WET News

The mobile computer-controlled grout mixing and supply van used to prepare the spray lining grout of approval HUBER TECHNOLOGY Sludge Thickening and Dewatering Solutions Small footprint with enclosed design. Low power, polymer and washwater consumption. Wide product range suitable for thin/difficult sludges. Containerised, mobile or skid mounted. Low OPEX – due to slow drum rotation. Transport costs reduced with onsite processing. Sizes suitable for small, medium and large throughput application sites. impact drill is used to drill through the manhole wall into the substrate for grout injection operations. The drills are also used to remove any damaged or loose material prior to applying spray lining. Cleaning of the manhole sur- faces is carried out using a high pressure rotary cleaning head that is adjusted to suit the size of manhole. The head is opened up using a threaded rod and only takes seconds to adjust. The grit can be introduced to the water using a venturi affect and this scours the surface of the chamber removing hardened deposits. This leaves the surface 'keyed' so that when the mortars are applied they can effectively bond to the old manhole surfaces. The grout injection system uses the same mixers and pumps. The mixture is then pumped through high pressure hoses to a grout injection gun. The grout is pumped until back pressure is recorded on an integral pressure gauge. The system can also pump through a small injection nozzle where smaller quantities of grout are needed. These are then cut off and the injection holes are filled with rapid set mortars. Shading effect The spray lining is carried out using the same winch and frame and computer-controlled set up. The tolerances, dimensions and required lining thicknesses lining are programmed into the com- puter and this then works out materials required. These materi- als are then loaded into the mor- tar hopper. The system is set by lowering the spray head to its lowest point in the chamber then the highest to establish the required travel limits in the manhole. The computer determines water quantities for mixing and the speed at which the pump should run to provide the required liner thickness. On com- pletion the system is then purged and cleaned. The whole rehabilitation pro- cess follows the simple routine of high pressure cleaning, grit blast- ing, joint sealing, grout injection and finally spray lining. The spray lining is applied using centrifugal spray heads or by wet spraying methods, this coating is applied to a recom- mended thickness of 10mm. The final curing time is 120 hours and the final strength is 80N/mm2, but this coating is structural and can withstand high ground water pressure once fully cured. From Anglian Water view- point, using this system was also more of a full rehabilitation rather than as a temporary fix. Due to the size of this contract it was important for the technique used to a reliable one that was also quick to apply. The road layouts and tight working spaces involved at site also meant the rehabilitation sys- tem used needed small footprint equipment, for which PBF's 3.5t vehicle was ideal. Stern concludes: "This is the largest single project of its type to be awarded to date in the UK that we are aware of. The integrated computer system for data collec- tion ensures all material usage, spray coating thicknesses and grout injection quantities can be downloaded and a full report can then be provided to the client." Utility Week™ Live incorporating IWEX will be the UK's first (and only) event dedicated to the business, operational and technical needs of the UK's water, electricity and gas utilities, from upstream, transmission and distribution through to domestic and non-domestic retail. Building on the rich heritage of IWEX - Faversham House's long-standing water and wastewater exhibition - Utility Week TM Live incorporating IWEX will provide an important information exchange and market place for the UK's multi-billion pound utility industries and an ideal environment for exhibitors to do business. Whether your organisation is selling specialised equipment, technology or know-how into a specific segment of the market - or your expertise is equally relevant across utilities - Utility Week TM Live incorporating IWEX will deliver the audience you need to succeed. Why you should exhibit: ✓ Extend your competitive advantage by exhibiting your products and services in an environment dedicated to the UK utility market, or engaging with the audience via sponsored features and networking opportunities; ✓ Do business and network with thousands of relevant, engaged buyers; ✓ Leverage your ROI further across Faversham House's extensive portfolio of business information products. To book your stand or request further information, please contact the sales team: Nicky Shaw – energy sector +44 (0) 1342 332070 nicky.shaw@fav-house.com Rachael Lyon – water sector +44 (0) 1342 332097 rachael.lyon@fav-house.com utilityweeklive.co.uk BOOK YOUR STAND TODAY The new event dedicated to the UK's water, electricity and gas utilities WATER & WASTE WATER TREATMENT ASSET MANAGEMENT SMART GRIDS METERING & MONITORING GENERATION Co-located with: Organised by: Supported by: Brought to you by the publishers and organisers of: Gold Sponsors: INCORPORATING 21-23 APRIL 2015 NEC BIRMINGHAM UK Spray lining underway in a fully prepared manhole Access to some of the manholes was deemed to be one of the major problems that would be encountered during the project duration as certain manholes were located within gardens and fields DECEMBER 2014 WET NEWS 15

• Cover