Dokumentation Tischgaswäscher Typ DGE-TGW Documentation table gas washer type DGE-TGW Documentation laveur de gaz de table type DGE-TGW

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1 Dokumentation Tischgaswäscher Typ DGE-TGW Documentation table gas washer type DGE-TGW Documentation laveur de gaz de table type DGE-TGW Tischgaswäscher Kompaktanlage mit fahrbarem Tisch für eine Arbeitsplatzabsaugung. Abluftmenge : m³/h Schadstoff : Ammoniak Chemosorption mit 20%-iger Schwefelsäure Table gas washer Compact plant with mobile table for a workplace exhauster. Exhaust air quantity: m 3 /hr. Pollutant: ammonia Chemisorption using 20 % sulfuric acid. Laveur de gaz de table Installation compacte avec la table mobile pour une aspiration de lieu de travail. Quantité d air d échappement : m 3 /h Polluant : ammoniaque Sorption chimique avec d acide sulfurique de 20 pour cent. DGE-TGW Table gas scrubber documentation in English

2 Contents 1. Introduction 2. Description 2.1 Design 2.2 Description of function 2.3 Capacity parameters 3. Design types 3.1 Basic type 3.2 Structure with a self-controlling operating range 4. Field of application 4.1 Chemisorption 4.2 Absorption 5. Examples of application 5.1 Chemisorption 5.2 Absorption 6. Equipment designs 6.1 Common design 7. TGW-type series 8. Safety instruction 8.1 Safety regulations 9. Maintenance instructions 9.1 Service partners 10. List of spare parts Enclosure Instruction All data, illustrations and specifications contained in this documentation are information valid in the time of their publication. We are reserving the right to make changes at any time.

3 1. Introduction The table gas scrubbers are scrubbers serving for purifying exhaust waste air and they have been designed to serve for small quantities and very small flow rates of air exhausted from workplaces and laboratories. The gas scrubber system developed by the firm DGE GmbH enlarges the range of products, laboratory gas scrubbers by plants designed to serve for minimum flow rates of drawn off air. The developed table gas scrubbers make it possible to maintain limit values given by legislative for exhausting the drawn off air directly from the place of occurrence. In this way they are ensured safely values lower than MAK values. In spite of a simple structure the table gas scrubber is fitted with an instrumentation ensuring all the time safety of operation. 1.1 Field of application The field of application of the table gas scrubbers covers many fields of industry and municipal economy system. As the main field of application in industry they are considered to be laboratory equipments. In this case the table gas scrubbers can serve as mobile gas scrubbers or as an equipment installed firmly in a chapel. Further fields of application are in the field of a small and very small extent where small flow rates of exhausted air have to be purified. These fields are for example soldering places, very fine mechanics, handicraft, gold and silver processing, microelectronics however, in that case the exhausted air is saturated with harmful substances as for health. These processes exist also at processes of transferring small quantities of compounds. These activities exist among other also in a municipal economy system as for example in hospitals, workshops, schools and universities. 1.2 Pollutants The table gas scrubber purifies acid or alkaline pollutants as NH 3, amines, SO 2, HCl, HF, HBr, P 2 O 2, HNO 3 a.s.o. from the exhaust air. For that you have to use the suitable washing medium (acid or lye).

4 2. Description 2.1 Design The table gas scrubber consists of a two-stage scrubbing system formed by a jetting gas scrubber and a subsequently installed gas scrubber filled with small solid bodies. In this way it is guaranteed a high gas scrubbing capacity and very often there is no need to carry out any additional treatment of the drawn off air. Both the systems are arranged in one body, therefore, they are accessible easily for carrying out maintenance work. 2.2 Function principle A scrubbing solution necessary for the scrubbing process is at disposal in the washing agent storage tank. It is fed through filling branches. State of filling can be checked visually. By switching in the table gas scrubber a circulating pump is put into operation and both the gas scrubbers are supplied with washing liquid. The jetting gas scrubber has been designed so that inside the gas scrubber there is underpressure, therefore, on workplace there is not necessary to install any other additional fan for exhausting air. In case of need, however, it is possible to include in the system a piping fan. With the use of a conductivity measuring probe installed in the washing circuit and with the help of concentration measuring in the clean gas it is possible to monitor continuously the gas scrubbing capacity of the table gas scrubber. An additionally installed working hours counter makes it possible to monitor time of using the washing solution. In this way they are installed three mutually independent control criteria to control the capacity of the table gas scrubber. 2.3 Capacity parameters The table gas scrubber is a high-capacity gas scrubber for minimum flow-rates of air. They do exist 4 basic types for rates of flow of exhaust air from 5 to 250 m³/h. An attainable separation capacity at chemisorption is higher than 99.9 % at an average time of use of the washing solution in operating storage tanks of 4 weeks. The washing solution consumption is reduced above all by the fact that the table gas scrubbers are switched in only in cases when the corresponding processes are carried out on the workplace. Therefore, it results in a marked reduction in the consumption of chemical compounds when compared to plants of central type for purifying the exhaust air. A pressure increase for exhausting the drawn off air is of about 3-5 mbar. It is possible to increase exhausting capacity by installing the fan in the piping.

5 3. Design type The table gas scrubber consists of a base plate on which the gas scrubber system is installed. The frame is covered with a removable sheathing. 3.1 Basic type The size of the basic type is 800 x 500 x 600 mm (LxWxD) and it can be placed either on a table or directly into a laboratory chapel. A mass is of approximately 30 kg, therefore, the plant is a mobile plant. The basic type consists of the following structural members: Instrumentation MSR instrumentation Jetting gas scrubber Filling state control Gas scrubber with small bodies Operating hours counter Circulating pump ON/OFF switch The basic type can be delivered in four basic sizes and the cover size is always the same Additional equipment The following additional equipment can be installed as optionals: Instrumentation Fan installed in the piping MSR ph measuring Conductivity measuring Purified gas measuring Recorder Other additional equipment or execution for extreme conditions are delivered on request. 3.3 Design type with a mobile table To ensure a flexible use it is possible to deliver a table gas scrubber fitted on a mobile table. Points from where the air is exhausted can be connected easily with the use flexible hoses.

6 4. Field of application The table gas scrubber is suitable above all for purifying small flow rates of exhaust gas which is contaminated with inorganic or organic substances as acids and lye. 4.1 Chemisorption The table gas scrubber is equipped with two stages of washing, i.e. a jetting gas scrubber and a scrubber filled with small solid bodies. The calculation of a necessary number of theoretical stages NTU for a given separation capacity is carried out in the following way: NTU = ln (Y E /Y A ) Y E - inlet concentration of components in the waste gas Y A - outlet concentration of components in the waste gas The height of separation degree of a gas scrubber fitted with small solid body filling is calculated in the following way: Z = NTU * HTU Z - height of the gas scrubber fitted with small solid body filling ex pressed in m NTU - number of necessary separation stages HTU - height of theoretical separation degree By installing before a jetting gas scrubber it is already attained one NTU as a minimum, therefore, it is possible to realize using a table gas scrubber in total 3-5 NTU. 4.2 Absorption Good results of absorption can be obtained in such cases when for the scrubbing process is not used a closed water circuit, however, in cases when the table gas scrubber is operated with the use of fresh water. The attainable separation capacity corresponds to a value of about 1 NTU in that case. During operation with a closed circuit it is necessary, however, to take into consideration absorption and desorption effects. As opposed to the method of calculation for chemisorption it is necessary at absorption to take into consideration additionally also phase equilibrium Y E,A = C E,A * H i C - concentration of components in liquid phase H i - Henry s coefficient of component i From this limitation it is obvious that with the use of absorption it is possible to attain a good separation capacity only in substances well water-soluble as for example ammonia.

7 5. Application examples 5.1 Chemisorption A flow of the exhaust air with a flow rate of 50 m³/h is NH 3 saturated in a concentration of 50 mg/m³. A quantity limit of odour disturbance of environment is about of 3 mg/m³. For solving the task it is necessary to use the following theoretical number of stages: NTU = ln(50/3) = 2,8 As a washing agent it is used 20 % sulphuric acid. On the basis of tests the following separation stages have been found for DGE-TGW type: Jetting gas scrubber 2,0 Gas scrubber with small solid bodies 3,0 In this way it is possible to solve the given task with the use of the table gas scrubber so that the waste gas with 5 NTU is washed to a value of 0,3 mg/m³. Transfer units of different components form a firm know how and they are taken into consideration in any calculation. 5.2 Absorption The calculation of absorption can be carried out in advance only approximately for the reason of a complex mass transfer. It is purposeful to carry out a pilot trial to find a separation efficiency. When starting from the maximum theoretical transfer unit NTU = 1 it is possible to realize with water absorption a maximum separation efficiency of about 60%. In this case it is not necessary to install any circulating pump. The jetting gas scrubber and gas scrubber filled with small solid bodies are supplied directly with fresh water. The saturated scrubbing water is discharged directly from a common sludge storage tank.

8 6. Equipment designs The basic structure of the complete table gas scrubber is shown on the method diagrammatic plan included as a part of the enclosure. The equipment consists of the following assemblies: - Jetting gas scrubber K 01 - Gas scrubber filled with small solid bodies K 02 - Washing water storage tank and relaxation tank B 01 - Demister F 02 - Circulating pump P 01 - MSR instrumentation By means of these assemblies the automatic operation of the waste gas purification can be realized. 6.1 Common design For fully automatic operation of the table gas scrubber it is necessary to apply only filling state control as a protection of the circulating pump against idle running. Additionally, it is possible to install the following equipment: ph value measuring Conductivity measuring Purified gas measuring 7. Table gas scrubber type series For the use of the table gas scrubbers they do exist 4 different assemblies for purifying exhaust gas flow with a flow rate of 5 to 250 m³/h. Type designation of the table gas scrubber is formed in accordance with the following scheme: DGE-TGW-D1/D2-A-B It means in this case as follows: DGE firm name TGW table gas scrubber D1/D2 FKW/SW -type S/T stationary or mobile execution A material used B year of manufacture With the use of that classification the delivered table gas scrubbers can be unequivocally classified and their service ensured.

9 8. Safety instructions In principle, with the exception of instructions stated in the handed over documentation the user shall observe also local regulations in force in the place of the equipment application. Operators and personnel shall be acquainted with the documentation and shall be provided with an authorization for carrying out necessary appropriate activities. The user undertakes to use for operating the table gas scrubber an instructed personnel only. 8.1 Safety regulations Regulations which shall be observed are included in the documentation of the appropriate equipment. In addition to it, it is necessary to observe regulations specific according to place of application of the equipment. Above all, it is necessary to check whether: - Operating instructions are kept close to the appropriate equipment - The equipment is handled and operated by an authorized personnel only and that the appropriate personnel has been instructed - The cleaning of the equipment is carried in regular time intervals - Safety devices and equipments are checked after each 6 months - For operation of the equipment have been created no other conditions than those stated in the contract. Change in design can be carried out only when approved by the equipment manufacturer. Instruction The observance of safety instructions and safety regulations is a precondition of troublefree operation.

10 9. Maintenance instruction It is necessary to observe maintenance time intervals as stated in the maintenance instruction manual. The maintenance work can be carried out with the appropriate equipment switched off. 9.1 Service partners When concluding a contract it is necessary to appoint a partner responsible for service of the equipment. Before the service has been carried out it is necessary to be supplied well with necessary spare parts. 10. Spare parts For ensuring trouble-free operation of the table gas scrubbers it is necessary to have on stock a minimum amount of spare parts. This is, however, very necessary in view of a long delivery time in case of the special spare parts. These special spare parts are as follows: 1 gas measuring sensing unit 1 liquid for ph value and conductivity measuring Other spare parts are always given by a specific mode of use. Instruction Regular maintenance and a stock of spare parts are necessary for ensuring troublefree operation and for increasing applicability of the equipment.

11 Enclosure 1. Basic flow sheet/flow diagram 2. Table scrubber P&I diagram 3. Table scrubber lay-out 4. View from the back with sheathing dismantled 5. Data sheet

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14 Table gas scrubber Back side without covering App. 3

15 Environmental Protection Process Engineering Plant Engineering überwacht DGE-Standard Model Range DGE-TGW for table gas washers for exhaust air decontamination DGE-table gas washers are high-performance washers for exhaust air decontamination in workplace ventilation systems. The DGE-TGW model series of DGE-table gas washers consists of self-suctioning jet gas washers and packed washers. When a self-suctioning jet gas washer is used, no further exhaust air ventilation system is necessary. With the installation of a pipe ventilator, the DGE table gas washer can be used in a variety of ways. In addition, the unit is compact and mobile. DGE-table gas washers are designed for the following uses: dust and aerosol separation with small particles and pre-cleaning for absorption and chemsorption in jet gas washers for absorption and chemsorption in packed washers A heat exchanger can be attached in the wash cycle for cooling exhaust gases and for drawing off the heat from solutions and reactions. The performance of the packed washer can be set for one or more stages and is carried out with a drip-separator. The running of the wash cycle depends on what task is to be carried out and can be monitored with an acidic or an alkaline ph-value. For particular tasks, the laboratory gas washer can be installed with an activated carbon filter as ringsorber. Alternately, a reader can be installed to measure the concentration of pure gas. Clean Gas Water Crude Gas ➊ ➌ ➍ ➋ LI Evacuation Special solutions are offered for external applications. DGE-table gas washers are manufactured in steel, high-grade steel or synthetic materials such as PE, PP, PVDF and GFK. Models made from synthetic materials are resistant against corrosive elements. The column design is built to work simply and to be run by the customers themselves. DGE-table gas washer Model range DGE-TGW 1 Self-suctioning jet gas washer 2 Packed washer 3 Circulation pump 4 Pipe ventilator DGE GmbH Hufelandstraße Wittenberg Tel.: +49-(0) Fax: +49-(0) DGE-INFO@t-online.de Internet:

16 Environmental Protection Process Engineering Plant Engineering überwacht These are the standard models of DGE-table gas washers TGW for exhaust air decontamination: Model Exhaust Air Decontamination DN DN Ammount of Exhaust Air Water FKW SWS m 3 /h m 3 /h DGE-TGW DGE-TGW DGE-TGW DGE-TGW The given measurements are based on the standard model. Other models can be produced upon request. The table gas washer is manufactured on a moveable table. Model markings for the TGW model of DGE-laboratory gas washers DGE GmbH Table Gas Washer Size Material Year of Manufacture DGE-table gas washers are selfproduced. Our complete line of column accessories includes distributor floors, nozzles ph measuring lines measuring containers drip-separators All accessories can be delivered upon request. For special exhaust air decontamination applications, DGE provides its own decontamination methods, years of know-how and extensive references. DGE TGW A B C DGE-table gas washer are designed for the separation of dust particles, solid particles and aerosol in combination with absorption or chemsorption. If necessary, the DGE-table gas washers can be outfitted with lye acid measuring stations. Our measuring and analysis units can be integrated into your system in order to track the separation activity. The measurements are recorded as readable files. As a provider of system solutions, we are happy to consult with you and to work together with you to provide the systems concept best suited to your particular need. We help optimize resource consumption and lower waste disposal costs. In doing so, we always try to find the best existing possibilities for running processes with a maximum recycling of materials. For particularly sensitive systems, we offer our customers a mobile service guarantee and the guarantee that repairs will be made within 24 hours. DGE GmbH Hufelandstraße Wittenberg Tel.: +49-(0) Fax: +49-(0) DGE-INFO@t-online.de Internet: