Study on Interaction of Cement with Red Mud

Study on Interaction of Cement with Red Mud

Ms. Amulya Gudla Assistant Professor Civil Department

Kakatiya Institute of Technology & Science Warangal, India

Mr. Balivada Sailaxman Assistant Professor Civil Department

Kakatiya Institute of Technology & Science Warangal, India

Ms. Nukaraju Bharathi Assistant professor Civil Department

Kakatiya Institute of Technology & Science Warangal, India

Abstract- The process of producing aluminum from bauxite (Aluminum ore) yields a byproduct called RED MUD/RED

1. Red mud

   1. MATERIALS USED

      SLUDGE. Red mud is alkaline in nature which becomes hazardous if disposed in the environment. In the present study, an attempt is made to stabilize the Red mud by adding various percentages of cement. Tests like compaction, grain size distribution analysis, unconfined compressive strength, split tensile strength, permeability were conducted to study the interaction of Red mud and cement particles. Red mud was mixed with various percentages of cement (0, 5, 10, 15 and 20%) and cured for 3day, 7day, 14day and 28day by maintaining 100% humidity. From the test results it was identified that as the percentage of cement increases strength values in terms of compression increases. Maximum values were attained at 28 day curing periods. Compressive strength at 5%, 10%, 15% and 20% are 78, 110, 142, 175 kg/cm2 respectively.

      Keywords Bauxite, Cement, Modified Proctor test, Red mud, Stabilization, Split tensile strength, Unconfined compressive strength

      1. INTRODUCTION

   Red mud is one of the byproduct obtained during refining process of Bauxite (ore of Aluminum) and it is highly alkaline in nature due to presence of caustic soda. Its disposal is problematic and hazardous to environment. In order to overcome this problem it has to be reused in various civil engineering aspects.

   Ordinary Portland cement has been used as a stabilizer for different kinds of soils from past few decades. As cement composed of Calcium silicates and calcium-aluminates when combine with water, hydrates to form the cementing compounds called calcium silicate hydrate and calcium-aluminate-hydrate, as well as excess calcium hydroxide. Due to formation of above compounds, ordinary Portland cement may be successful in stabilizing both granular and fine-grained soils, as well as aggregates and miscellaneous materials. A Pozzolanic reaction between the calcium hydroxide (released during hydration process) and soil alumina and soil silica occurs in fine-grained clay soils. In this present study, an attempt is made to stabilize red mud

   by adding Ordinary Portland cement (Grade-53-Jaypee) in various percentages

   The amount of Red mud produced depends on the type and grade of Bauxite. In this present study the red mud was collected from NALCO (National Aluminum Company) which is located at Damanjodi in Orissa.

2. Cement

   Cement used in this work is Ordinary Portland Cement (53-grade) cement. The manufacturer of the cement used is Jaypee

   TABLE 1 CHEMICAL PROPERTIES OF RED MUD

   Properties	Values
   pH	11.68
   Bio carbonate extractable phosphorous	50.1
   Fe%	0.12
   Al%	1.49

   Properties	Value
   Appearance	Mud
   Color	Red
   Odor	Slightly pungent
   Specific Gravity	2.9
   Liquid Limit (%)	32
   Plastic Limit (%)	24
   Plasticity Index	08
   Grain Size Distribution
   a. Fine sand (%)	05
   b. Silt (%)	89
   c. clay(%)	06
   OMC (%)	22
   MDD (g/cc)	1.78
   UCS(Kg/cm2)	1.49
   CBR	4.00
   Permeability (cm/s)	4.3×10-6

   TABLE 2 GEOTECHNICAL PROPERTIES OF RED MUD

   TABLE 3 PHYSICAL PROPERTIES OF CEMENT

   Name of The Characteristics	Result
   Standard Consistency (%)	32
   Weight Per Bag (kg)	50
   Initial setting time (minutes)	128
   final setting time (minutes)	279
   Specific gravity	3.12
   Fineness (as retained on IS: No 90 micron sieve) (%)	2.50

   TABLE 4 ULTIMATE COMPRESSIVE STRENGTH OF CEMENT

   Curing Period (in days)	Ultimate compressive strength (MPa)
   3	28.6
   7	38.6
   28	58.4

   1. TESTS & RESULTS

      1. Modified Proctor Test for Red mud Cement Mix

         IS heavy compaction test was performed as per IS 2720 on Red mud with various percentages of cement such as 0, 5, 10, 15 and 20 respectively. The following observations were found.

         TABLE 5. COMPACTION CHARACTERISTICS OF RED MUD-CEMENT MIXES

         % of Cement	OMC (%)	MDD(g/cc)
         0	22.0	1.78
         5	23.5	1.75
         10	25.2	1.71
         15	27.0	1.66
         20	29.2	1.64

      2. Unconfined Compressive Strength Values for Red Mud Cement Mixes

         The samples of size 38 mm diameters and height of 76 mm were prepared by static compaction method to achieve maximum dry density at their optimum moisture contents. All the prepared samples were cured for 3 day, 7 day, 14 day and 28 day by maintaining 100% humidity.

         Cement (%)	UCS (kg/cm2)
         	Curing Period (days)
         	3	7	14	28
         5	23.0	46.15	67.94	78
         10	39	56.36	78.18	110
         15	48.59	60.56	76.68	142
         20	44	65.71	84.45	175

         TABLE 6 VALUES OF UCS FOR RED MUD CEMENT MIXES

      3. Split Tensile Strength

         The samples of size 38 mm diameters and height of 76 mm were prepared by static compaction method to achieve maximum dry densities at their optimum moisture contents. All the prepared samples were cured for 3day, 7 day, 14 day and 28 day by maintaining 100% humidity. The sample was loaded until splitting failure takes after completion of their required curing period at a strain rate of .25 mm/min.

         Tensile strength, St = 2Pu/ (DL)

         Where, Pu = ultimate load at which sample fails D = diameter of specimen in mm

         L = length of the sample in mm

         TABLE 7 VALUES OF SPLIT TENSILE STRENGTH FOR RED MUD

         CEMENT MIXES

   2. CONCLUSIONS

      • Red mud is a byproduct generated from production of aluminum which is highly alkaline in nature with high specific gravity with large amounts of silts.

      • Addition of cement to Red mud in various percentages (0, 5, 10, 15 & 20%) increases OMC values and decreases MDD values.

      • Increase in compressive strength for the red mud-cement mix was observed with increase in dosage as well as curing period.

      • Cement and Red mud mixture have changed the structure of Red mud into flocculated structure thereby increasing the strength of the mixture.

      • Increase in tensile strength for the red mud-cement mix was observed with increase in dosage as well as curing period.

      • Achievement of high strength values of Red mud-cement mixes can be effectively used in various geo technical applications.

1. REFERENCES

1. Manoj Bhaskar, Salim Akhtar, Geeta Batham, Development of the Bricks from Red Mud by Industrial Waste (Red Mud), International Journal of Emerging Science and Engineering (IJESE) ISSN: 23196378, Volume-2, Issue-4, February 2014.

2. Sawant.A.B, Kumthekar.M.B, Sawant.S.G, Utilization of Neutralized Red Mud (Industrial Waste) in Concrete International Journal of Inventive Engineering and Sciences (IJIES) ISSN: 23199598, Volume-1, pp 9-13, 2013.

3. T.D.V.Lakshmi,Dr. DSV Prasad, Dr. M Anjan, Dr.GVR Prasada Raju, Stabilization of Industrial Waste Red-Mud with Cement, International Journal of Research and Innovations in Earth Science Volume 2, Issue 1, ISSN (Online) : 2394-1375.

4. IS 2720 part 10 (UCS), IS 2720 part 16 (CBR) IS 2720 part 7 (light compaction).