CROSS-REFERENCES TO RELATED APPLICATIONS
[0001] This application is a complete specification of and claims priority to provisional patent application 3387/CHE/2015 entitled “APPARATUS FOR WASHING MACHINE RINSE WATER TREATMENT AND REUSE” filed on July 2, 2015.
Field of the Invention
[0002] The present invention relates to an apparatus for washing machine rinse water treatment, and in particular to apparatus and system for treating wash and rinse water for reuse, cost effectively and efficiently.
Description of the Related Art
[0003] Water is a valuable resource, which is under constant threat due to climate change and resulting drought, explosive population growth and indiscriminate waste disposal. Current and future demand for fresh water can be only met by enhancing water use efficiency and demand management. Domestic water consumption makes up to 8% of total global water use. Domestic wastewater is generated from bathrooms, kitchens, laundries and toilets. Thus, a large potential exists for reducing the demand for freshwater for domestic use. One of the ways to reduce the impact of water scarcity and pollution is to expand onsite water and wastewater reuse at homes.
[0004] Washing machine is a very common facility used in most households. Each washing consumes up to 120 L of water. By treating and reusing the wastewater from washing machine, one can reduce water demand within a household by 30 - 80%. Hence, there is a need to develop an in situ treatment system for the reuse of wastewater generated from the washing machine. Such a system should have the capability of adapting to the existing features of the washing machine and synchronising with the time schedule of the washing machine. It should be easy to operate, economical and socially acceptable. The water quality standards for wastewater recycling depend on location and application. The most stringent criteria require turbidity to be below 5 NTU and a non-detectable level of either total or fecal coliforms (USEPA, 2004).
[0005] A number of technologies have been used for wash water recycling. They range from simple 2-stage processes of coarse filtration and disinfection, to physical,

physicochemical and biological processes (Jefferson et al., 2000). The biological process technologies, though widely used in large buildings (Surendran and Wheatley, 1998; Nolde, 1999; Friedler, 2004) suffer from problems arising due to feed source variability and potential shock loading at smaller scale. Problems of shock loads and variability in incoming water quality can be addressed to a certain extent by using simple physical processes such as cartridge filters or depth filtration beds. Though these technologies are effective in removing the turbidity and suspended matter from wash water, they do not improve the chemical and biological quality significantly (Jefferson et al., 2000).
[0006] The current practice in many urban and peri-urban households is draining of wash water from washing machines to the drains along with other wastewaters generated in the household, including toilets. A few studies have reported that a storage reservoir is placed at the sides of the washing machine, so that the third rinse water is reused as first rinse water in the subsequent operation (Mertz et al., 1994).
[0007] Therefore, there is a need to develop an apparatus to treat and utilize the wash water as rinse water in the entire cycle of washing operation, with fully automated control system, so that it is possible to reduce the use of potable water in a household. The present disclosure addresses the treatment of wash or rinse water from the washing machine cost effectively and efficiently with fully automated control system for reuse. The treatment scheme includes chemical treatment such as coagulation, flocculation, and disinfection followed by micro filtration, with the help of a fully automated control system, with further related advantages as set forth here.

SUMMARY OF THE INVENTION
[0008] A washing machine for clothes configured to reuse water and integrated with a rinse water treatment apparatus, comprising a washing machine, a storage tank provided with an agitator, a control system, and a water inlet fitted with an inlet valve configured to allow wash or rinse water from the washing machine into the storage tank. In one embodiment, the apparatus further includes a water outlet connected to a pump configured to pump water from the storage tank to the washing machine, a drain, a treatment module configured to store and inject one or more of a flocculating agent, a coagulating agent or a disinfecting agent into the storage tank, and one or more automated level sensors configured to assess level of water in the storage tank.
[0009] In one embodiment, the control system is configured to control the operations of allowing wash or rinse water from the washing machine into the storage tank or to the drain based on inputs from the control system. In one embodiment, the control system is configured to control the operations of treating wash or rinse water in the storage tank by causing the treatment module to inject one or more of the flocculating agent, the coagulating agent or the disinfecting agent into the storage tank to produce treated water. In one embodiment, the control system is configured to control the operations of allowing treated water via the water outlet or fresh water from a supply line into the washing machine based on the level of treated water.
[0010] In one embodiment, the apparatus further comprising a water quality sensor affixed to the water inlet to assess quality of the wash or rinse water. In one embodiment, the apparatus further comprising a water quality sensor affixed to the storage to assess quality of the treated water.
[0011] In one embodiment, the apparatus further comprising a 3-way valve configured to either allow water into the storage tank or to bypass from the water inlet to the drain based on inputs from the water quality sensor affixed to the inlet, or the level sensors, or both. In one embodiment, the 3-way valve is configured to allow water into the drain via bypass if the water quality sensor affixed to the water inlet detects the quality to be below a threshold value, or if the water level in the storage tank is above a threshold value.

[0012] In one embodiment, the treating further comprises injecting the flocculating agent, the coagulating agent or the disinfecting agent in a predetermined cycle. In one embodiment, the flocculating agent, the coagulating agent or the disinfecting agent are injected in a predetermined sequence and in quantities determined based on inputs from the water quality sensor affixed to the tank, or the level sensors, or both.
[0013] In one embodiment, the predetermined cycle further comprises agitator operation or hold time. In one embodiment, the flocculating agent is one of aluminium sulphate, calcium oxide, polyacrylamide or sodium silicate. In one embodiment, the coagulating agent is one of alum, aluminium chloride, calcium hypochlorite, ferric chloride or ferric sulphate. In one embodiment, the disinfecting agent is one of chlorine, chlorine dioxide, hypochlorite or ozone.
[0014] In one embodiment, the apparatus further comprises a 3-way valve configured to either allow treated water from the water outlet or fresh water from the supply line to the washing machine. In one embodiment, the control system is configurable to manual selection of treatment of rinse water, wash water or both. In one embodiment, the treatment of rinse or wash water is selected automatically based on inputs from the water quality sensor. In one embodiment, the control system is further configured to drain the storage tank when the level of treated water falls below a threshold.
[0015] In one embodiment, the water quality sensor is a conductivity sensor. In some embodiments, the level sensor is a mechanical float sensor, magnetic, capacitance, optical or microwave sensor. In one embodiment, the control system is configured to recognize water inlet demand, outlet demand or the status of the operational cycles of the washing machine. In one embodiment, the use of treated water or fresh water is based on inputs from the level sensor or the water quality sensor affixed to the tank, or status of the operational cycle. In one embodiment, the apparatus further comprising a software or hardware means for selecting between automatic and manual modes of operation.

BRIEF DESCRIPTION OF THE DRAWINGS
[0016] The invention has other advantages and features which will be more readily apparent from the following detailed description of the invention, when taken in conjunction with the accompanying drawings, in which:
[0017] FIG. 1 shows a block diagram of a washing machine configured to reuse water and integrated with a rinse water treatment system.
[0018] FIG. 2 shows a flowchart for treating wash or rinse water in the apparatus.
[0019] FIG. 3 shows a flowchart for the pre-defined operating sequence of the apparatus.
[0020] FIG. 4 is a flowchart for water in procedure call in the operating sequence of the apparatus.
[0021] FIG. 5 is a flowchart for water out procedure call in the operating sequence of the apparatus.
[0022] FIG. 6 is a schematic illustrating components of an apparatus for washing machine rinse water treatment.

DETAILED DESCRIPTION
[0023] While the invention has been disclosed with reference to certain embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted without departing from the scope of the invention. In addition, many modifications may be made to adapt to a particular situation or material to the teachings of the invention without departing from its scope.
[0024] Throughout the specification and claims, the following terms take the meanings explicitly associated herein unless the context clearly dictates otherwise. The meaning of "a", "an", and "the" include plural references. The meaning of "in" includes "in" and "on." Referring to the drawings, like numbers indicate like parts throughout the views. Additionally, a reference to the singular includes a reference to the plural unless otherwise stated or inconsistent with the disclosure herein.
[0025] The term “water in procedure call” refers to a demand raised by the control system to take the required quantity of fresh or recycled water through the water inlet valve. The term “water out procedure call” refers to a demand raised by the control system to pump-out used water to the drain or water recycling system through the water outlet valve.
[0026] In various embodiments, a washing machine for clothes configured to reuse water and integrated with a rinse water treatment system is disclosed. The rinse water treatment apparatus 100 for water recycling in the washing machine 110, as shown in FIG. 1, intended as an integral unit with the washing machine 110 and fully interfaced to recognize the operation cycle of the washing machine 110. In one embodiment, the apparatus 100 as shown schematically in FIG. 1 comprises a washing machine 110, a storage tank 101, a water inlet 102, a water outlet 103, a treatment module 104, a control system 105 and a drain 106.
[0027] In one embodiment, the storage tank 101 is provided with water inlet 102 and water outlet 103 for moving water from the washing machine 110 to the apparatus 100 and vice versa. In some embodiments, the storage tank 101 is provided with an agitator 107. The storage tank 101 is provided with a treatment module 104 for treating and storing treated water. In one embodiment, the apparatus 100 further includes a control system 105

for controlling the operational sequence of the apparatus 100 and washing machine 110. In various embodiments, the washing machine 110 is a standard washing machine equipped to wash clothes, with wash, soak, rinse and spin operational cycles. Controller 105 is configured to perform control functions of the washing machine including various types of wash programs, sensing of load, water level, operational cycle or state, etc. and in addition, perform various other control functions in conjunction with the water recycling system 100 as illustrated further herein.
[0028] In one embodiment, the water inlet 102 is fitted with an inlet valve 120 and water outlet 103 is connected to an outlet valve 130 via pump 140 and filter 141. In one embodiment, the inlet valve 120 is configured to allow wash or rinse water from a washing machine 110 into the storage tank 101. In one embodiment, the pump 140 is configured to pump water from the storage tank 101 to the washing machine 110. In one embodiment, the treatment module 104 is configured to store and inject one or more of a flocculating agent, a coagulating agent or a disinfecting agent into the storage tank 101. In one embodiment, the apparatus 100 further comprises a level sensor 150 to assess level of water in the storage tank 101.
[0029] In one embodiment, the apparatus 100 further comprising a water quality sensor 160 affixed to the water inlet 102 to assess quality of the wash or rinse water. In one embodiment, the apparatus 100 further comprises a water quality sensor 160 affixed to the storage tank to assess quality of the treated water. Additionally or optionally, a water quality sensor 161 could be affixed prior to the inlet valve 120 to determine whether to treat or drain the water from washing machine 110.
[0030] In one embodiment, the control system 105 is configured to control the operations of allowing wash or rinse water from the washing machine 110 into the storage tank 101 or to a drain 106 based on inputs from the sensors 150 and 160. In one embodiment, the control system 105 is configured to control the operations of treating wash or rinse water in the storage tank 101 by causing the treatment module to inject one or more of the flocculating agent, the coagulating agent or the disinfecting agent into the storage tank 101 to produce treated water. In one embodiment, the control system 105 is configured to

control the operations of allowing treated water via the water outlet 103 or fresh water from a supply line 131 into the washing machine 110 based on the level of treated water.
[0031] In one embodiment, the three-way inlet valve 120 is configured to either allow water into the storage tank 101 or to bypass from the water inlet 102 to the drain based on inputs from the water quality sensor 161 affixed to the inlet, or the level sensors 150, or both. In one embodiment, the three-way valve 120 is configured to drain water through drain 106 via bypass if the water quality sensor 161 affixed to the water inlet 102 detects the quality to be below a threshold value, or if the water level in the storage tank 101 is above a threshold value.
[0032] In one embodiment, the three-way outlet valve 130 is configured to either allow treated water from the water outlet 103 of the storage tank 101 or fresh water 131 from the supply line to the washing machine 110. In one embodiment, the control system 105 is configurable for manual selection of treatment of rinse water, wash water or both. In one embodiment, the treatment of rinse or wash water is selected automatically based on inputs from the level sensor 150 or water quality sensor 160. In one embodiment, the quantities of flocculating agent, the coagulating agent or the disinfecting agent are added in response to the input from the level sensor 150 or water quality sensor 160. In one embodiment, the control system 105 is further configured to drain the storage tank 101 when the level of treated water falls below a threshold.
[0033] In one embodiment, the water quality sensor 160 is a conductivity sensor. In some embodiments, the level sensor 150 is a mechanical float sensor, magnetic, capacitance, optical or microwave sensor. In one embodiment, the control system 105 is configured to recognize water inlet demand, outlet demand or the status of the operational cycle of the washing machine 110. In one embodiment, the use of treated water or fresh water is based on inputs from the level sensor 150 or the water quality sensor 160 affixed to the tank 101, or status of the operational cycle. In one embodiment, the apparatus 100 further comprising a software or hardware means for selecting between automatic and manual modes of operation.
[0034] In one embodiment, if the water inlet demand required for rinse or wash cycle of the washing machine 110, the control system 105 checks for availability of the treated water in the storage tank 101 using the level sensor 150. If treated water is available, the

control system 105 passes signal to open the water outlet valve 130 and close the freshwater valve 131. If the treated water is not available or in a low level, the control system 150 passes signal to open the freshwater valve 131 and close the water outlet valve
130 of the apparatus 100. In one embodiment, the status of water inlet demand and level of
the treated water are monitored by the level sensor 150.
[0035] In one embodiment, if the water inlet demand required for the final rinse in the washing machine 110, the control system 105 passes signal to open the freshwater valve
131 and close the water outlet valve 130. In various embodiments, the control system 105
is configured so that the spent water from soak, first wash or first rinse operations, valve
120 opens to drain 106.
[0036] In one embodiment, the method 200 of treating wash or rinse water in the storage tank with reference to FIG. 1 is shown in FIG. 2. In one embodiment, the method 200 includes introducing raw wash or rinse water by washing machine 110 inlet demand into a treatment module 104 of the tank 101 in step 201. In step 202, the method 200 comprises checking the level or quality of raw water using a level 150 or water quality sensor 160. In step 203, the method 200 comprises injecting the chemicals from the treatment module 104 based on sensed inputs. In some embodiments, the chemicals include flocculating agent, coagulating agent or disinfecting agent. In step 204, the method 200 comprises treating the raw using an agitator 107 for predetermined time based on the sensed inputs. In step 205, the method 200 comprises storing the treated water in the storage tank 101 and re-used on washing machine inlet demand.
[0037] In one embodiment, the treatment further comprises injecting the flocculating agent, the coagulating agent or the disinfecting agent in a predetermined cycle in step 203. In one embodiment, the flocculating agent, the coagulating agent or the disinfecting agent are injected in a predetermined sequence and in quantities determined based on inputs from the water quality sensor 160 affixed to the tank or the level sensors 150, or both. In one embodiment, the predetermined cycle further comprises agitator operation or hold time. In one embodiment, the flocculating agent is one of aluminium sulphate, calcium oxide, polyacrylamide or sodium silicate. In one embodiment, the coagulating agent is one of alum, aluminium chloride, calcium hypochlorite, ferric chloride or ferric sulphate. In

one embodiment, the disinfecting agent is one of chlorine, chlorine dioxide, hypochlorite or ozone.
[0038] In one embodiment, the water recycling apparatus 100 is interfaced in such a way that the control system 105 recognizes the water inlet demand and water outlet demand from the washing machine 110. In one embodiment, the control system 105 controls the water inlet 120 and outlet valves 130 as per a pre-defined operating sequence based on the demand, with reference to FIG. 1 as indicated in FIG. 3. These operations are termed as pre-defined subroutines such as water in procedure call and water out procedure call.
[0039] In one embodiment, a method for water in procedure call in the operating sequence of the apparatus 100 with reference to FIG. 3 is shown in FIG. 4. In one embodiment, the control system 105 initiates water inlet demand in the beginning or during the wash cycle of the washing machine 110. In one embodiment, the control system 105 recognizes the demand and checks the state of wash cycle in which the demand is initiated.
[0040] In one embodiment, if the water in demand is raised for soak, wash or first rinse or second rinse, the control system 105 checks the availability of recycled water in the apparatus 100. In one embodiment, the parameters such as water in demand status and recycled water level status are continuously monitored by the level 150 or quality sensor 160 of the control system 105. If the recycled water is available, the control system passes signal to open the recycled water valve 132 for the washing machine 110 and close the freshwater valve 131. The valves are kept in this position until there is a change in any of these two parameters.
[0041] In one embodiment, if recycled water level status from the level sensor 150 goes lower than threshold value, then the fresh water valve 131 will be opened and the recycled water valve 132 will be closed. In one embodiment, if recycled water quality status from the quality sensor 160 goes lower than threshold value, then the fresh water valve 131 will be opened and the recycled water valve 132 will be closed. In one embodiment, whenever the water in demand signal from the washing machine is turned low, the water in procedure call ends and control system 105 waits for water out demand signal. In one embodiment, if water in demand is raised for the final rinse, then the fresh water valve 131 will be opened and recycled water valve 132 will be closed.

[0042] In one embodiment, a method for water out procedure call in the operating sequence of the apparatus 100 with reference to FIG. 3 is shown in FIG. 5. In one embodiment, the control system 105 initiates the water out demand to drain the used water from the washing machine 110 during a wash or rinse cycle. In one embodiment, if water out demand is for soak, wash or first rinse, the spent water is drained through drain valve 106 will be opened and water inlet 102 to the tank 101 will be closed. The water out demand status is monitored by the level 150 or quality 160 sensor of the control system 105 and the respective valves are kept in the set position.
[0043] In one embodiment, if water out demand is raised for second rinse or third rinse, the water level in the storage tank 105 will be checked. If the storage tank 105 is empty or partially filled, the water inlet valve 120 to the storage tank 105 will be opened and water inlet valve to the drain will be closed. In this condition, the used water from washing machine 110 will be pumped to the treatment module 104 of the storage tank 101 for treatment.
[0044] In one embodiment, if recycled water level in the tank 101 is full or higher than the threshold level as sensed by the level sensor 150, the water inlet valve 120 to the tank 105 will be closed and the drain 106 will be opened. In one embodiment, whenever the water out demand signal from the washing machine 110 is turned low, the water out procedure call ends and control system 105 waits for the water in demand signal.
[0045] The water recycling or reuse apparatus protect the environment from pollution and preserve the resources. The apparatus is developed to treat and utilize the wash water as rinse water in the entire cycle of washing operation, with fully automated control system, so that it is possible to reduce the use of potable water in a household. The apparatus provides treatment of wash or rinse water from the washing machine cost effectively and efficiently with fully automated control system for reuse.
[0046] While the invention has been disclosed with reference to certain embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted without departing from the scope of the invention. In addition, many modifications may be made to adapt to a particular situation or material the teachings of the invention without departing from its scope. Any other apparatus for water recycling constructed and used in the manner illustrated, also fall within the scope of the

invention as further illustrated with reference to the examples below. However, the examples are not to be construed as limiting the scope of the invention as defined by the appended claims.
EXAMPLES Example – 1
[0047] In most of the washing machines, following operations take place during a washing cycle:
1. Soak and wash
2. First rinse – rinse 1
3. Second rinse – rinse 2
4. Final rinse and spin – rinse 3
[0048] FIG. 6 illustrates a schematic for an apparatus for washing machine rinse water treatment. The above-mentioned operations are controlled by an in-built integral control system of the apparatus, which is completely interfaced with the washing machine. During the washing cycle, the washing machine takes the required quantity of water through the water inlet valve and the used water is pumped-out through the water outlet valve with the help of a pump.
Example – 2 Chemical processing treatments done by water recycling apparatus (WRA)
[0049] Various treatment trails can be used for treating the wash water to achieve the water quality required for reusing the water. One of the option is coagulation, flocculation, disinfection followed by filtration. Coagulation and flocculation is a physicochemical process commonly used in water and wastewater treatment for the removal of colloidal and, to a certain extent, dissolved solids. This process involves the addition of required quantities of coagulants, followed by a short duration of rapid mixing and prolonged slow mixing. Disinfection process is used for the destruction of pathogens. Coagulants used for the study were alum (Al2 (SO4)3. 16 H2O, Analytical Grade (Merck, India) and poly aluminum chloride (PAC) (Rankem chemicals, India), Calcium hypochlorite (Ca (ClO)2) (SB chemicals, India), was used as the disinfectant.

[0050] Step 1:
The raw wash water was characterized for physico-chemical parameters like pH, turbidity and fecal contamination. The raw water characteristics and treated water characteristics are shown in Table 1.
[0051] Step 2:
The optimum coagulant doses were found out for each rinse (rinse1, rinse 2 and rinse 3) separately using jar test apparatus (Ever flow, India). It was found that the optimum coagulant doses for rinse 1 was: 150 mg/L of alum, 150 mg/L of calcium hypo and 1.0 mg/L of PAC. For rinse 2, the chemical requirement was: 10 mg/L of alum, 20 mg/L calcium hypo and 0.3 mg/L of PAC. For rinse 3, the chemical requirement was: 0.3 mg/L of alum, 1.0 mg/L of calcium hypo and 0.5 mg/L of PAC.
[0052] Step 3:
Laboratory scale studies were carried using the experimental water recycling apparatus (WRA). This experimental system had completely automated control systems.
Example – 3
[0053] Experiments were carried out as per the procedure mentioned in the previous section and the treated water was analyzed for various parameters. The results are given in Table 2. From the experimental results, it was observed that the treated water quality of rinse 1 was not as good as rinse 2 and rinse 3. Hence, only the rinse 2 and rinse 3 wash water were considered for treatment and reuse.

[0054] While the invention has been described with a certain degree of particularity, it is manifest that many changes may be made in the details of construction and the arrangement of components without departing from the spirit and scope of this disclosure. It is understood that the invention is not limited to the embodiments and examples set forth herein for purposes of exemplification, but is to be limited only by the scope of the attached claims, including the full range of equivalency to which each element thereof is entitled.