During the production of one ton of Ordinary Portland Cement (OPC), an equal quantity of carbon dioxide is released into the atmosphere which is destructive to our environment. So, there is a need to choose an alternative, in order to

Hypo Sludge adds advantageous properties to the concrete and helps to maintain low-cost. Numerous researchers have concentrated on the application of hypo sludge in concrete and cement production to achieve ecological conservation. Many studies have been carried out to check for the feasibility of implementing the hypo sludge in concrete production as fractional replacement of cement. The usage of hypo sludge in concrete can reduce the paper industry waste removal costs and thus develop a green concrete for the structure

Balwaik et al. (2011) made a study on the application of paper mill waste in cement

This study mainly focuses on the use of hypo sludge paper mill waste as a partial replacement of cement. The rate analysis was also done in order to show the cost effectiveness of the usage of waste and effective material in concrete. Usage of paper mill waste also reduces the carbon dioxide emission into the atmosphere, thus reducing the production of cement. Further, the quadratic polynomial equation was also developed.

In this research, Ordinary Portland Cement (OPC) of 53 grade, coarse aggregate, fine aggregate and super plasticizer were used. Hypo sludge from the Seshasayee paper and Boards limited, Erode was collected and used. Hypo sludge was used in the constituents of 20%, 30%, 40% and 50% as replacement in cement. Mix design was done for M30 according to IS 10262

Sl.No | Material | Properties | Value |
---|---|---|---|

1 | Cement | Specific Gravity | 3.15 |

2 | Fine Aggregate | Specific Gravity | 2.66 |

3 | Fine Aggregate | Grading of sand | Zone III |

4 | Coarse Aggregate | Specific Gravity | 2.94 |

Hypo Sludge has more alike elements of cement such as lime, silica, alumina, magnesium, etc. The comparison between the properties of cement and hypo sludge

Sl.No | Constituent | Cement (%) | Hypo Sludge (%) |
---|---|---|---|

1 | Lime | 62.00 | 46.20 |

2 | Silica | 22.00 | 9.00 |

3 | Alumina | 5.00 | 3.60 |

4 | Magnesium | 1.00 | 3.00 |

When hypo sludge is partially replaced in cement, the initial and final setting time varies according to the percentage replaced. Initial and final setting time was done according to IS 4031(Part 5):1988

Sl.No | Constituents | Initial setting time (min) | Final setting time (min) |
---|---|---|---|

1 | Cement with 0% hypo sludge | 31 | 602 |

2 | Cement with 20% hypo sludge | 32 | 599 |

3 | Cement with 30% hypo sludge | 33 | 598 |

4 | Cement with 40% hypo sludge | 34 | 596 |

5 | Cement with 50% hypo sludge | 35 | 595 |

Compressive strength was done according to IS 516 (1959)

f_{ck} =

Where, f_{ck} is the compressive strength of concrete, P is the compressive load and A is the cross sectional area.

The 7 days compressive strength were 22.60 MPa, 26.40 MPa, 21.80 MPa, 19.90 MPa and 16.20 MPa for 0%, 20%, 30%, 40% and 50% of hypo sludge replacement of cement respectively. The 28 days compressive strength were 34.80 MPa, 36.20 MPa, 32.40 MPa, 28.90 MPa and 26.40 MPa for 0%, 20%, 30%, 40% and 50% of hypo sludge replacement of cement respectively.

Cost analysis was performed for the partial replacement of hypo sludge in concrete. Rate analysis for partially replaced hypo sludge in cement was illustrated in

Cement (Kg/m3) | Cement cost (Rs) | Hypo sludge (%) | Hypo Sludge (Kg/m3) | Hypo sludge Cost (Rs) | Total cost (Rs) |

320 | 2048 | 0 | 0 | 0 | 2048 |

256 | 1638 | 20 | 64 | 32 | 1670 |

224 | 1433 | 30 | 96 | 48 | 1481 |

192 | 1228 | 40 | 128 | 64 | 1352 |

160 | 1024 | 50 | 160 | 80 | 1104 |

Cost of cement per bag (50 Kg) = Rs.320.00. Cost of cement per kg = Rs. 6.40.

Price of hypo-sludge per kg = Rs.0.50. Cost of cement per m3 = Rs.320.

Cost fine aggregate per m3 = Rs. 764.00. Cost fine aggregate per m3 = Rs. 1260.00.

The prediction model was developed using the quadratic response surface equation which is as follows:

Where y signifies response or target function, X_{i }signifies the independent variable, β_{i}, β_{ii}, β_{ij} signifies the coefficients of regressions for the first, second and cross degrees, and k signifies the factor of an effective amount and e indicates the error _{ck}) was preferred as the responses. Hypo sludge replacement (A) and curing age (B) were considered as the factors influencing the responses

The quadratic polynomial equation has been proposed for the compressive strength using RSM:

f_{ck} = 9.89+(0.35xA) +(2.22xB) -(1.90x10^{-3}xAxB) - (9.50x10-3xA2) -(0.04xB2) (eq.3)

‘f_{ck}’‘A’‘B’the curing days in nos.

Based on the concrete compressive strength experimental study, the subsequent annotations are made concerning the resistance of partly replaced hypo-sludge. In this study, maximum compressive strength was found at 20% replacement of hypo- sludge in cement. The compressive strength starts decreasing at 30% and above. Thus, in this study, 20% replacement of hypo-sludge in cement were found to be efficient compared to other proportions. The cost of 20% replacement of hypo sludge in cement (kg/m3) is Rs. 1670.00, whereas for normal cement (kg/m3) is Rs. 2048.00. Environmental effects from wastes and the maximum amount of cement manufacturing are reduced through this study. In this study, the quadratic polynomial equation has also been proposed.

Cement production creates a lot of pollution problems and unwanted environmental hazards, which in turn affects mankind. In order to reduce the pollution problems, the production of cement has to be reduced. This study thus aimed at reducing the production of Cement. Hypo sludge from Paper mill industry has more similar properties to Cement. Thus, it has been utilized as replacement material in Cement. In this study, 20%, 30%, 40% and 50% of cement using hypo sludge was done. The cost analysis study was also been done for the same. Among which, 20% replacement of hypo sludge in cement was found effective in strength. When the percentage variation exceeds 20%, there is strength reduction. Hence, it is efficient to replace hypo sludge of up to 20% into cement.