Title of Invention

A LIQUID FILTRATION SYSTEM FOR FILTERING LIQUID

Abstract

A liquid filtration system for filtering liquid such as industrial liquids, machine coolants, agricultural solutions having particles in suspension comprising A) A dirty liquid tank; B) A strainer filter bag; C) A mineral bed filter vessel; D) A valve unit constructed & arranged to fluidly connect the dirty liquid tank, process inlet, strainer filter bag with each other & with the filter vessel, the valve unit facilitating filtering cycle, back washing cycle & rinse cycle and having means to differently connect A, B and C mentioned above in respective phases such as : i) Facilitating dirty liquid to flow from dirty liquid tank to filter and further to process inlet with or without booster pump in filtration phase; ii) Facilitating dirty liquid to flow from dirty liquid tank to filter in reverse direction of filter cycle to remove clogged dirt to flow to strainer filter bag in backwash phase; iii)Dirty liquid to flow from dirty liquid tank to filter in filtration direction in rinse cycle however connecting the rinsed liquid to strainer filter bag.

Full Text

FORM -2 THE PATENTS ACT, 1970 (39 of 1970) COMPLETE Specification SECTION -10 A LIQUID FILTRATION SYSTEM FOR FILTERING LIQUID MILIND MADHAV VAIDYA, of Plot No.5, Block No.6, Ashwini Apartment, Happy Colony, Kothrud, Pune 411029, Maharashtra, India, an Indian National THE FOLLOWINGSPECIFICATIONPARTICULARLYDESCRIBES THE NATURE OF THIS INVENTION AND THE MANNER IN WHICH IT IS TO BE PERFORMED:- This invention relates to a liquid filtration system, more particularly lo a liquid separation having undissolved solids, typically in suspension. UK Patent GB 2252058 DT. 25.1.1991.[no Indian eqivalent] described a filter cleaning system particularly for Electro erosion liquid is consisting of a) Dirty liquid receptacle. b) Clean liquid receptacle. c) Setting tank receptacle divided into a first tank & second tank by means of a wall. Water hammer effect in the filter is encountered. This invention simplifies the filtration system by using just one dirty water receptacle while not compromising on the quality of filtration. The invention uses a simple removable strainer filter bag, which can be removed & washed periodically, eliminates expensive settling tank & avoiding no. of valves draining the decanted liquid & level switches etc. Further it reduces size of dirty liquid receptacle, as the liquid during backwash cycle is continuously percolating through a fine mesh (20 - 50 micron) strainer filter bag. Clean liquid receptacle is also eliminated by connecting filtered liquid to the end use in the process by using proper controls, through a booster pump . Using a valve immediately after pump eliminates water hammer effect. According to this invention there is provided a liquid filtration system for filtering liquid such as industrial liquids, machine coolants, agricultural solutions having particles in suspension comprising A) A dirty liquid tank; B) A strainer filter bag; C) A mineral bed filter vessel; D) A valve unit constructed & arranged to fluidly connect the dirty liquid tank, process inlet, strainer filter bag with each other & with the filter vessel, the valve unit facilitating filtering cycle, back washing cycle & rinse cycle and having means to differently connect A, B and C mentioned above in respective phases such as : i)Facilitating dirty liquid to flow from dirty liquid tank to filter and further to process inlet with or without booster pump in filtration phase; ii)Faciliating dirty liquid to flow from dirty liquid tank to filter in reverse direction of filter cycle to remove clogged dirt to flow to strainer filter bag in backwash phase; iii)Dirty liquid to flow from dirty liquid tank to filter in filtration direction in rinse cycle however connecting the rinsed liquid to strainer filter bag. Typically the strainer filter bag is kept at an elevation above dirty liquid tank to allow percolation of liquid during backwash and rinse while trapping the dirt in the form of sludge. Typically at least one pump in order to supply dirty liquid to mineral bed filter and regulate the flow in the system. Typically a fork is provided in the clean liquid pipe (17) to permit flow to dirty liquid tank. The invention will now be described with reference to the accompanying drawings in which Figure 1 shows a Single Tank Manual Mode System for filtering liquids in accordance with this invention; Figure 2 shows the Backwash with Air or Gas details for the system of Figure 1. Ref.Fig. 1. Industrial dirty process liquid 35 is filtered as it flows from inlet 32 to outlet 33 of mineral bed filter 13 via minerals 14. When the flow through reduces below expected flow rate it implies clogging of minerals 14 with dirt from process liquid. Then valve 7 is adjusted to reverse the flow, through the filter, the backwash dirty liquid flows to strainer filter bag 27, via pipe 26. Then forward flow is restored to rinse the filter, liquid still flowing from filter to strainer filter bag 27. Finally normal filtration is restored which however initially delivers slightly soiled water, which is avoided to go to process by either using valve 4, which is initially closed & opened slowly to full opening within 30 secs or by keeping valve 19, initially closed & keeping valve 31 opened for 20 secs, then valve 19 is opened & 31 is closed. The strainer filter bag 27, collects filter backwash dust of process & allows the liquid to filter backwash liquid back to dirty liquid receiver 1, which is also receiving liquid from the process. B. Auto Mode In general the system in Auto mode is as depicted in fig. 1. However, operation of valve 7, valve 4 or valve 31/valve 19 is to be actuated either electrically or pneumatically or hydraulically based on sensing done by pressure switch 37 mounted on filter vessel 13 & timers 38 & 39 coupled to valve 7 for backwash and rinse cycle periods. The system can be further automated by PLC control or computer of the process equipment. C. Filtered liquid through pipe 17, in filtration cycle, can be connected to pump 20 through valve 19 & thus boosted pressure liquid (if desired) can be supplied to process via valve 21 through pipe 22 & 23 or to various user points through fork 34, as may be desired. D. Filtration Cycle The dirty liquid 35 pumped by pump 3 via isolation valve 2 & 4 & non return valve 5 (optional) through pipe 6 to valve 7 through port 8. Port 8 and port 9 are connected with each other during filtration cycle. The liquid from valve port 9 is connected to filter 13 inlet part 32. The filter 13 is having pressure gauge 15 & pressure switch 37 (in case of automode) & vent valve 16, allows the dirty liquid to pass through mineral bed 14 and clean filtered liquid flows out through port 33 via valve ports 10 & 11 through pipe 17, to process. E. Backwash Cycle The dirty liquid 35, pumped by pump 3 via isolation valve 2 & 4 & non return valve 5 (optional) through pipe 6 to valve 7 through port 8 which inturn in connected to port 10, which enters the filter through 33 & cleans the dirt load stuck in mineral bed 14 & flows out via filter port 32 through valve 7 via pipe 26 to strainer filter bag 27. F. Rinse Cycle The dirty liquid 35, pumped by pump 3 via isolation valve 2 & 4 & non return valve 5 (optional) through pipe 6 to valve 7 through port 8 to port 9. The liquid from valve port 9 is connected to filter 13 as in filtration cycle. The liquid flows from port 33 through port 10 & 12 via pipe 26 to strainer filter bag 27, mounted on steel structure 28 above the dirty liquid tank 1. G. Restoring Filter Cycle Close valve 4, start pump 3, slowly open valve 4, in 30 sec. to avoid slightly soiled liquid going back to process. Follow filtration cycle as described earlier. H. Backwash with Air or Gas - Ref. Fig. 2 To aid backwash especially in case of viscous liquids with sticky sludge e.g. in straight cutting oil, air or gas can be connected to filter 13 through valve 41 via fork 40 or through valve 42 at the bottom of filter 13 or through valve 43, just above the mineral bed 14, to filter 13. I CLAIM 1. A liquid filtration system for filtering liquid such as industrial liquids, machine coolants, agricultural solutions having particles in suspension comprising A) A dirty liquid tank; B) A strainer filter bag; C) A mineral bed filter vessel; D) A valve unit constructed & arranged to flu idly connect the dirty liquid tank, process inlet, strainer filter bag with each other & with the filter vessel, the valve unit facilitating filtering cycle, back washing cycle & rinse cycle and having means to differently connect A, B and C mentioned above in respective phases such as : i)Facilitating dirty liquid to flow from dirty liquid tank to filter and further to process inlet with or without booster pump in filtration phase; ii)Facilitating dirty liquid to flow from dirty liquid tank to filter in reverse direction of filter cycle to remove clogged dirt to flow to strainer filter bag in backwash phase; iii)Dirty liquid to flow from dirty liquid tank to filter in filtration direction in rinse cycle however connecting the rinsed liquid to strainer filter bag. 2. A liquid filtration system for filtering liquid as claimed in claim 1 in which, which includes a booster pump for pumping filtered liquid to process work station or stations. 3. A liquid filtration system for filtering liquid as claimed in any one of the preceding claims, in which the strainer filter bag is kept at an elevation above 7 dirty liquid tank to allow percolation of liauid during backwash and rinse while trapping the dirt in the form of sludge. 4. A liquid filtration system for filtering liquid as claimed in any one of the preceding claims, which includes at least one pump in order to supply dirty liquid to mineral bed filter and regulate the flow in the system. 5. A liquid filtration system for filtering liquid as claimed in any one of the preceding claims, in which a fork (18) is provided in the clean liquid pipe (17) to permit flow to dirty liquid tank. 6. A liquid filtration system for filtering liquid as claimed in any one of the preceding claims, in which a backwash phase is provided with gas having connection via fork at outlet of filter a) via fork at drain of filter b) connection above the mineral bed surface. 7. A liquid filtration system for filtering liquid as described with reference to accompanying drawings fig. 1 and fig. 2. Dated this 1stday of June 2000 Dr. Mohan Dewan Of R. K. Dewan & Co Applicant's Patent Attorney

Documents:

514-mum-2000-abstract(21-07-2003).doc

514-mum-2000-abstract(21-07-2003).pdf

514-mum-2000-cancelled pages(21-07-2003).pdf

514-mum-2000-claims(granted-(21-07-2003).doc

514-mum-2000-claims(granted-(21-07-2003).pdf

514-mum-2000-correspondence(09-06-2004).pdf

514-mum-2000-correspondence(ipo)-(08-10-2004).pdf

514-mum-2000-drawing(21-07-2003).pdf

514-mum-2000-form 1(02-06-2000).pdf

514-mum-2000-form 19(20-05-2003).pdf

514-mum-2000-form 2(granted-(21-07-2003).doc

514-mum-2000-form 2(granted-(21-07-2003).pdf

514-mum-2000-form 3(14-08-2001).pdf

514-mum-2000-power of attorney(02-06-2000).pdf

abstract1.jpg