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The paper aims to observe a continuous process industry, the cement manufacturing industry with the aim of identifying greening opportunities in its production operations. The study analyses areas pertaining to the cement industry that impact the environment with specific focus on the industry within a developing, lower income country.

A cleaner production (CP) approach was used in a case study approach, focussing on issues such as gaseous emissions and particulate emissions. Both capital intensive and less intensive options are proposed. Source reduction and pollution prevention operations that were used in this study include chemical substitution, technology modification and on-site reuse/recovery/recycling opportunities.

The paper provides insights about how change is brought about within a continuous process industry. It suggests that successful leaders act as “integrating forces” on two levels: integrating the elements of corporate identity structures and mediating between the corporate branding structures and the individual. Capital interventions included redesigning the clinker conveyor, as well as restructuring the dust transportation system. There is a need for the developing countries to track and identify modern interventions that are available within industry and adopt them.

The paper focusses on a single cement factory in a low income country, as the case study approach was used. As such, findings and options generated may not be generalized, as the processes from one industry to another tend to differ in different economies.

The paper includes implications for the development of greening manufacturing practices in the cement industry.

This paper fulfils an identified need to study how greening practices can be enabled and enhanced in a continuous manufacturing industry. The work informs greening practices at any level, with a focus of production experiences in the cement industry in a lower technology, developing economy that is less industrialized.

Since 1962 the world trades in bulk commodities as a whole have undergone two great changes: a large increase in the volume, and a large increase in the distance of the average route. In these years, trade in the five main dry bulk commodities doubled in tonnage, and in crude oil trebled in tonnage. During the same period, the length of the average route for the former rose from 3,400 miles to 4,650 miles, and for the latter from 4,500 miles to 6,750 miles. In short, three to five times as much ship capacity was required in 1973 as in 1962.

This paper offers a brief review of the present use of scanning electron microscopy (SEM) in concrete studies, from the perspective of how research in materials science is translated into applications in construction engineering. It describes the scope of present use of the method, and attempts a prospective for the near future in areas where more work could make productive use of the technology. Selected case studies have also been discussed. The electron microscope has been used as a research tool in understanding the root cause of the differing performance of various types of concrete under various conditions, a development tool in making better concrete, and a diagnosis tool on problems like cracking of concrete. The paper also explains how sample preparation affects the type and quality of information which the SEM can produce.

A try to find some useful applications for some products prepared from agricultural waste by mixing them with cement to act as reinforcement agents. The paper aims to discuss these issues.

Cement was mixed with microcrystalline cellulosic (MCC) fibres prepared from baggase, soaked in mixing water, followed by cubic pastes formation. The mixing was performed using different ratios of MCC; 0.5, 0.75, 1 and 3 per cent. The cement properties were followed at timed intervals, up to 90 days. The initial and final setting times of the pastes were determined. Bulk density, apparent porosity and compressive strength of the harden cement pastes were also identified. The hydration kinetic was followed by identifying free lime ratio and chemically combined water content. The structure of the hard cement pastes was followed by SEM, FTIR, DSC and XRD.

It was noticed that the weight of the prepared cement pastes using MCC was reduced, while the compressive strength was increased. In addition, lower ratios of MCC have shown better results at early ages of hydration and reported higher compressive strength than control. No interaction was reported between the fibres and cement constituents based on the performed analysis.

Different types of agricultural wastes can be compared in producing the best type of MCC for the same purpose of this research.

This piece of work has suggested a simple way to convert a product prepared from agricultural wastes in a small uniform size to a reinforcement agent to cement. Consuming this type of waste reduces the risks resulting from its burning at some countries such as Egypt.

MCC fibres have well-known binding properties and used successfully on wide range in medical applications for tablets production with low costs. These fibres have reduced the pastes weight and increased the compressive strength using low ratios of them. Moreover, there is no indication of a reaction between these fibres and cement constituents.

In transportation and distribution systems, the shipment decisions, fleet capacity, and storage capacity are interrelated in a complex way, especially when the authors take into account uncertainty of the demand rate and shipment lead time. While shipment planning is tactical or operational in nature, increasing storage capacity often requires top management’s authority. The purpose of this paper is to present a new method to integrate both operational and strategic decision parameters, namely shipment planning and storage capacity decision under uncertainty. The ultimate goal is to provide a near optimal solution that leads to a striking balance between the total logistics costs and product availability, critical in maritime logistics of bulk shipment of commodity items.

The authors use simulation as research method. The authors develop a simulation model to investigate the effects of various factors on costs and service levels of a distribution system. The model mimics the transportation and distribution problems of bulk cement in a major cement company in Indonesia consisting of a silo at the port of origin, two silos at two ports of destination, and a number of ships that transport the bulk cement. The authors develop a number of “what-if” scenarios by varying the storage capacity at the port of origin as well as at the ports of destinations, number of ships operated, operating hours of ports, and dispatching rules for the ships. Each scenario is evaluated in terms of costs and service level. A full factorial experiment has been conducted and analysis of variance has been used to analyze the results.

The results suggest that the number of ships deployed, silo capacity, working hours of ports, and the dispatching rules of ships significantly affect both total costs and service level. Interestingly, operating fewer ships enables the company to achieve almost the same service level and gaining substantial cost savings if constraints in other part of the system are alleviated, i.e., storage capacities and working hours of ports are extended.

Cost is a competitive factor for bulk items like cement, and thus the proposed scenarios could be implemented by the company to substantially reduce the transportation and distribution costs. Alleviating storage capacity constraint is obviously an idea that needs to be considered when optimizing shipment planning alone could not give significant improvements.

Existing research has so far focussed on the optimization of shipment planning/scheduling, and considers shipment planning/scheduling as the objective function while treating the storage capacity as constraints. The simulation model enables “what-if” analyses to be performed and has overcome the difficulties and impracticalities of analytical methods especially when the system incorporates stochastic variables exhibited in the case example. The use of efficient frontier analysis for analyzing the simulation results is a novel idea which has been proven to be effective in screening non-dominated solutions. This has provided the authors with near optimal solutions to trade-off logistics costs and service levels (availability), with minimal experimentation times.

This paper deals with the decision making about the strategic alternatives for distributing a commodity – the bulk cement – characterised by an extremely high incidence of the transportation costs. It is based on the case of Italcementi Group (ITC), the largest European producer of cement, leader in Italy with a share higher than 30 per cent and growing abroad through acquisitions and foreign direct investment in Europe, North America, Middle East and North Africa. This paper shows a methodology to select the most suitable alternative between own account, hire and reward and long‐term partnership to distribute basic commodities, given the existing manufacturing base (facility locations are given). The methodology takes into account the context of the local markets and supply of logistic services and considers multiple performance criteria.

The purpose of this paper is to investigate the effect of an admixture, Swine-waste Bio-char (SB), on the water absorption characteristics of cement pastes.

The effect of SB percentages, heat treatment temperatures, water/binder ratios, and age on the water absorption percentages (WAPs) of SB modified cement pastes were investigated using scanning electron microscopy-energy dispersive spectra, FTIR, Brunauer-Emmett-Teller, and laboratory experiments.

The WAPs of cement pastes with SBs produced at the low treatment temperature (LTT) of 340°C and 400°C were significantly lower (p<0.01) than pastes with SBs produced at the high treatment temperature (HTT) of 600°C and 800°C. This was attributed primarily to the more dominant presence of hydrophobic alkyl surface groups from non-volatilized matter in LTT-SBs. This had also resulted in lower surface areas and pore volumes in LTT-SBs. As a result of the volatilization of these labile hydrophobic groups at HTT, HTT-SBs were more hydrophilic and had higher surface areas and pore volumes. Consequently, HTT-SB pastes had higher WAPs and no significant differences (p<0.05) existed between HTT-SB pastes and control pastes. Also, low water/binder ratios and aging reduced water absorption of SB modified cement pastes.

LTT-SBs reduce water absorption and could reduce concrete deterioration; and as such, associated building repair, maintenance, and adaptation costs. Notably, reductions in concrete water absorption will extend the service life of concrete buildings and infrastructures, particularly in unfavorable environmental conditions. The observed benefits are tempered by the current lack of information on the effects of SB on compression strength, workability, and other durability properties.

SB utilization in concrete buildings will enhance swine-waste disposal and reduce negative environmental impacts on swine farming communities; consequently, improving their quality of life.

Current bio-char research is focused on plant-derived bio-char toward soil remediation and contaminant removal, with very limited applications in concrete. This research advances knowledge for developing livestock-derived bio-char, as a PCRM, toward more sustainable and durable concrete structures.

This study investigates the level of variance in the real time demand for bagged cement, induced in response to the climatic sequence of the humid tropics, to support best practice calls for a weather-responsive supply chain strategy.

Data on the consumption of cement and site works for 100 ongoing building construction sites were gathered for a period of 12 months. The variance partitioning capabilities of the Ordinary Least Squares and Hierarchical Linear Modelling forms of regression analysis are comparatively used to evaluate the sensitivity of cement demand to the meteorological profile of wet-humid climate

The study outcome provides statistical evidence demonstrating that the meteorological profile of wet-humid climate induces a significantly high percentage of the variance in the real-time demand for bagged cement on construction sites. However, nested within this variance, are the fixed effects of the cement footprint of the building architecture inherent in the locality. Particularly, positive changes to reduce the wet trade composition of buildings or compensating changes in technological bias, are necessary to combat weather interference in the humid tropics.

The findings are exploratory, and not for the purposes of holistically forecasting cement demand, and can therefore only form part of a more comprehensive decision support system, bespoke to the study area.

The study outcome provides a back-end view to climatic adaptation in wet humid settings, making a compelling case for localized climate-risk adaptive supply chain strategies and policies geared towards sustainability in cement usage.

The study delineates the confounding impact of weather, distinct from local building architecture and technological bias, thus creating a methodological platform for replication and comparative productivity studies in diverse geographical areas.

The purpose of this paper is to analyse two parameters relevant to the physical‐mechanical performance of external renders, mainly, bulk density and apparent or open porosity, by performing laboratory tests on samples collected under real in‐service conditions.

The test procedure (sample preparation and techniques used) and its relationship with the overall performance characteristics and with any anomalies are discussed for each parameter. The analysis of the results covers seven case studies and 15 walls with renders made on site (cementitious and cement‐lime based) and non‐traditional or pre‐mixed renders.

It was concluded that reliable relationships could be established between the test results and other physical parameters relevant to the mechanical and water‐related behaviour of different types of cementitious renders. Notwithstanding the usual drawbacks of laboratory tests (more time‐consuming, higher costs and greater destruction of the walls), the use of small samples and the additional data obtained in terms of in‐service performance justify the use of this type of test.

The originality of this approach comes from the advantage of conducting both laboratory tests (reliability and standardization) and in situ tests (testing real materials subjected to in‐service conditions). Current practice is either to test virgin materials in quasi‐perfect laboratory conditions (therefore far from reality) or to test materials on site using standard in situ techniques sensitive to subjectivity and in far from ideal environmental conditions.

To develop just‐in‐time (JIT) purchasing threshold value (JPTV) models for ready mixed concrete (RMC) suppliers to decide whether or not to switch from an economic order quantity (EOQ) approach to a JIT purchasing approach for the purchase of their raw materials, when a price discount is offered.

The existing economic order quantity (EOQ) with a price discount versus the JIT purchasing cost comparative models neglect some important cost components under the inventory management systems, for example, the out‐of‐stock costs and the impact of inventory policy on product quality and production flexibility. In addition, these models do not empirically study the capability of an inventory facility to hold the EOQ‐JIT cost indifference point's amount of inventory. These models suggest that the JIT purchasing approach is always preferred to the EOQ approach when the JIT purchasing approach can capitalize on physical plant space reduction. The JPTV models developed in this study overcome the two limitations of the existing EOQ and JIT purchasing cost comparative models.

By developing the JPTV models, this study suggests that the theoretical advantages of JIT purchasing may have been overstated.

The field studies conducted in the RMC industries in Chongqing, China and Singapore supported the propositions in this study. The JPTV models, if adopted, would help to enhance performance in the RMC industries in other cities as well.