have experience of operating Screw Presses mounted in containers, inside buildings, and on top of gantries with cake either dropping into a skip directly or using a screw conveyor to transport & distribute the cake across a long trailer. The customers were able to draw upon this knowledge to ensure that each installation was as practical as possible and cost effective, while being the right decision for that particular site. HUBER provided the full equipment scope for the client to incorporate into their installation, including: HUBER Screw Press S-PRESS I sludge dewatering screw press Automated polymer batching plant to flocculate the sludge Feed sludge and chemical dosing pumps In-line polymer injection and sludge mixing to mix sludge and polymer within an enclosed, small footprint Pre-programmed control panel to automate operation of the plant As a result of the three installations, the clients are have been able to significantly reduce their sludge disposal costs. In addition, vehicle movements are minimised, since the water removed from the sludge now goes to drain (after being processed by the on-site ETPs) rather than being transported away by costly road tankers. Key figures: Sludge @ 3.3% DS Dewatered Cake @ 23% DS Polymer usage 10 kg/tDS For more information please contact +44 1249765000, email rotamat@huber.co.uk[...]

[...]Solutions for cost-efficient sludge dewatering Sewage sludge produced in municipal and industrial wastewater treatment plants requires dewatering prior to further treatment or utilisation. Rising costs for sludge disposal make it necessary to concentrate the sludge to a high solids content. Mechanical sludge dewatering is used to reduce the amount of sludge by separating sludge water. A more or less firm sludge cake is produced. Prior to its dewatering, fed sludge is first flocculated by addition of polymers (sludge conditioning). Sludge Conditioning Economic Sludge Dewatering For the economic operation of a sludge dewatering system, sludge conditioning plays a very important role in addition to selecting the right dewatering unit. Not only is it important to select the right flocculant and to ensure optimum dosing (concentration, quantity, dosing point), but also to mix the flocculant properly into the sludge to achieve good floc formation, which then leads to an optimum dewatering result. HUBER offers various machines for sludge dewatering and, based on decades of experience and thousands of installations, can always design the best suitable solution for different throughputs and different sludge qualities. The overall solution of a modern sludge dewatering system also includes the transport of the dewatered sludge to further sludge treatment or to intermediate storage (container or bunker). Here, too, HUBER has extensive expertise and can provide tailor-made solutions for the transport of sludge .[...]

[...]Wanlip - Leicester, UK A HUBER Technology Wastewater Case Study HUBER Technology recently completed a project for Severn Trent Water at Wanlip STW on the outskirts of Leicester. This was a project that had been looked at for a long period of time but was commissioned in early 2020. Project Profile This project was part of the upgrade to the sites indigenous sludge treatment to replace ageing step screens, which were installed in the 1990’s. HUBER Technology were first involved in the project in the late 2000’s to see what options were available to improve the process. The challenge was to improve the sludge screening on the site but we were constrained by the location of the screens at high level receiving the pumped sludge. HUBER Technology Supplied 2 x HUBER Sludge Acceptance Plant ROTAMAT ® Ro3/1200/6 tank mounted sludge screens 2 x HUBER Severn Trent Water specification control panel Objective The primary objective was to improve the sludge screening on site to prevent screenings that had bypassed the inlet works entering the picket fence thickeners and further downstream parts of the treatment process within the constraints of the high-level sludge screening area. Solution As outlined above this was a project that HUBER Technology had been involved with for a long time with various contractors. We had previously looked at utilising the existing 600mm concrete channels but these were no longer wide enough for the increased flow rate. The current screens were installed in a building but this was deemed to be beyond repair and was removed, this allowed clear access for the new screens. The tank mounted screen were mounted alongside the existing channel retaining the original upstream balancing tank. Flow from the balancing tank then flowed to each of the two screens whilst maintain a bypass channel between the screens if it was required. The screens sludge was discharged back into the original channel prior to it being fed to the adjacent picket fence thickeners. Each screen was provided with its own dedicated control panel fully built to Severn Trent Waters specification. Product Profile HUBER Sludge Acceptance Plant ROTAMAT ® Ro3 – The robust and efficient Ro3 has become the most popular system of its kind. Its superior design and engineering guarantee the most dependable operation day after day, year after year. The main component of the Sludge Acceptance Plant ROTAMAT® Ro3 is the reliable Fine Screen ROTAMAT® Ro1. It excels with its high capacity, good separation efficiency and low head loss. Another exceptional feature is its integrated screenings press with all its benefits. The Fine Screen ROTAMAT® Ro1 is extremely sturdy, able to deal with rocks and grit, and entirely made of stainless steel. It is fully self-cleansing as its rake tines fully engage the basket bars. With over 500 units installed in the UK and just under 100 supplied to Severn Trent Water since 1988. “Having been involved with this project for over 10 years it’s great to see finished solution completed on site at Wanlip. Severn Trent Water should hopefully see the huge benefit this technology brings to the downstream process very quickly.” Richard Willis-Area Manager Key Features & Benefits High capacity to minimise waiting time for tank discharge High separation efficiency Often used with Sludgecleaner STRAINPRESS® to provide a robust 2 stage sludge screening and dewatering process Automated operation of the raked bar screen Fully enclosed to eliminate odour Intergrated screenings washing and compaction in a single unit Low maintenance - fully self cleaning as its rake tinesfully engage with the basket bars 500+ successful UK installations[...]