1、 Reference number ISO 9912-1:2004(E) ISO 2004INTERNATIONAL STANDARD ISO 9912-1 First edition 2004-10-01 Agricultural irrigation equipment Filters for micro-irrigation Part 1: Terms, definitions and classification Matriel agricole dirrigation Filtres pour micro-irrigation Partie 1: Termes, dfinitions
2、 et classification ISO 9912-1:2004(E) PDF disclaimer This PDF file may contain embedded typefaces. In accordance with Adobes licensing policy, this file may be printed or viewed but shall not be edited unless the typefaces which are embedded are licensed to and installed on the computer performing t
3、he editing. In downloading this file, parties accept therein the responsibility of not infringing Adobes licensing policy. The ISO Central Secretariat accepts no liability in this area. Adobe is a trademark of Adobe Systems Incorporated. Details of the software products used to create this PDF file
4、can be found in the General Info relative to the file; the PDF-creation parameters were optimized for printing. Every care has been taken to ensure that the file is suitable for use by ISO member bodies. In the unlikely event that a problem relating to it is found, please inform the Central Secretar
5、iat at the address given below. ISO 2004 All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from either ISO at the addres
6、s below or ISOs member body in the country of the requester. ISO copyright office Case postale 56 CH-1211 Geneva 20 Tel. + 41 22 749 01 11 Fax + 41 22 749 09 47 E-mail copyrightiso.org Web www.iso.org Published in Switzerland ii ISO 2004 All rights reservedISO 9912-1:2004(E) ISO 2004 All rights rese
7、rved iiiForeword ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Each member body interested in a subject for w
8、hich a technical committee has been established has the right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all
9、 matters of electrotechnical standardization. International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2. The main task of technical committees is to prepare International Standards. Draft International Standards adopted by the technical committees are c
10、irculated to the member bodies for voting. Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. ISO shall not be held resp
11、onsible for identifying any or all such patent rights. ISO 9912-1 was prepared by Technical Committee ISO/TC 23, Tractors and machinery for agriculture and forestry, Subcommittee SC 18, Irrigation and drainage equipment and systems. ISO 9912 consists of the following parts, under the general title A
12、gricultural irrigation equipment Filters for micro-irrigation: Part 1:Terms, definitions and classification Part 2: Strainer-type filters Part 3: Automatic self-cleaning strainer-type filters ISO 9912-1:2004(E) iv ISO 2004 All rights reservedIntroduction Clogging of irrigation system components and,
13、 in particular, of drip emitters, is one of the main problems encountered in micro-irrigation. Materials causing clogging include debris, suspended particles of organic and inorganic origin (sand, silt, clay, plastics, algae and water-borne insects), chemical deposits (calcium carbonate and magnesiu
14、m carbonate, calcium sulphate, metal oxides and metal hydroxides) and biological suspensions (slime secretions and fibres). Severe clogging problems are often the result of a combination of a number of these. The effect of the clogging materials differs according to the water source (see Annex A for
15、 a list of irrigation water sources). With surface water supplies, water quality may also vary from one season to another and with chemical injection. In addition, clogging hazards depend on the operating conditions, pumping regime, irrigation system and chemical injection program. The function of t
16、he filter in an irrigation system is to remove materials from the water that can clog or otherwise foul the various components of the system. However, under typical irrigation conditions, and in view of the wide range of size and hardness of suspended particles in irrigation water, complete removal
17、of all suspended particles cannot be expected. Moreover, under conditions of alkaline or hard water when accompanied by conditions of high biological activity and/or high suspended organic particle content, the materials passing through the filter are liable to coalesce in the piping system and/or i
18、n the emitters and to cause clogging. Hence, depending on the water quality, it could be necessary to use two or more filters in series in different parts of the system to minimize clogging. Under conditions of problematic water and high filtration efficiency, clogging of the filters themselves may
19、prove to be the main problem and completion of an irrigation set may be impeded due to the need for their frequent cleaning. Various operating methods, using either absorption or separation, are employed in order to separate and/or remove clogging materials from irrigation water. In turn, separation
20、 can be by means of surface separation (gravity surface separation, pressurized surface separation or self-circulating separation), centrifugal separation, entrapment or interception. INTERNATIONAL STANDARD ISO 9912-1:2004(E) ISO 2004 All rights reserved 1Agricultural irrigation equipment Filters fo
21、r micro-irrigation Part 1: Terms, definitions and classification 1 Scope This part of ISO 9912 defines terms used in relation to filters intended for agricultural micro-irrigation systems in particular, pressurized systems and provides a means of classifying those filters according to filtration met
22、hod, structure, operating principle and function. It does not deal with classification according to the type of water intended to be filtered; nor does it apply to the classification of filters for potable or domestic water use. 2 Terms and definitions For the purposes of this document, the followin
23、g terms and definitions apply. 2.1 filtration process employing a permeable medium and/or spinning component to separate, from water, materials that would clog an irrigation system, also employing a means for removing those materials from the permeable medium or spinning component such that the capa
24、city of the medium or component to separate the materials is renewed 2.2 pre-filtration process for separating primarily large particles from water to be filtered with the object of reducing the clogging of the filter elements and, consequently, the head loss across the filter elements 2.3 intercept
25、ion method of removing suspended particles from water, by gravity, employing gravel partitions between reservoir basins to separate the suspended particles from the water 2.4 surface separation method of unpressurized separation that depends on gravity and employs an inclined separating element, suc
26、h as a screen, mesh or strainer, to separate suspended particles and larger clogging material from the water 2.5 centrifugal separation method of separation that separates, from water, clogging material heavier than water and that employs a spinning technique using centrifugal forces exerted by the
27、filtered water, as in a hydrocyclone ISO 9912-1:2004(E) 2 ISO 2004 All rights reserved2.6 entrapment method of filtration in which clogging material is captured within the interior of a three-dimensional filter medium 2.7 self-circulating separation method of filtration that employs a screen, or any
28、 other suitable filter medium, and a spinning technique used with or without flow adjustment, for separating clogging materials from water 2.8 strainer-type filter strainer device containing one or more filter elements, such as a screen or mesh, used for separating clogging materials from water flow
29、ing through the device by collecting it on the surface of the filter element, or elements 2.9 filtrate debris, suspended particles of organic or inorganic origin, or other contaminants removed from water in the filtration process 2.10 flushing method of removing clogging material from a filter using
30、 water without removal of the filter element or, following removal of the element, by manually removing clogging material from the filter element using water 2.11 back flushing reverse flushing method of removing filtrates from a filter by passing filtered water through the filter medium or over the
31、 surface of the filter element, in a direction opposite to the normal flow of water, to remove accumulated, trapped or separated filtrates from the filter, without disassembling the filter 2.12 continuous flushing method of removing clogging material from a filter element by controlled continuous fl
32、ow of purge water 2.13 through flushing flushing by means of high-velocity, high-pressure flow through a discharge valve or outlet used for filters especially designed for this type of flushing 2.14 simultaneous back flushing flushing occurring simultaneously through all areas of the filter element
33、or through all the individual elements of a multi-element filter 2.15 sequential back flushing back flushing of one or more individual filter elements functioning in parallel after their removal from service for back flushing, frequently using filtered water from some or all of the remaining filter
34、elements 2.16 directed jet flushing flushing that employs a high-velocity stream of clean water directed at a portion of the area of a filter element on the downstream side of the filter, thus causing a localized reverse flow that flushes the filtrate from a portion of the filter element, and which
35、then moves over the entire area of the element to progressively back flush all of it ISO 9912-1:2004(E) ISO 2004 All rights reserved 32.17 disposable element filter filter that cannot be flushed or cleaned from which clogging material is removed when the filter element is replaced 2.18 automatic flu
36、shing filter filter in which both the initiation and the termination of discrete flushing cycles are activated automatically by different means (pressure drop, time, volume of water passing through the filter, etc.) 2.19 semi-automatic flushing filter filter in which the flushing sequence or cycle i
37、s manually activated, followed by automatic termination of flushing, generally by means of time or volume of flushing water 2.20 manual flushing filter filter constructed so that manual opening of a valve causes a discharge appropriately oriented and of sufficient volume and velocity to flush the fi
38、lter without disassembly 2.21 manually cleaned filter filter that must be disassembled and manually washed using water to remove filtrates from the filter element 2.22 disc filter filter in which the filter element is composed of discs with grooved or textured surfaces arranged one on top of the oth
39、er to form a stack, creating a porous space between adjacent discs within which the filtrate is trapped or deposited 2.23 cartridge filter filter using a media filter element held together as a single replaceable component of the filter for cleaning purposes 2.24 filter element component or assembly
40、 that embodies or holds together the filter medium or surface separation device that removes the filtrates from water by entrapment or separation 2.25 strainer filter element component of a strainer-type filter consisting of a perforated plate, screen, mesh, or a combination of these, intended to re
41、tain clogging materials larger than a specified size from the water flowing through the component 2.26 media filter element depth filter element component, housing or assembly containing a three-dimensional filter medium such as sand, gravel, textile, fibres or a porous mass of bonded particles, emp
42、loying entrapment as a method of filtration 2.27 filter medium porous permeable material employed in filtration within which the filtrate is trapped or deposited 2.28 pressurized filter filter designed for operation with an inlet pressure greater than atmospheric pressure ISO 9912-1:2004(E) 4 ISO 20
43、04 All rights reserved2.29 gravity filter filter that does not employ pressure or a vacuum to produce a high differential pressure but in which the driving force for filtration is provided solely by the elevation of the free surface of water contained in the filter above the filter medium 2.30 vacuu
44、m filter filter designed for operation in which the discharge side of the filter is below atmospheric pressure, as on the suction side of a pump 2.31 hydrocyclone device in which clogging material is separated from water by a centrifugal force resulting from rotation of the water, generally by intro
45、ducing the water so that it flows in a tight vortex and the clogging material is thrown to the walls, causing the bulk of the water to exit from the chamber at the centre of the vortex and the clogging material and the rest of the water to exit from the chamber through its apex or bottom 2.32 in-lin
46、e filter co-axial filter filter for which the inlet and the outlet are coaxial 2.33 on-line filter non-coaxial filter filter in which the inlet and the outlet are not coaxial 2.34 filter housing component of a filter that houses or supports the filter medium 2.35 media filter depth filter filter in
47、which clogging material is trapped within the interior of a three-dimensional filter medium, such as sand, gravel, textile, fibres or a porous mass of bonded particles 2.36 sand filter media filter in which the filter medium consists of sand, gravel or other natural or synthetic particles, in some c
48、ases employing layers of the filter medium, each of a different particle size 2.37 nominal flow rate of filtration flow rate through a filter for proper filtration, as declared by the manufacturer ISO 9912-1:2004(E) ISO 2004 All rights reserved 53 Classification 3.1 General Filtration devices for ir
49、rigation water shall be classified under the following major categories and according to any particular characteristic(s) the device possesses, as specified in 3.2 to 3.11. The intention is to cover all possibilities for different types of devices by classifying them according to filtration method, configuration and filter medium, system used to remove filtrates from the filter, method used to achieve flushing of the filter, pressure requirements for operation of the filter, velocity of filtration, filter structure
