Claims:CLAIMS
I/We Claim:
1. A sewage sludge brick (102), wherein the sewage sludge brick (102) comprising:
Incinerated Sewage Sludge (ISS) (104) in a range of 10% to 40% by weight;
a mixture of clay (106) and red soil (108) in a range of 31% to 60% by weight;
sand (110) in a range of 17% to 28% by weight;
12% by weight of fly ash (112); and
water (114) in a range of 40 Liters (L) to 44 L.
2. The brick as claimed in claim 1, wherein the ISS (104) is produced by incinerating oven dried sewage sludge at 800 °C for 3 hours and 30 minutes.
3. The brick as claimed in claim 2, wherein the sewage sludge is oven dried at 105°C for 24 hours.
4. The brick as claimed in claim 1, wherein rice husk (116) is added to the sewage sludge brick (102).
5. The brick as claimed in claim 1, wherein a particle size of the ISS (104) is in a range of 100 Micrometer (µm) to 150 µm.
6. A method for manufacturing a sewage sludge brick (102), the method comprising steps of:
collecting sewage sludge from a sewage treatment plant;
drying the collected sewage sludge in an oven at 105°C for 24 hours for lowering a moisture content in the collected sewage sludge;
incinerating the dried sewage sludge for 3 hours and 30 minutes at 800°C;
grinding the Incinerated Sewage Sludge (ISS) (104) using a ball mill to attain a particle size in a range of 100 Micrometer (µm) to 150 µm;
adding the grinded ISS (104) in a range of 10% to 40% by weight, a mixture of clay (106) and red soil (108) in a range of 31% to 60% by weight, sand (110) in a range of 17% to 28% by weight, 12% by weight of fly ash (112); rice husk (116), and water (114) in a range of 40 Liters (L) to 44 L in a mixer;
casting the mixture of the sewage sludge brick (102) using a brick mold, wherein a size of the brick mold is 20 Centimeters (cm) x 10 cm x 5 cm; and
testing the casted sewage sludge brick (102) for properties selected from one of, dimensions, a compressive strength, a water absorption, an efflorescence, or a combination thereof.
7. The method as claimed in claim 6, wherein a particle size of the ISS (104) is less than 150 Micrometer (µm).
8. The method as claimed in claim 6, wherein the water absorption of the casted sewage sludge brick (102) is in the range of 12.86% to 31.29%.
9. The method as claimed in claim 6, wherein the compressive strength of the casted sewage sludge brick (102) is in a range of 3.12 Newton per square millimeter (N/mm²) to 4.53 N/mm².
10. The method as claimed in claim 6, wherein the efflorescence of the casted sewage sludge brick (102) is in a range of 10% to 50%.
Date: 8th August 2020
Place: Noida

Dr. Keerti Gupta
Agent for the Applicant
(IN/PA-1529)

, Description:FORM 2

THE PATENT ACT 1970
(39 of 1970)
&

THE PATENTS RULES, 2003

COMPLETE SPECIFICATION
(See Section 10, and rule 13)

TITLE OF THE INVENTION
METHOD FOR MANUFACTURING SEWAGE SLUDGE BRICK
APPLICANT(S)
NAME: Dr. P. Murthi
NATIONALITY: INDIAN
ADDRESS: S R Engineering College, Ananthasagar (V), Hasanparthy (M), Warangal, Telangana, 560 371

The following specification particularly describes the invention and the manner in which it is to be performed
BACKGROUND
Field of Invention
[001] Embodiments of the present invention generally relate to a method for utilizing a waste product, and more particularly to a method for manufacturing bricks from a waste product generated from sewage.
Description of Related Art
[002] The disposal of sewage water is a major problem in urban cities and causes harmful effects on the environment. Sludge is a main product from sewage waste and a disposal of the sewage sludge is an environmental issue. Moreover, the disposal of the sewage sludge needs more land space and incur a large cost. The sewage sludge needs to be utilized by recycling it to a valuable product such as, a masonry brick.
[003] Conventionally, the masonry bricks are prepared by using clay and various industrial wastes. Many researches have been carried out on effective utilization of the sewage sludge in the construction industry as the sewage sludge possess similar properties like the clay, which can be utilized in making different construction materials. CN101941829A discloses sludge bricks and a production method thereof. The method is characterized such that the sludge from sedimentation tanks of chemical plants, machine plants, sugar plants, cotton spinning plants and on streets is drained or dried; clay is selected from yellow soil, grassland soil or orchard soil; and coal dust is selected from industrial or domestic coal, the sludge, the clay and the coal dust are proportionally mixed and stirred, the mixture is pressed into brick green bodies by molds and the brick green bodies are placed into a brick kiln to be roasted into bricks for buildings, or the mixture can be pressed into flooring brick green bodies by floor brick molds and the flooring brick green bodies are roasted into the floor bricks for flooring. The bricks have complete and neat appearances and high strength and conform to the national standard environmental protection requirement. US6440884B1 discloses a process for building bricks and tiles by mixing 60% to 75% clay, 20% to 40% sludge and 1% to 10% sand, all percentages being by weight of total composition. CN102153330B discloses a preparation method for a sludge baked brick resisting leaching of heavy metal. The preparation method includes the steps as follows: (1) adding boric acid in water glass and stirring to obtain sodium borosilicate ternary sol original solution; and then adding water for mixture to obtain sodium borosilicate ternary sol diluted solution; (2) adding the diluted solution in sludge, wherein the added diluted solution accounts for 8%-15% sludge in quantity, stirring, and standing for 12-24 hours; and (3) baking according to conventional flow, so that the sludge baked brick can be obtained. DE2336267B2 discloses a process for disposal of sewage sludge for preparation of bricks. CN107324710A discloses a kind of preparation method for sludge organism charcoal water- permeable brick for possessing high absorption. CN1108201C discloses a method of using a light brick fired thermal sludge, which is separated from the belt filter press dewatering to a moisture content of 50 to 60%, and a particle diameter of 3 - 9mm pellets, then a proportion of 10 to 30%, the dried pellets homogeneously mixed and then formed raw material clay brick tile, drying, and finally, calcined according to claim fired into bricks. CN101830687B discloses a method for producing bricks from silt and sludge. CN101318805 discloses a method for manufacturing and sintering brick permeable to water with urban sewage sludge and wet-discharged coal ash. CN103044006A discloses a method for preparing environment friendly water permeable bricks by using water supply sludge.
[004] There is thus a need for managing waste such as the sewage sludge in a more efficient manner to produce construction materials having better properties.
SUMMARY
[005] Embodiments in accordance with the present invention provide a sewage sludge brick. The sewage sludge brick comprising: Incinerated Sewage Sludge (ISS) in a range of 10% to 40% by weight; a mixture of clay and red soil in a range of 31% to 60% by weight; sand in a range of 17% to 28% by weight; 12% by weight of fly ash; and water in a range of 40 Liters (L) to 44 L.
[006] Embodiments in accordance with the present invention further provide a method for manufacturing a sewage sludge brick. The method comprising steps of: collecting sewage sludge from a sewage treatment plant; drying the collected sewage sludge in an oven at 105°C for 24 hours for lowering a moisture content in the collected sewage sludge; incinerating the dried sewage sludge for 3 hours and 30 minutes at 800°C; grinding the Incinerated Sewage Sludge (ISS) using a ball mill to attain a particle size of 150 Micrometer (µm); adding the grinded ISS in a range of 10% to 40% by weight, a mixture of clay and red soil in a range of 31% to 60% by weight, sand in a range of 17% to 28% by weight, 12% by weight of fly ash; rice husk, and water in a range of 40 Liters (L) to 44 L in a mixer; casting the sewage sludge brick using a brick mold, wherein a size of the brick mold is 20 Centimeters (cm) x 10 cm x 5 cm; testing the casted sewage sludge brick for properties selected from one of, dimensions, a compressive strength, a water absorption, an efflorescence, or a combination thereof.
[007] Embodiments of the present invention may provide a number of advantages depending on its particular configuration. First, embodiments of the present application provide a method for manufacturing sewage sludge brick. Next, embodiments of the present application may provide a method to avoid and remove hazardous chemicals of sewage before adding into the sewage sludge brick. Next, embodiment of the present application provides a method for manufacturing sewage sludge brick having increased dimensional stability. Next, embodiment of the present application provides sewage sludge brick having low efflorescence.
[008] These and other advantages will be apparent from the present application of the embodiments described herein.
[009] The preceding is a simplified summary to provide an understanding of some embodiments of the present invention. This summary is neither an extensive nor exhaustive overview of the present invention and its various embodiments. The summary presents selected concepts of the embodiments of the present invention in a simplified form as an introduction to the more detailed description presented below. As will be appreciated, other embodiments of the present invention are possible utilizing, alone or in combination, one or more of the features set forth above or described in detail below.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] The above and still further features and advantages of embodiments of the present invention will become apparent upon consideration of the following detailed description of embodiments thereof, especially when taken in conjunction with the accompanying drawings, and wherein:
[0011] FIG. 1 illustrates a block diagram depicting a mixture for manufacturing a sewage sludge brick, according to an embodiment of the present invention disclosed herein; and
[0012] FIG. 2 depicts a flowchart of a method for manufacturing the sewage sludge brick, according to an embodiment of the present invention disclosed herein.
[0013] The headings used herein are for organizational purposes only and are not meant to be used to limit the scope of the description or the claims. As used throughout this application, the word "may" is used in a permissive sense (i.e., meaning having the potential to), rather than the mandatory sense (i.e., meaning must). Similarly, the words “include”, “including”, and “includes” mean including but not limited to. To facilitate understanding, like reference numerals have been used, where possible, to designate like elements common to the figures. Optional portions of the figures may be illustrated using dashed or dotted lines, unless the context of usage indicates otherwise.
DETAILED DESCRIPTION
[0014] The following description includes the preferred best mode of one embodiment of the present invention. It will be clear from this description of the invention that the invention is not limited to these illustrated embodiments but that the invention also includes a variety of modifications and embodiments thereto. Therefore, the present description should be seen as illustrative and not limiting. While the invention is susceptible to various modifications and alternative constructions, it should be understood, that there is no intention to limit the invention to the specific form disclosed, but, on the contrary, the invention is to cover all modifications, alternative constructions, and equivalents falling within the spirit and scope of the invention as defined in the claims.
[0015] In any embodiment described herein, the open-ended terms "comprising," "comprises,” and the like (which are synonymous with "including," "having” and "characterized by") may be replaced by the respective partially closed phrases "consisting essentially of," consists essentially of," and the like or the respective closed phrases "consisting of," "consists of, the like.
[0016] As used herein, the singular forms “a”, “an”, and “the” designate both the singular and the plural, unless expressly stated to designate the singular only.
[0017] FIG. 1 illustrates a block diagram of a mixture 100 for manufacturing a sewage sludge brick 102, according to an embodiment of the present invention. The sewage sludge brick 102 may comprise Incinerated Sewage Sludge (ISS) 104, clay 106, red soil 108, sand 110, fly ash 112, water 114, and rice husk 116. Further, the ISS 104, the clay 106, the red soil 108, the sand 110, the fly ash 112, and water 114 may be mixed in a mixer 118, according to an embodiment of the present invention.
[0018] The ISS 104 may be produced from sewage sludge using an incineration process. The sewage sludge may be collected from a sewage treatment plant, in an embodiment of the present invention. Further, the incineration process may be a waste treatment process used for combustion of organic substances present in the sewage sludge at a high temperature. In an embodiment of the present invention, the sewage sludge may be dried in an oven (not shown) at 105°C for 24 hours to lower a moisture content in the sewage sludge. Further, the dried sewage sludge may be incinerated for 3 hours and 30 minutes at 800°C to produce the ISS 104. In an embodiment of the present invention, the ISS 104 may be further grinded using a grinding mill (not shown). According to embodiments of the present invention, the grinding mill may be, but not limited to, a rod mill, an autogenous mill, a Semi-Autogenous Grinding (SAG) mill, a pebble mill, a buhrstone mill, a tower mill, and so forth. In a preferred embodiment of the present invention, the grinding mill may be a ball mill. Embodiments of the present invention are intended to include or otherwise cover any type of the grinding mill, including known, related art, and/or later developed technologies. Further, the ISS 104 may be grinded to attain a particle size in range of 100 Micrometer (µm) to 150 µm. In a preferred embodiment of the present invention, the ISS 106 may be grinded in the grinding mill to attain a particle size such that the particles of the ISS 104 may pass through a 150 µm sieve. According to embodiments of the present invention, a proportion of the ISS 104 used in the manufacturing of the sewage sludge brick 102 may be in a range of 10% to 40% by weight as shown in TABLE 1.
[0019] The clay 106 may be a type of finely grained natural soil material containing hydrous aluminum phyllosilicates that may develop plasticity upon interacting with the water 114. According to embodiments of the present invention, the clay 106 may be premixed with the red soil 108 to form a mixture. The red soil 108 may be a type of soil derived from crystalline rocks and may contain ferric oxides that may provide a low water holding capacity. Further, the red soil 108 may have thin organic-mineral layers overlying a yellowish-brown leached layer resting on an illuvium red layer.
[0020] The sand 110 may be a type of granular material containing silicon dioxide in form of quartz. The sand 110 may be a naturally occurring material formed as a result of weathering process that may break a rock and/or a mineral into small grains in the formation of the sand 110. In an embodiment of the present invention, the sand 110 may be a locally available sand. In an embodiment of the present invention, the sand 110 may be, but not limited to, a zone I type sand as per Indian Standard (IS) 353:1970, a zone II type sand as per IS 353:1970, a zone III type sand as per IS 353:1970, a zone IV type sand as per IS 353:1970, and so forth. Embodiments of the present invention are intended to include or otherwise cover any type of the sand 110, including known, related art, and/or later developed technologies. According to embodiments of the present invention, a proportion of the sand 110 used in the manufacturing of the sewage sludge brick 102 may be in a range of 17% to 28% by weight as shown in the TABLE 1.
[0021] The fly ash 112 may be a fine powder that may be produced as a byproduct of a coal burnt in a coal power plant. Further, the fly ash 112 may be a pozzolan that may contain an aluminous and a siliceous material capable of forming cement in a presence of the water 114. According to embodiments of the present invention, a proportion of the fly ash 112 used in the manufacturing of the sewage sludge brick 102 may be 12% by weight as shown in the TABLE 1. The water 114 may be a locally available water 114 that may be used in the manufacturing of the sewage sludge brick 102. The water 114 may be added to the mixer 118 in the range of 40 Liters (L) to 44 L, as shown in the TABLE 1.
[0022] The rise husk 116 may be a hard protection covering of grains of rice that may be extracted using a process of winnowing. The rise husk 116 may have a capability to catch fire easily, due to which the rice husk 116 may be added to the mixture 100 to easily fire the sewage sludge brick 102 in a kiln (not shown). According to embodiments of the present invention, the mixer 118 may be a type of concrete mixer that may be designed to mix different materials to form a homogeneous mixture 100. The mixer 118 may be, but not limited to, a batch mixer, a tilting drum mixer, a non-tilting drum mixer, a reversing drum mixer, a continuous concrete mixer, a pan mixer and so forth. Embodiments of the present invention are intended to include or otherwise cover any type of the mixer 118, including known, related art, and/or later developed technologies.
Table 1: Details of mix proportions
Incinerated Sewage Sludge (ISS) 104 Clay 106 and Red soil 108 Sand 110 Fly ash 112 Water 114
Mix 1 0% 60% 28% 12% 0 L
Mix 2 10% 52% 26% 12% 40 L
Mix 3 20% 45% 23% 12% 42 L
Mix 4 30% 38% 20% 12% 44 L
Mix 5 40% 31% 17% 12% 42 L
[0023] Table 1 depicts various mix proportions of the ISS 104, the clay 106, the red soil 108, the sand 110, the fly ash 112 and water 114 used to make the sewage sludge brick 102, according to embodiments of the present invention. According to an embodiment of the present invention, a user may prepare a Mix 1 by adding 60% by weight of the mixture made up of the clay 106 and the red soil 108, 28% by weight of the sand 110, and 12% by weight of the fly ash 112 into the mixer 118 for creating the mixture 100. The user may be, but not limited to, a student, a researcher, a construction worker, and so forth. Embodiments of the present invention are intended to include or otherwise cover any of the user making the sewage sludge brick 102. Further, the mixture 100 may be uniformly mixed in the mixer 118 for a predefined time period. In an embodiment of the present invention, the predefined time period may be in a range of 2 minutes to 10 minutes. Embodiments of the present invention are intended to include or otherwise cover any of the predefined time periods. Further, the rice husk 116 may be added to the mixture 100. According to embodiment of the present invention, the mixture 100 may be left undisturbed for a period of 24 hours.
[0024] According to another embodiment of the present invention, a Mix 2 may be prepared by adding 10% by weight of the ISS 104, 52% by weight of the mixture containing the clay 106 and the red soil 108, 26% by weight of the sand 110, 12% by weight of the fly ash 112, and 40 L of the water 114 into the mixer 118 by the user for creating the mixture 100. Further, the mixture 100 may be uniformly mixed in the mixer 118 for the predefined time period. Furthermore, the rice husk 116 may be added to the mixture 100. According to embodiment of the present invention, the mixture 100 may be left undisturbed for the period of 24 hours for the clay 106 to absorb the water 114. According to yet another embodiment of the present invention, a Mix 3 may be prepared by adding 20% by weight of the ISS 104, 45% by weight of the mixture containing the clay 106 and the red soil 108, 23% by weight of the sand 110, 12% by weight of the fly ash 112, and 42 L of the water 114 into the mixer 118 by the user for creating the mixture 100. Further, the mixture 100 may be uniformly mixed in the mixer 118 for the predefined time period. Furthermore, the rice husk 116 may be added to the mixture 100. According to embodiment of the present invention, the mixture 100 may be left undisturbed for the period of 24 hours for the clay 106 to absorb the water 114.
[0025] According to yet another embodiment of the present invention, a Mix 4 may be prepared by adding 30% by weight of the ISS 104, 38% by weight of the mixture containing the clay 106 and the red soil 108, 20% by weight of the sand 110, 12% by weight of the fly ash 112, and 44 L of the water 114 into the mixer 118 by the user for creating the mixture 100. Further, the mixture 100 may be uniformly mixed in the mixer 118 for the predefined time period. Furthermore, the rice husk 116 may be added to the mixture 100. According to embodiment of the present invention, the mixture 100 may be left undisturbed for the period of 24 hours for the clay 106 to absorb the water 114.
[0026] According to yet another embodiment of the present invention, a Mix 5 may be prepared by adding 40% by weight of the ISS 104, 31% by weight of mixture containing the clay 106 and the red soil 108, 17% by weight of the sand 110, 12% by weight of the fly ash 112, and 42 L of the water 114 into the mixer 118 by the user for creating the mixture 100. Further, the mixture 100 may be uniformly mixed in the mixer 118 for the predefined time period. Furthermore, the rice husk 116 may be added to the mixture 100. According to embodiment of the present invention, the mixture 100 may be left undisturbed for the period of 24 hours for the clay 106 to absorb the water 114. According to embodiments of the present invention, a brick mold (not shown) may be used to cast the sewage sludge brick 102 using the Mix 1, the Mix 2, the Mix 3, the Mix 4, and the Mix 5. The brick mold may have dimensions equal to 20 centimeters (cm) x 10 cm x 5 cm, according to embodiments of the present invention.
[0027] According to embodiments of the present invention, the sewage sludge brick 102 casted using the Mix 1, the Mix 2, the Mix 3, the Mix 4, and the Mix 5 may be baked in a kiln (not shown). The kiln may be a type of oven used to bake the sewage sludge brick 102. The kiln may be, but not limited to, a Hoffmann kiln, a bull’s trench kiln, a habla kiln, a roller kiln, a clamp kiln, a skove kiln, a scotch kiln, a down draft kiln, a shuttle Kiln, a retort kiln, an electric kiln, a feller kiln, a Top-hat kiln and so forth. Embodiments of the present invention are intended to include or otherwise cover any type of the kiln, including known, related art, and/or later developed technologies.
[0028] According to embodiments of the present invention, the user may further test the sewage sludge brick 102 casted using the Mix 1, the Mix 2, the Mix 3, the Mix 4, and the Mix 5 for determining properties of the sewage sludge brick 102. The properties may be, but not limited to, dimensions, a compressive strength, a water absorption, an efflorescence, and so forth. Embodiments of the present invention are intended to include or otherwise cover any of the properties of the sewage sludge brick 102, including known, related art, and/or later developed technologies.
[0029] The user may check a surface condition of each of the sewage sludge brick 102 casted using the Mix 1, the Mix 2, the Mix 3, the Mix 4, and the Mix 5. Further, the user may measure the dimensions of each of the sewage sludge brick 102 casted using the Mix 1, the Mix 2, the Mix 3, the Mix 4, and the Mix 5 with 1 Millimeter (mm) accuracy. According to an embodiment of the present invention, the surface condition of each of the sewage sludge brick 102 casted using the Mix 4 and the sewage sludge brick 102 casted using the Mix 5 may not be perfect and edges may be slightly damaged as compared to the sewage sludge brick 102 casted using the Mix 1, the Mix 2, and the Mix 3. Further, the dimensions of the sewage sludge brick 102 casted using the Mix 4 and the sewage sludge brick 102 casted using the Mix 5 may not be accurate when compared to the sewage sludge brick 102 casted using the Mix 1, the Mix 2, and the Mix 3.
[0030] The compressive strength of the sewage sludge brick 102 may be defined as a ratio between a failure load to a cross sectional area of the sewage sludge brick 102. According to embodiments of the present invention, the compressive strength of the sewage sludge brick 102 may be determined by testing the sewage sludge brick 102 using a compression testing machine (not shown). The compressive strength of the sewage sludge brick 102 may be tested using a procedure as per Indian Standard 3495 (Part-2). In an exemplary scenario, the procedure for determining the compressive strength of the sewage sludge brick 102 includes a step of measuring dimensions of a top surface (hereinafter referred to as a frog side) of the sewage sludge brick 102. The frog side may be measured to a nearest of 1 millimeter (mm). Further, any unevenness on a bed face of the frog side and on an opposite side of the sewage sludge brick 102 needs to be removed. Furthermore, all voids on the bed face may be filled with a cement mortar. According to an embodiment of the present invention, the cement mortar may be made up of cement, clean coarse sand of grade 3 Millimeters (mm) and below mixed in a ratio of 1:1. Further, the sewage sludge brick 102 may be stored under a damp jute bag for a period of 24 hours. Furthermore, the sewage sludge brick 102 may be immersed in clean water for a period of 3 days. The sewage sludge brick 102 may be removed from the clean water and wiped to remove traces of moisture from the sewage sludge brick 102. According to an embodiment of the present invention, the sewage sludge brick 102 may be placed with flat faces horizontal and the cement mortar filled frog side facing upwards between two 3-ply plywood sheets each having a thickness of 3 mm. The sewage sludge brick 102 may be sandwiched between the 3-ply plywood sheets to ensure a uniform distribution of a load from plates of the compression testing machine. According to an embodiment of the present invention, the load may be applied axially at a uniform rate of 14 Newton Per Square Millimeter (N/mm²) per minute to determine the compressive strength of the sewage sludge brick 102. According to an embodiment of the present invention, the compressive strength of the sewage sludge brick 102 may be calculated using a mathematical expression such as:
Compressive strength of the sewage sludge brick (102) = Maximum Load at Failure (Newton)/Average area of the bed face of the sewage sludge brick (102) in Millimeter square (mm²)
[0031] According to an embodiment of the present invention, the compressive strength value of the sewage sludge brick 102 made up of the Mix 1 to the Mix 5 may be in a range of 4.53 N/mm² to 3.12 N/mm². According to an embodiment of the present invention, an average compressive strength of the sewage sludge brick 102 may be 3.184 N/mm².
[0032] The water absorption test may be carried out by immersing the sewage sludge brick 102 casted from the Mix 1 to the Mix 5 for about 24 hours in portable water. The water absorption test on the sewage sludge brick 102 may be conducted to determine durability properties of the sewage sludge brick 102. The durability properties may be, but not limited to, a degree of burning, a quality of the sewage sludge brick 102 and a behavior of the sewage sludge brick 102 brick in weathering. In an exemplary scenario, a procedure for determining the water absorption of the sewage sludge brick 102 includes a step of drying the sewage sludge brick 102 in an oven (not shown). According to embodiments of the present invention, the temperature of the oven may be in the range of 105°Celsius (C) to 115°C. The sewage sludge brick 102 may be dried in the oven till the sewage sludge brick 102 attains substantial constant mass. The sewage sludge brick 102 may be cooled at a room temperature and the sewage sludge brick 102 may be further measured to obtain an initial weight (W1). Further, the sewage sludge brick 102 may be immersed in clean water at a temperature of 27 ± 2°C for a period of 24 hours. Next, the sewage sludge brick 102 may be wiped off with a clean cloth for avoiding dripping water. The sewage sludge brick 102 may be weighed to obtain a final weight (W2) to determine a change in a dry weight of the sewage sludge brick 102. The water absorption of the sewage sludge brick 102 may be calculated using a mathematical expression such as:
Water absorption % by mass = [(W2 - W1) / W1] x 100
[0033] The water absorption value of the sewage sludge brick 102 casted from the Mix 1 to the Mix 5 may be in a range of 12.86% to 31.29%. According to an embodiment of the present invention, the average water absorption of the sewage sludge brick 102 may be 20.82%.
[0034] According to an embodiment so of the present invention, a soluble salt such as, a magnesium sulphate, a calcium sulfate, a carbonate of sodium, a carbonate of potassium present in the sewage sludge brick 102 may cause efflorescence on a surface of the sewage sludge brick 102. In an exemplary scenario, a procedure for determining the efflorescence on the surface of the sewage sludge brick 102 includes a step of placing one of an end of the sewage sludge brick 102 in a shallow dish (not shown) filled with distilled water. The distilled water may be filled in the shallow dish such that the sewage sludge brick 102 may immerse in the distilled water up to a depth of 25 mm. Further, the shallow dish with the sewage sludge brick 102 immersed in the distilled water may be kept in a warm ventilated room such that the whole distilled water may be absorbed by the sewage sludge brick 102 while the surplus distilled water gets evaporated. The shallow dish may be covered by a glass cylinder (not shown) to stop an excessive evaporation from the shallow dish. After the whole of the distilled water is absorbed by the sewage sludge brick 102, a similar amount of distilled water is again added to the shallow dish and the process is repeated once again before examining the sewage sludge brick 102 for the efflorescence. Next, the sewage sludge brick 102 may be observed and the efflorescence results may be noted. The results may be categorized as, but not limited to, NIL if there is an absence of grey or white deposits of the soluble salts on the surface of the sewage sludge brick 102, SLIGHT if there is a presence of the grey or white deposits of the soluble salts on less than 10% surface area of the sewage sludge brick 102, MODERATE if there is a heavy deposit of grey or white deposits of the soluble salts on up to 50% of the surface area of the sewage sludge brick 102 but there may be an absence of powdering or flaking of the surface area of the sewage sludge brick 102, HEAVY if there is a heavy deposit of grey or white deposits of soluble salts covering up to 50% or more of the surface area of the sewage sludge brick 102 but still there may be no sign of powdering or flaking of the surface area of the sewage sludge brick 102, and SERIOUS if there is a heavy deposit of grey or white deposits of soluble salts on the surface area of the sewage sludge brick 102 along with a presence of powdering and flaking of the surface area of the sewage sludge brick 102, and so forth.
Table 2 : Test Results for the properties of the sewage sludge brick 102 casted using different mix proportions
Sludge content (%) Compressive strength(N/mm²) Water absorption (%) Efflorescence (%)
0 4.53 12.86 10-12
10 4.13 15.37 15-20
20 3.86 19.03 25
30 3.43 25.55 More than 40-50
40 3.12 31.29 More than 40-50

[0035] Table 2 depicts test results for the properties of the sewage sludge brick 102 casted from the Mix 1, the Mix 2, the Mix 3, the Mix 4, and the Mix 5. According to an embodiment of the present invention, the compressive strength of the sewage sludge brick 102 casted from the Mix 1 having 0% of the ISS 104 content may be 4.53 Newton per Millimeters square (N/mm2). Further, the water absorption of the sewage sludge brick 102 casted from the Mix 1 may be 12.86%. Furthermore, the efflorescence of the sewage sludge brick 102 casted from the Mix 1 may be categorized as Slight efflorescence and may be in a range of 10% to 12%. According to another embodiment of the present invention, the compressive strength of the sewage sludge brick 102 casted from the Mix 2 having 10% of the ISS 104 content may be 4.13 N/mm2. Further, the water absorption of the sewage sludge brick 102 casted from the Mix 2 may be 15.37%. Furthermore, the efflorescence of the sewage sludge brick 102 casted from the Mix 2 may be categorized as Moderate efflorescence and may be in a range of 15% to 20%.
[0036] According to yet another embodiment of the present invention, the compressive strength of the sewage sludge brick 102 casted from the Mix 3 having 20% of the ISS 104 content may be 3.86 N/mm2. Further, the water absorption of the sewage sludge brick 102 casted from the Mix 3 may be 19.03%. Furthermore, the efflorescence of the sewage sludge brick 102 casted from the Mix 3 may be categorized as Moderate efflorescence and may be in a range of 25%. According to yet another embodiment of the present invention, the compressive strength of the sewage sludge brick 102 casted from the Mix 4 having 30% of the ISS 104 content may be 3.43 N/mm2. Further, the water absorption of the sewage sludge brick 102 casted from the Mix 4 may be 25.55%. Furthermore, the efflorescence of the sewage sludge brick 102 casted from the Mix 4 may be categorized as Heavy efflorescence and may be more than 40% to 50%. According to yet another embodiment of the present invention, the compressive strength of the sewage sludge brick 102 casted from the Mix 5 having 40% of the ISS 104 content may be 3.12 N/mm2. Further, the water absorption of the sewage sludge brick 102 casted from the Mix 5 may be 31.29%. Furthermore, the efflorescence of the sewage sludge brick 102 casted from the Mix 5 may be categorized as Heavy efflorescence and may be more than 40% to 50%.
[0037] FIG. 2 depicts a flowchart of a method 200 for manufacturing the sewage sludge brick 102, according to an embodiment of the present invention.
[0038] At step 202, the user may collect sewage sludge from a sewage treatment plant.
[0039] At step 204, the user may dry the sewage sludge in an oven at 105°C for 24 hour for lowering the moisture content of the sewage sludge.
[0040] Next, at step 206, the user may incinerate the sewage sludge for 3 hours and 30 minutes at 800°C to produce the ISS 104.
[0041] At step 208, the user may grind the ISS 104 using a ball mill (not shown) to a particle size of 150 micron.
[0042] Further, at step 210, the user may add the ISS 104 in a range of 10% to 40% by weight, the mixture of the clay 106 and the red soil 108 in a range of 31% to 60% by weight, the sand 110 in a range of 17% to 28% by weight, 12% by weight of the fly ash 112, the rice husk 116 and the water 114 in a range of 40 L to 44 L in the mixer 118.
[0043] At step 212, the user may cast the sewage sludge brick 102 using the brick mold (not shown).
[0044] At step 214, the user may test the sewage sludge brick 102 for properties of the sewage sludge brick 102 such as, but not limited to, the dimensions, the compressive strength, the water absorption, the efflorescence, and so forth.
[0045] Embodiments of the invention are described above with reference to block diagrams and schematic illustrations of methods and systems according to embodiments of the invention. While the invention has been described in connection with what is presently considered to be the most practical and various embodiments, it is to be understood that the invention is not to be limited to the disclosed embodiments, but on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.
[0046] This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. The patentable scope the invention is defined in the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements within substantial differences from the literal languages of the claims.