Water and Effluent Treatment Magazine
Issue link: https://fhpublishing.uberflip.com/i/374689
SEPTEMBER 2014 WET NEWS 23 SEPTEMBER 2014 WET NEWS 23 Z-Tech and Siemens now offer: • 12 hours - restore your flowmeter telemetry • 24 hours - emergency flowmeter replacement Designed to make life easier for the water industry, we challenge you to try this new nationwide service. Our 24/7 manned helpdesk is waiting for your call! 01223 653500 z-tech.co.uk Finally! Next day flowmeter replacement Accessorize your pump hire • Temporary installations • Environmental products • Cost effective solutions When pumps are needed to move water, wastewater or sludge, selecting the correct hoses and accessories is essential to ensure that tasks are carried out safely and efficiently. The comprehensive Sykes Pumps range ensures that, whatever the application, you can hire what you need. A Accessories available for hire include: hoses, fittings, control panels, settlement tanks, drip trays, fuel tanks, road ramps, venturi jet aerators and many more. The Sykes Pumps range of hoses and accessories has been selected to complement the full range of pumps available for hire, meaning you can source everything you need from one supplier, reducing purchasing time, paperwork and cost. surface area of the OdourPack enhances this mass transfer. Contrary to random packing materials (including lava rock / pumice stone), the characteris- tics of the OdourPack with all its surface available for biomass growth and without internal pores that can get clogged, pro- motes biomass detachment to keep a thin biofilm that reduces resistance to diffusion of oxygen and pollutants within the bio- film, besides facilitating the wash out of the sulphuric acid produced from the H2S removal (i.e. lava rock / pumice stone is degraded under acidic condi- tions, reducing its life time). Bio-degradation This is of great importance, since having an adequate bio- film allows the system to be able to treat peak concentration of pollutant above average condi- tions, and avoids thick biofilms where oxygen can limit the bio- degradation process releasing odorous intermediate com- pounds such as carboxylic acids or elemental sulphur that can clog the packing. It is well known that when bioreactors are operated at high residence times performance increases, so the high porosity of OdourPack (>92%) allows a higher real residence time com- pared to packings with lower void fraction. In pall rings or The Odour Pack winded plastic packing media inside the vessel serves as the support material for the development of the biofilm lava rock / pumice stone the increase of porosity implies a great decrease in the specific surface area, which is a critical parameter of the process. Compared to OdourPack, random packings with low porosity have higher pressure drop values, which increase with lifetime as porosity decreases because they do not promote biomass detachment. In addition, the OdourPack is chemically resistant with a life time guarantee of 20 years, and its light weight but strong struc- ture allows placement of layers from 1m up to 9m of height with- out compaction and without plastic debris that can clog water pipes downstream. If necessary, the OdourPack can be easily removed and installed again in the bioreactor vessel. The PLC allows very easy control and data acquisition via internet / plant SCADA, and also automatic control and optimisa- tion of the water usage based on a pH value of 1.7 units of the drained water. This pH control is important to promote a gradi- ent of pH along the OdourPack, which enhances the growth of both autotrophic and hetero- trophic bacteria for the removal of H2S and organic compounds (VOCs and mercaptans) respec- tively in the same bioreactor, without increasing the water usage compared with systems which recirculate the water. The low water usage (from 0.25m3/hr to 5.24m3/hr depend- ing on the H2S load) and discon- tinuous spraying regime has a great impact on energy saving costs, as the pressure drop of the Sulphus is very low, with average values between 150Pa- 500Pa depending on the water usage. Whereas in the last decade it is already proven that the results of the biotrickling filters with synthetic media are at least as good as conventional technolo- gies, Pure Air Solutions says the UK can also save a lot of energy, consumables and money. At the sewage treatment works in the North-east, using the Sulphus instead of a chemical scrubber the savings in chemicals amounted to more than £207,000 a year, and there are savings in energy consumption as well as in the maintenance work (chemical scrubbers are a more complex technology) which should still be added to the opex savings. n