CONTROLLED PYROLYSIS CLEANING OVENS

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1 The Pyrolysis Process Controlled Pyrolysis is one of the most effective methods of removing a plastic or paint coating from components. This process consists of heating the contaminated components at a precise controlled temperature in a low oxygen environment. This has the effect of vaporising the volatile constituents of any coating applied to the product. This vapour is passed though a second, high temperature chamber, which converts the volatile vapour into safe gasses that can be discharged to atmosphere. As the amount of volatile vapour increases, the temperature in the secondary chamber will start to rise. The increase in temperature, will initiate water sprays inside the main oven chamber, which reduces the production of volatile gasses to an acceptable level and the temperature in the secondary chamber will fall. To achieve the high level of flexibility required by our customers, every oven is provided with FOUR different pyrolysis profiles addition profiles can be added if and when needed. Environmentally Friendly Unlike traditional chemical cleaning methods, with all the associated problems of disposal of spent solvents; the pyrolysis process converts the vaporised coating to gases that consist primarily of water vapour and carbon dioxide. These invisible, harmless gases may be safely and legally discharged into the atmosphere.

2 Robust Our ovens are designed to last in an industrial environment. The inner surfaces of the oven can be lined in stainless steel. This enables them to survive the every day knocks that seriously damage the insulation in some ovens. As certain combustion processes can produce an acidic atmosphere, we have coated the inner surfaces of the exterior casing with an acid resistant membrane to resist corrosion. Advanced Technology Our ovens are PLC controlled allowing the pyrolysis profile to be custom designed for your application. All our ovens come with an integral GSM modem. This allows your process to be monitored by our specialist at our head office as needed. If required, adjustments can be made to your programme via the modem, eliminating costly down time waiting for a Service Engineer. In the unlikely event of a problem, we have facilities for data logging three days of your operations, to help identify the fault. Wide Range Our standard range has eleven oven capacities from cubic metre to 27 cubic metre and five model types; more than enough to suit the majority of applications. However should your requirements fall outside this range; we will design an oven to suit your needs. Service Out team of skilled Service engineers will ensure that your oven always operates to its optimum efficiency, and complies too the latest environmental regulations. An upgrade to an existing oven? Service work? A new Pyrolysis system? Whatever your requirements are, call us on The concept of a Cleanstrip Thermal Technologies Pyrolysis Oven for the removal of organic combustible materials. 1. The oven operates on a two-chamber principle. The temperature in the main chamber of the oven is loaded with the parts to be cleaned and raised to its pre set operating temperature anywhere in the range from ºC. 2. The temperature is gradually raised to the set point over a period of minutes depending on the size of the oven, amount of organic material to be removed and the metal mass contained herein to avoid any distortion of the parts. Simultaneously the oxygen content in the main chamber is reduced to a level that will not support combustion. 3. Under the effects of the heat in an inert atmosphere, as the temperature approaches the ºC range the organic materials coated to the metal parts start to break down to give off gas and smoke as volatile organic compounds. 4. The gas and smoke that are duly formed are drawn from the main heating chamber to a secondary pre-heated chamber or combustion tube, under the effects of a natural draught system, operating at a temperature in excess of 850ºC. The gas and smoke formed are held in the chamber for a min of 0.5 sec or 2.0 sec depending on the requirement of the environmental regulations in force to ensure total oxidisation of the constituent gas and smoke. Continued >

3 5. As the process cycle time continues the volume of gas and smoke increases to such an extent that if this were allowed to continue unchecked the volume of the smoke and gas passing through the secondary chamber or afterburner would overrun its ability to oxidise all the gas and smoke and therefore un-burnt particulates would pass to atmosphere as a pollutant. To ensure this does not happen the water injection system is activated when the stack gas temperature reaches a pre set temperature. The ensuing water spray injected into the main oven chamber reduces the temperature and consequently the amount of smoke and gas produced. Therefore, the volume of smoke and gas passing through the chamber, which is eventually emitted, to atmosphere remains well within the design parameters of the secondary chamber or afterburner to fully oxidise them into harmless carbon dioxide and water vapour. 6. The emergent environmentally friendly gas formed in the afterburner is then admitted to atmosphere via a chimney. 7. After a suitable cooling down period of approximately one hour, depending on the size of the unit the cleaned parts may be removed from the oven. The resultant inorganic inert material left behind in the oven by the cleaning process may be removed from the oven and placed in a container for normal waste disposal. B&M Longworth Engineering specialises in the manufacture and maintenance of Controlled Pyrolysis Ovens (burn off ovens), Curing Ovens and related gas and oil fired products for the Paint, Plastic, Automotive and Motor Rewind Industries. We are able to service, install and supply all makes and models of burners and heating equipment (Combat, Reznor, Powermatic, Hayworth, NuWay, Riello, Hamworthy, Weishaupt etc.) fuelled by either natural gas, LPG (liquid petroleum gas), or heating oil/diesel. We also supply spare parts at competitive prices. TECHNICAL INFORMATION (GENERAL) Please note that any figures quoted are related to using a Cleanstrip Thermal Technologies mid range oven and associated cleaning time. Times may be shorter or longer depending on the type of material to be removed the size of the oven and the metal mass. This will also affect the amount of fuel consumption. ELECTRICAL SUPPLY ELECTRICAL USAGE BURNER FUEL SUPPLY BURNER TYPE FUEL CONSUMPTION OVER AN AVERAGE FOUR HOUR CYCLE USING A MID RANGE OVEN SUPPLY LINE PRESSURES AND SIZES WATER SUPPLY PRESSURE AND MAX CONSUMPTION OVER A AVERAGE CYCLE CONTROL SYSTEM MAIN CHAMBER OPERATING TEMP AFTER OR SECONDARY BURNER OPERATING TEMP VAC 50/60 Hz Single phase, 13 amp fuse or to customer specification. All the ovens in the Cleanstrip Thermal Technologies range are designed to consume very small amounts of electrical power usually 2.6 amp 0.6 kw Natural Gas, LPG, Diesel or Kerosene Small package type. Main burner reverts to High /Low fire when the main chamber has reached its operating temperature. Natural Gas: Approximately 14 M³ of gas per hour. Over a four Hour cleaning cycle this equates to 56 M³. L.P.G: Approximately 5.7 M³ per hour. Over a four hour Cleaning cycle this equates to 22.8 M³. Diesel: Approximately 14 litres per hour or 56 litres over a four hour cleaning cycle. Natural Gas: millibar pressure on a 1 to 2 inch supply line L.P.G: millibar pressure on a 1 to 2 inch supply Line Diesel: Oil from header tank 8-10mm ID supply pipe Minimum 3 bar on a ½ B.S.P or 15mm pipe Consumption calculated as a max of litres per cycle as water spray is intermittent Programmable Logic Controller Ambient to 550 ºC. The following temperatures may be used as a guide for removing the following: Paint (cured and uncured) ºC Plastics ºC Varnishes/Resins ºC >850 ºC to ensure that all the volatile organic compounds are oxidised to give off carbon dioxide and water vapour as the main emission gases. Allowed to rise to a maximum 950 ºC before the water spray is activated. INSULATION Ceramic Fibre 100mm thick rated to 1250ºC Continued >

4 CARRIER CONSTRUCTION All steel construction, either fixed, roll in/out or via fork lift truck to customer specification All steel construction and seam welded (structural box section) Pyrolysis Ovens Standard Sizes Internal Usable Dimensions in Metres CHIMNEY EXEMPT FROM PG2/9(04) LEGISLATION RELATING TO DECONTAMINATION OF METAL PARTS (Applicable to UK only) TYPICAL EXPECTED EMISSION TEST RESULTS USING EPOXY POLYESTER PAINT. OXYGEN 8-12 (expressed as mg/m³ as a percentage) Stainless steel and fully insulated with ceramic fibre insulation As the maximum thermal input on the primary or main chamber burner is approximately 0.06 Mw on the Cleanstrip Thermal Technologies standard range of ovens the operator is not required to register the oven with the local authority as a controlled process as the limitation is set at 0.2Mw. This allows a thermal input burner capacity of 0.2Mw maximum on one oven before registration or the spread over separate ovens, as this is a cumulative total. The emergent gas emissions to atmosphere are also of such a trivial nature when removing a selection of resins and paints that exemption from registration from part 1 of the EPA is legitimately invoked. STATUTORY REQUIREMENT (UK ONLY) 6 (min) MODEL HEIGHT WIDTH DEPTH CAPACITY M³ CS CS CS CS CS CS CS TOTAL PARTICULATES (expressed as mg/m³) ORGANIC COMPOUNDS 5-6 (expressed as mg/m³) CHOLRIDES NIL (expressed as hydrogen chloride mg/m³) PERFORMANCE CHARACTERISTICS 20 (max) 20 (max) 10 (max) As the oven is operating only a heat haze may be seen from the top of the chimney. No particulate emissions should be visible or any odour detected. CS CS CS CS Ovens can be designed and manufactured to individual customer requirements. Please add the following suffix depending on your requirements; AE (automotive), MR (motor rewinds), PT (paint removal), PR (polymer removal) and SC (extruder screw cleaning).

5 B&M Longworth (Edgworth) Ltd Registered Office Longworth House, Sett End Road North Shadsworth Business Park, Blackburn, BB1 2QG, Fax