The cement industry is one of the most polluting industries globally, due to the high amount of CO2 emissions generated during production. Improving the sustainability of cement production is thus vital. Waste paper is also a big problem for many societies, especially in developed countries, where the use of board and paper increases almost every day. This work examines the possibility of using incinerated waste paper ash (IWPA) and non-incinerated waste paper (NIWP) as a partial replacement for cement (by weight) in mortar mixtures. For non-incinerated waste paper, the tested replacement levels were 1%, 1.5%, 2.5% and 3.5%, while for incinerated waste paper, the replacement levels were 2.5%, 5%, 7.5%, and 10%. An additional mix without any replacement was also cast for comparison purposes. The fresh and hardened properties of mortar were assessed using flow rate, compressive strength, direct tensile strength, water absorption, and dry density tests, and two test ages (7 and 28 days) were considered for the compressive and tensile strength tests, though water absorption and density tests were undertaken at 28 days only. The results showed that the presence of waste paper (incinerated or non-incinerated) reduced the flow rate of fresh mortar as compared with the reference mix. It was also found that, for the NIWP mixtures, 1% replacement of cement was the most efficient percentage; this increased the compressive strength by 16% and the direct tensile strength by 19% at 28 days of age. For the IWPA mixes, the results showed that the best replacement ratio was 5%, where the compressive strength and direct tensile strength were improved by 10% and 11% at 28 days, respectively. These 1% NIWP and 5% IWPA mixtures gave similar water absorption of 7% to the reference mix.

Waste incineration (WI) is the most popular method of hospital waste (HW) disposal in many developing countries. Most hospitals generate large quantities of toxic and persistent waste, which are managed by burning in incinerators. Basically, high concentrations of heavy metal in the food chain are generated from ash residue after burning process. As a result, these concentrations lead to harmful effects on the public health as well as environment. This study aims to investigate the concentrations of heavy metal in the ash of incinerated waste HW1 and HW2 that generated in two hospitals at Samawah and Rumaitha cities, respectively. Ash samples were collected within three months from medium and small incinerators. The concentrations of Cd, Cr, Cu, Pb, Fe and Zn metals were measured using Atomic Absorption Spectrometer (AAS). The concentrations of heavy metal were sorted in descending order as follows: Fe, Zn, Ni, Cu, Pb, Cr and Cd. For both hospital waste, the Fe level was ranged between 76.6 and 25.3 μg/g while other metal levels were varied as follows: Cd (4.6-1.4 μg/g), Zn (35.6-5.6 μg/g) and Cu (17.2-4.0 μg/g). The concentration of Pb in HW2 was found relatively higher than in HW1. The concentration of Pb was varied as (21.6-7.5 μg/g) in HW2 and (15.6-5.4 μg/g) in HW1. Whereas the Cr and Ni concentrations were found as (14.7-1.1 μg/g) and (6.717-3.3 μg/g) in HW1 and HW2, respectively. According to the EPA Law, the concentrations of all samples exceeded the maximum permissible heavy metal levels and can be classified as toxic and risky levels.

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Fine aggregate considered as the oldest building materials known by human, it's not inert substance, so that each of its physical and chemical properties need theoretical and laboratory studies, because, of its effect on the compressive strength and durability of concrete, one of the most important properties is the content of sulphate salts, which must be taken into account in all construction works. This research aims to conduct laboratory qualitative assessment of fine aggregate to demonstrate its suitability for construction work and quality assurance. Sampling of fine aggregate (sand) from four quarries in Al-Najaf Alashraf [(Syd Ali (S1), Wilaya Ali (S2), Syd Ahmed (S3) and Muhand Al-Khiat (S4)]. Some of physical tests (sieve analysis, deleterious materials (clay%), bulk density, specific gravity and absorption), chemical analysis for sulphate salts content, X-Ray technology for mineral composition as well as the compressive strength test were conducted on these samples. From the results of this research, its appear that Sample Wilaya Ali (S2) is the best for concrete works where the grading and sulphate salts content (SO3) is accepted by (IQS), and this sample gives accepted compressive strength. While Sample Syd Ali (S1) was the most fine with accepted sulphate salts content as compared with (IQS) which make it suitable for other construction works rather than concrete. Samples, Syd Ahmed (S3) and Muhand Al-Khiat (S4) are of high sulphate salts content (which cannot be treated) as compared with (IQS) which make them not compatible for concrete and other construction works.