Treated municipal wastewater to fulfil crop water footprints and irrigation demand – a review

Direct application of raw municipal wastewater for irrigation purposes may create many undesirable harmful consequences. Therefore, treated effluent through different technologies is generally preferred for reuse especially in water-scarce regions. In the present study, the performances of some treatment technologies like constructed wetland (CW), waste stabilisation pond (WSP), membrane bioreactor (MBR), vermi-biofiltration (VBF) and land treatment methods for removal of chemical and biological impurities from municipal wastewater were reviewed. The study revealed that the treated water quality varied depending on the hydraulic retention time under different treatment methods. The reservoir should be considered an integral part of the wastewater treatment system and not merely an operative ponding volume for irrigation. The comparatively advanced MBR technique showed better performance for removal of BOD, COD, fecal coliforms, Escherichia coli and other biological impurities than the traditional approach. Some techniques like land treatment methods and VBF were found to be equally attractive in developed as well as developing nations. The future projections of global green and blue water scarcities indicate treated water to be a valuable alternative water resource to fulfil required crop water footprints as well as irrigation demands.

Optimal treatment of agricultural land – special multi-depot vehicle routing problem

This paper describes a problem of optimal agricultural land treatment using aviation. The studied problem consists of determining the optimal routes for a given set of aircraft used for chemical treatment of arable agricultural land divided into parcels. This NP (nondeterministic polynomial time) problem is represented on a graph and a mixed integer mathematical programming model of the problem is formulated. This mathematical model is a specific variant of the multi-depot vehicle routing problem where a min-cost plan for the transportation of a homogeneous product (chemicals used for land treatment) from different supply locations (airfields) to different demand locations (agricultural parcels) should be generated. Some specifics of the agricultural land chemical treatment are described in the paper and the following specific conditions are taken into consideration: each parcel is treated only by one way of treatment and one aircraft; for each aircraft its chemical and fuel reservoir capacities are sufficient to serve its route. The complexity of the problem and the impossibility to obtain exact solutions for larger dimensions of the problem led to the formulation of a special heuristics which is presented in this paper. Numerical experiments are successfully conducted for larger problem dimensions and results are presented.

Potensi Inokulan Petrofilik dan Kompos Kotoran Ayam dalam Bioremediasi Limbah Minyak Bumi Sistem Land Treatment

Bioremediation of petroleum waste using the land treatment system is generally carried out by indigenous Petrophilic stimulation as a degrading agent. One of the efforts to improve the performance of the bioremediation system is by adding petrophilic inoculants and organic material as a source of nutrition. This experiment focused on observation of the effect of endogenous petrophilic consortium by adding chicken manure compost towards bioremediation performance parameters, including the efficiency of hydrocarbon degradation, soil pH and petrobacter population on Jatinangor Inceptisols contaminated with petroleum waste. The experiment Design used in this experiment was Factorial Randomized Block Design (FRBD). The first factor was the variation of the concentration of the petrophilic consortium, consisted of: (i) without a petrophilic consortium, (ii) the concentration of petrophilic consortium 1% (w/ w), (iii) the concentration of petrophilic consortium 3% (w/ w ), (iv) concentration of petrophilic consortium 5% (w/ w). The second factor was the variation of the concentration of chicken manure compost: (ii) without compost chicken manure, (ii) the concentration of chicken manure compost 1.5% (w / w), and (iii) the concentration of chicken manure compost 3% (w/w). ). The results showed that the treatment of exogenous Petrophilic and chicken manure could not significantly improve the biodegradation efficiency of hydrocarbons, but the Petrophilic additives of 3% (w/ w) could increase the highest Petrophilic population. From this study was found that indigenous petrophilic had the potential to degrade hydrocarbons by 71.20%, while the application of exogenous 1% (w/w) petrophilic was able to degrade hydrocarbons by 71.97 %.

Impact of Non-Agricultural Employment and Environmental Awareness on Farmers’ Willingness to Govern the Heavy Metal Pollution of Farmland: A Case Study of China

Heavy metal pollution of farmland is a significant issue affecting the quality of agricultural products and human health. Farmers’ behaviors can have a direct impact on the level of heavy metal pollution affecting farmland in China. Whether the heavy metal pollution of farmland can be effectively governed at a low cost depends on the farmers. This paper analyzes the mechanism by which the extent of non-agricultural employment and environmental awareness influences farmers’ willingness to govern the heavy metal pollution of farmland using microdata for farmers in China and conducts an empirical analysis via a logit model. The results show that farmers in China display low willingness to govern the heavy metal pollution of farmland and that the increase in non-agricultural income will not significantly improve this willingness. Environmental awareness and farmers’ willingness to govern the heavy metal pollution of farmland are closely related: the higher the environmental awareness of farmers is, the stronger their willingness to govern heavy metal pollution, and the higher the probability of their participating in fallow land treatment. The government can introduce incentives to improve farmers’ environmental awareness of the heavy metal pollution of farmland. In addition, the government should strengthen publicity about the positive effects of fallow land treatment and encourage farmers to participate in the governance of heavy metal pollution of farmland. Given increasing non-agricultural employment opportunities and the transformation of agricultural production modes, agricultural technical training provided by governmental departments can enable them to be more scientific and rational in their agrochemical selection and application, thus reducing or avoiding the heavy metal pollution of farmland at the source. Attention should be paid to the differences between farmers to ultimately reduce the cost and improve the efficiency of treatment.

Effect of Oily Sludge Land Treatment on Soil Conditions

Land treatment is a method of handling wastes produced by the petroleum refining industry and others. This method allows the simultaneous treatment and final disposal of the waste. This study represent a fundamental filed investigation to follow the land treatment method for disposing of an oily sludge produce by Daura Refinery Wastewater Treatment Plant. The sludge typically consists of (84.5-86.2)% water, (4.7-5.3)% oils, and (8.4-9.25)% sediments. It is characterized by law contents of phenol, nitrogen, and heavy metals of environmental concern. Loamy sand soil land located inside Daura Refinery was selected and divided into a1-sq. meter plots. A range of sludge application rates was applied to add the sludge to (mix with) the upper 15 cm soil layer of 18 plots, whereas 6 plots left as control plots. The applications range included three applications ratios of (fresh sludge wt, : dry soil wt.) as (1:3), (1:6), and (1:10), each of them was applied in three application intervals: weekly, monthly, and seasonally. Selection of the best application rate was made with regard to sludge degradation and land area requirements. Soil samples were tested for oil residue, heavy metals, total nitrogen, electrical conductivity, pH, and aggregate stability. The results show that, monthly (1:10) application rate caused neither considerable downward oil migration in the soil nor significant accumulation of oil, heavy metals, or salts in the soil. However, it maintained neutral soil pH and improved soil aggregate stability. Oil biodegradation in the soil was encouraged by soil weakly tillage.