1、Grease separators Part 2: Selection of nominal size, installation, operation and maint enance The European Standard EN 1825-2:2002 has the status of a British Standard ICs 13.060.99 BS EN 1825-212002 BS EN 1825-212002 Amd. No. National foreword Date Comments This British Standard, having been prepar
2、ed under the direction of the Building and Civil Engineering Sector Policy and Strategy Committee, was published under the authority of the Standards Policy and Strategy Committee on 29 March 2002 This British Standard is the official English language version of The UKparticipation in its preparatio
3、n was entrusted to Technical Committee B/505, Wastewater engineering, which has the responsibility to: EN 1825-212002. - - aid enquirers to understand the text; present to the responsible European committee any enquiries on the interpretation, or proposals for change, and keep the UK interests infor
4、med; monitor related international and European developments and promulgate them in the UK. - A list of organizations represented on this committee can be obtained on request to its secretary. Cr oss-r e fer enc e s The British Standards which implement international or European publications referre
5、d to in this document may be found in the BSI Standards Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Find” facility of the BSI Standards Electronic Catalogue. A British Standard does not purport to include all the necessary provisions of a con
6、tract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Summary of pages This document comprises a front cover, an inside front cover, the EN title page, pages 2 to 27 and a back co
7、ver. The BSI copyright date displayed in this document indicates when the document was last issued. O BSI 29 March 2002 ISBNO58038215X EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 18252 February 2002 ICs 13.060.30 English version Grease separators - Part 2: Selection of nominal size, i nstal
8、 la t io n , operation and ma i n tenance Installations de sparation de graisses - Partie 2: Choix des tailles nominales, installation, service et entretien Abscheideranlagen fr Fette - Teil 2: Wahl der Nenngre, Einbau, Betrieb und Wartung This European Standard was approved by CEN on 29 September 2
9、001 CEN members are bound to comply with the CENKENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained o
10、n application to the Management Centre or to any CEN member. This European Standard exists in three official versions (English, French, German). A version in any other language made by translation under the responsibility of a CEN member into its own language and notified to the Management Centre ha
11、s the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Malta, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom. EUROPEAN
12、 COMMITTEE FOR STANDARDIZATION EUROPISCHES KOMITEE FR NORMUNG COMIT EUROPEN DE NORMALISATION Management Centre: rue de Stassart, 36 B-1050 Brussels O 2002 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 1825-2:2002 E EN 1825-212002
13、 (E) Contents page Foreword 3 1 2 3 4 5 6 6.1 6.2 6.2.1 6.2.2 6.2.3 6.2.4 6.3 6.4 7 7.1 7.2 7.3 7.4 8 Scope 3 Normative references 3 Terms and definitions 3 Ap pl cat ion 4 Nominal size . 5 Selection of the nominal size 5 General 5 Determination of the specific values . 5 Maximum flow rate of wastew
14、ater 5 Temperature factor 4 . 6 Density factor fd . 6 Detergent and rinsing agent factor fr 7 Special cases 7 Determination of sludge trap volume 7 Installation 8 Limitations 8 Place of installation . 8 Drainage to and from the separator . 8 Ventilation . 8 Operation, inspection and maintenance . 9
15、Annex A (normative) Calculation of maximum wastewater flow Os . 10 A.l Calculation based on equipmentlfittings discharging into the separator . 10 A.l . 1 General 10 A.1.2 A.2 Method based upon the type of establishment discharging into the separator . 11 A.2.1 General I1 A.2.2 Maximum wastewater fl
16、ow rate Qs 11 Annex B (informative) Densities of greases and oils 14 Annex C (informative) Examples of determining nominal size of grease separator . 16 C.l Examples of calculation based on equipmentlfittings discharging into the separator 16 C.2 Annex D (informative) Measures to prevent grease accu
17、mulating and grease build-up in the pipelines Bibliography 27 Maximum wastewater flow rate Qs 10 Examples of calculation based on the type of establishment discharging into the separator . 21 upstream of the grease separator 26 2 EN 1825-212002 (E) Foreword This document EN 1825-2:2002 has been prep
18、ared by Technical Committee CEN/TC 165 “Wastewater engineering“, the secretariat of which is held by DIN. This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by August 2002, and conflicting national stan
19、dards shall be withdrawn at the latest by June 2004. When pollution control requires the treatment of pollutants other than light liquids, additional measures might be necessary. It is the second part of a two part standard for grease separators. Part 1 gives principles of design, performance and te
20、sting, marking and quality control of grease separators. Annex A is normative. The annexes B, C and D are informative. According to the CENKENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Cz
21、ech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Italy, Ireland, Luxembourg, Malta, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and the United Kingdom. 1 Scope This European Standard provides guidance on the selection of nominal sizes, installation, operation and maint
22、en- ance of grease separators manufactured in accordance with prEN 1825-1. This standard does not apply to wastewater containing light liquids, e.g. grease or oils of mineral origin, and does not include treating stable emulsions of grease or oil in water. The standard does not cover the use of biol
23、ogical additives (bacteria, enzymes). 2 Normative references This European Standard incorporates by dated or undated references, provisions from other publications. These normative references are cited at the appropriate places in the text, and the publications are listed hereafter. For dated refere
24、nces, subsequent amendments to or revisions of any of these publications apply to this European Standard only when incorporated in it by amendment or revision. For undated references the latest edition of the publication referred to applies (including amendments). prEN 1825-1 :2000, Grease separator
25、s - Part I: Principles of design, performance and testing, marking and quality control. EN 12056-2, Gravity drainage systems inside buildings - Part 2: Sanitary pipework, layout and calculation. 3 Terms and definitions For the purposes of this European Standard the terms and definitions given in prE
26、N 1825-1 and EN 12056-2 and the following apply. 3 EN 1825-212002 (E) 3.1 selection of the nominal size determination of the appropriate nominal size of the grease separation chamber for a specific case, based on amount and type of influent 4 Application Grease separators shall be used wherever it i
27、s necessary to separate greases and oils of vegetable and animal origin from wastewater, such as in trade or industrial plants/establishments, e.g. commercial kitchens and large catering establishments, e.g. in inns, hotels, motorways service stations, canteens; grilling, roasting and frying facilit
28、ies; food distribution points (with returnable crockery); butchers shops, with or without slaughtering facilities; meat and sausage factories, with or without slaughtering facilities; a battoirs; poultry slaughterers; tripe preparation plants; animal rendering plants; bone and glue boiling plants; s
29、oap and Stearine factories; oil mills; vegetable oil refineries; margarine factories; pickling plants; fast-food preparation plants; chip and crisp producers; peanut roasting plants. Wastewater containing a considerable proportion of grease in a non-separable form (.e. emulsified) from applications
30、such as dairy, cheese making and fish processing, or from distribution points having only dish washing facilities, or from “wet waste compactors”, will only be effectively treated in grease separators under certain conditions. The wastewater may require further treatment. Applications where the disc
31、harged wastewater contains solids that are quick to purify (e.g. the fish industry) do not require a sludge trap, but the grease separator shall be fitted with a strainer or screening device fitted on the inlet side to retain coarse solids. Any retained solids should be removed and the separator tho
32、roughly flushed with clean water before operational intervals to prevent putrefaction. 4 EN 1825-212002 (E) 5 Nominal size For the preferred nominal sizes (NS) see clause 4 of prEN 1825-1:2000. Multiple separators of the same nominal size may be connected in parallel with the flow split equally betw
33、een each separator. 6 Selection of the nominal size 6.1 General The selection of the nominal sizes shall be based on the nature and quantity of wastewater to be treated taking into account: - maximum flow rate of wastewater; - maximum temperature of the wastewater; - density of grease/oils to be sep
34、arated; - influence of cleansing and rinsing agents. If a grease storage capacity greater than 40 . NS in litres is required, e.g. when more than the usual amount of grease is expected, the following options may be used: 1) 2) using a larger nominal size separator than calculated or creating grease
35、storage capacity outside the separator or 3) emptying the separator more frequently than usually. Where no specific sizing method is offered by a regulatory authority, then the nominal size of the separator shall be determined from the following formula: NS = Qsf;fdf, (1) where NS is the calculated
36、nominal size of the separator; Qs is the maximum flow rate of wastewater, entering the separator in litres per second; 4 is the impedient factor for the temperature of influent; is the density factor for the relevant grease/oil; fr is the impedient factor for the influence of cleansing and rinsing a
37、gents. After calculation select the next higher preferred nominal size in accordance with clause 4 of prEN 1825-1:2000. 6.2 Determination of the specific values 6.2.1 Maximum flow rate of wastewater The maximum flow rate of wastewater Qs shall be determined by: 5 EN 1825-212002 (E) Temperature of wa
38、stewater at inlet “C I60 always or occasionally 60 a) measurement, or b) calculation based upon catering equipment discharging into the grease separator, or Temperature factor ft 1 ,o 1,3 c) calculation based upon the type of establishment discharging into the grease separator, or d) special calcula
39、tion for individual cases, if acceptable by the regulatory authority. Where data is available to determine Qs by b) or c), and the designer is unsure of the most appropriate option of use, it is recommended that the higher of the flow rates determined from both calculations is used. 6.2.2 Temperatur
40、e factor 4 High wastewater temperature reduces the efficiency of grease separators. Temperature factors 4 are given in Table 1. Table 1 -Temperature factor 4 6.2.3 Density factor fd A density factor fd = 1,0 shall be used for wastewater discharged from kitchens, abattoirs and meat and fish processin
41、g plants. When the nature of grease/oil is well known, the density coefficient may be taken from Figure 1, where fd is plotted for a range of different grease and oil densities. For grease/oil densities 0,94 g/cm3, a density factor of 13 shall be used. Densities of different fats and oils are given
42、in annex B. 6 EN 1825-212002 (E) Use of detergent and rinsing agents Never used Occasionally or always used Special cases, e.g. hospitals o 0,85 0.90 g/cm3 0,95 Detergent and rinsing agent coefficient fr 1 ,o 13 2 1,5 Figure 1 - Relation between fd and density 6.2.4 Detergent and rinsing agent facto
43、r fr Detergents, including dishwasher powders and rinsing agents, should carefully be selected and used sparingly. They shall not impair the separating effect as far as possible and not form stable emulsions where they are used upstream of a separator. A detergent and rinsing agent coefficient shall
44、 be chosen from Table 2. National and local regulations may limit the use of certain detergents, rinsing agents and solvents. 6.3 Special cases For industrial plants such as abattoirs and wholesale butchers, the grease separator nominal size NS should be selected on the basis of site specific invest
45、igation. 6.4 Determination of sludge trap volume The sludge trap volume shall be at least 100 . NS in litres but for abattoirs and similar plants a volume of at least 200 . NS in litres is recommended. 7 EN 1825-212002 (E) 7 Installation 7.1 Limitations Only wastewater containing organic grease and
46、oils shall be discharged to a grease separator. In particular, the following shall not be discharged to a grease separator: - wastewater containing faeces (“black“ water); - rainwater; - wastewater containing light liquids, e.g. grease or oil of mineral origin. 7.2 Place of installation Grease separ
47、ators should be installed close to the sources of wastewater but should not be sited in unventilated rooms, roads, car parks or storage areas. To prevent odour and fly nuisance, separators should not be sited close to habitable buildings, especially to opening windows and air intakes. They shall be
48、easily accessible to cleaning vehicles. Specific operational and structural conditions may require the separator to be remotely located from the source of wastewater. Separators should be installed in such a way to prevent frost damage, and allow all parts requiring regular maintenance to be easily
49、accessible at all times. Where necessary, manhole covers on separators shall be supported so that the load imposed on the separator does not exceed its design strength. 7.3 Drainage to and from the separator Where no specific local regulations exist, grease separators shall be connected to the drains and sewers as follows: The wastewater to the grease separator shall be gravity fed. If the static water level in the grease separator is lower than the flood level (see EN 752-I), then the effluent from the separator shall be discharged to the drainage system using a wastewater liftin
