Industrial Waste Stabilization Research Articles

Environmental Friendly Lightweight Artificial Aggregates through Industrial Waste Stabilization

The production of lightweight artificial aggregates proposed in this study derives from industrial waste recovery activities, such as fly ash (FA) and ground granulated blast furnace slag. The aim is to reduce the compromise of the environment and human health, through the recycling of special waste. The use of inert aggregates from recovery from industrial waste encourages the reduction of soil consumption, the waste of natural aggregates, consequently limiting the consumption of waste materials from quarries, as well as facilitating the recovery of waste that would inevitably end up in landfilled or abandoned in the environment. Specifically, in the present work, the lightweight artificial aggregates were produced by cold bonding granulation technique. All the mixtures, made by 80% of FA with various composition of cement and granulated blast furnace slag, were characterized by density values ranging from 1.63 to 1.66 g cm-3 suggesting their suitable classification as lightweight aggregates (LWAs). Water absorption capacity (WAC) and open porosity values decreased with the increase of the percentage in cement. The impact test results indicate that all the aggregates have proved to be suitable as filling for road pavements. The best crushing strength values (1.86 MPa) were observed for the mixture contain the highest amount of cement. Aggregate leaching tests indicated a significant release of chlorides and sulphates while the release of heavy metals was lower than the limits set by the standard UNI 10802.

Characterization, classification and stabilization of industrial wastes for hazard property HP3: Flammable self-heating; assessment and evaluation of 50 industrial wastes

A pilot assessment procedure is introduced and used for the self-heating behavior of 50 industrial wastes based on UN N. 4 test and their subsequent classification as hazardous or non-hazardous, according to the Waste Framework Directive (WFD). When a waste contains self-heating substances it is classified as ‘Hazardous Waste’ by hazard property HP3: Flammable according to Regulation (EU) No 1357/2014. Self-heating is considered as a precursor stage to spontaneous ignition and fire under certain circumstances, with environmental effects and both human and property losses. The influence of the following parameters on the self-heating nature of the industrials wastes was assessed: temperature, granulometry and moisture. It was demonstrated that although some wastes are classified as absolute non-hazardous (ANH), they may still exhibit self-heating and thus must be classified as hazardous by HP3. It seems that there is a gap between the definition of hazardous waste according to WFD and the entry type of List of Wastes (LoW), regarding the ANH entries. This was found to be the case with two of the wastes examined. Finally, for a waste exhibiting self-heating, experiments were performed with addition of inert material, in order to secure safe management of the waste.

Prediction of Unconfined Compressive Strength of a Stabilised Expansive Clay Soil using ANN and Regression Analysis (SPSS)

Industrial waste stabilization is one of the common techniques used to improve the strength of weak soils as it is very difficult to find suitable soil everywhere for foundation. The strength developed by this stabilization technique depends on percentage addition of additives, soil properties and curing period. In order to reduce the time consuming process of laboratory investigation and for effective utilization of industrial waste additives, a mathematical model is developed relating the gain in strength (UCS) with the variables responsible. In this study, Artificial Neural Network (ANN) and Regression analysis (SPSS) is used for prediction of unconfined compressive strength (UCS) of clay stabilized with industrial waste namely bottom ash and Ecosand. The predictor variables used for developing the models are Curing Period, Bottom Ash and Ecosand dosages, Liquid Limit (LL), Plasticity Index (IP), and Free Swell. Based on laboratory investigations, the data's are divided into three groups based on the additives added. Regression analysis and artificial neural networks prediction showed that acceptable correlations exist between soil properties and unconfined compression strength of the stabilized clay soil. Based on analysis, artificial neural network (R2=0.978) showed closer prediction results when compared to the regression analysis (R2=0.939).

Investigation of biocatalytic potential of garbage enzyme and its influence on stabilization of industrial waste activated sludge

The decomposable waste thrown into the environment can be used to produce value added bio-product which in turn reduces the production of greenhouse gas. Garbage enzyme is one such value added product produced by fermentation of organic solid waste. In the present study enzyme activity and disinfectant potential of garbage enzyme was evaluated and its influence on reduction of total solids, suspended solids and pathogens in dairy waste activated sludge were studied. The result showed the garbage enzyme possesses protease, amylase and lipase activity and reduced 37.2% of total solids, 38.6% of suspended solids and 99% of pathogens in dairy waste activated sludge. This significant result may be helpful for researchers to compare the effectiveness of earth-friendly garbage enzyme treatment of industrial sludge with various physical and chemical pre-treatment methods to improve the biogas production from the sludge digestion unit.

TiO2-coated EP as a floating photocatalyst for water purification

A water-floating photocatalyst composed of TiO2 deposited on perlite granules was synthesized and characterized. TiO2 was deposited by direct precipitation of titanium(IV) isopropoxide in the presence of perlite granules followed by calcination at three different temperatures. Temperature induced structural changes were monitored using UV-Vis, infrared and Raman spectroscopy, powder X-ray diffraction, BET surface adsorption, and scanning electron microscopy. The photocatalytic activity of the obtained materials was determined using a model reaction of the oxidative degradation of phenol. The ability of the obtained photocatalyst to float, combined with its ability to absorb solar light, makes it particularly well suited for the purification of shallow water reservoirs and industrial waste stabilization ponds.

Dynamics of industrial waste stabilization pond treatment process

Waste stabilization pond is an artificial ecosystem; its performance is governed by the nature of the biological communities it supports. These are primarily used as secondary effluent treatment plants to polish the effluents. However, they are also used to treat the raw sewage and industrial effluents. In the present study, the functioning of a waste stabilization pond system from an industrial complex located in Goa was taken up. The raw waste released by the industrial complex and the final effluent released from the stabilization ponds were analyzed for pH, dissolved oxygen (DO), biological oxygen demand, phosphate content, chlorophyll content, and algal diversity and density. Also, the activities of the enzymes catalase and phosphatase were measured. The study was carried out for a period of 1 year and the data covering pre-monsoon, monsoon, and post-monsoon seasons are tabulated. The study revealed that DO, chlorophyll content, and algal count were maximum during pre-monsoon when compared to monsoon and post-monsoon. Similarly, maximum enzymatic activity was recorded during pre-monsoon and also maximum removal of biological oxygen demand and phosphate was recorded during this period than in monsoon and post-monsoon.

Hazardous industrial waste stabilization using inorganic phosphates: Investigation of possible mechanisms

Abstract The present study focuses on the use of phosphate-containing compounds, such as apatites, as stabilization additives for solid industrial wastes. The examined highly toxic waste contained mainly lead, iron, and bromides. Phosphates (synthetic or natural), when used as additives, were found to diminish the release of lead from the stabilized waste below the respective legislative concentration limits, following the application of DIN 38414 standard leaching method and within the range of pH values 7.5-10.5. The respective synthetic compounds of lead, PbO and Pb(OH)Br, existing also in the solid waste, were additionally studied during simulation experiments, in order to examine the possible mechanisms of waste stabilization, by using the same additives (phosphates). The obtained results showed the possibility of another parallel mechanism, different from that proposed in the literature, which is the sorption of aqueous lead ions onto the apatite surface. It was suggested that lead can be also transformed into the less soluble solid phases through the interaction (surface crystallization) of exposed lead surface with the aqueous environment. The formation of new crystals onto the surface of lead phase was sufficiently fast, especially in the case of natural phosphate mineral additive, most probably due to the presence of calcite, which supplies part of its carbonate content for the formation of respective lead carbonate solid phases.

Solidification/stabilization of industrial wastes using polyurethanes

The results of solidification and stabilization of industrial wastes (metallurgical slag, lead smelting slag, flotation waste, scale), from various Polish factories, with using a polyurethane binder based on PMDI and one of following components containing OH groups: Rokopol G-1000, Terate 203 or water are reported. The effects of the type of a binder and its content as well as the type of waste on the density, hardness and compression strength of moldings of utilized wastes were investigated. It was stated that the type of a binder does not influence the properties investigated at a small range of binder content (up to 5.0 wt. %). From the economical point of view, using the PMDI/H 2 O system as a binder is the most justified.

Innovative management of an Aerated/Facultative Lagoon suspended—growth biological treatment system for high strength industrial waste stabilization

AbstractCoors Bio Technology Products Company, in Johnstown, CO is a subsidiary company of Adolph Coors Brewery Company in Golden, CO. Coors BioTech is a corn wet–milling industrial plant which processes shelled corn and converts it into several basic economical products: high fructose corn syrup (HFCS), corn oils, starch, sugars, and various agricultural by–products (Figure 1). The corn wet–milling operation and HFCS refining process generates a continual discharge of numerous process wastes. This wastewater is characterized as being a high strength, soluble, biodegradable waste, highly variable in composition. Coors BioTech treats their own industrial waste on site at their wastewater treatment plant using the activated sludge process. The objective of this paper is to provide a more complete understanding of the necessity for innovative management of the Aerated/Facultative Lagoon in the Coors BioTech waste treatment process, and suggest the applications of such lagoons in secondary biological treatment systems for high strength industrial waste stabilization [1–5].

Determination of Cellosolve and Chlorex Concentrations Inhibitory to Industrial Waste Stabilization Pond Treatment Efficiencies

Determination of Cellosolve and Chlorex Concentrations Inhibitory to Industrial Waste Stabilization Pond Treatment Efficiencies

Assessing microbial toxicity of 2‐ethoxyethanol and BIS (2‐chloroethyl) ether by a modified spread plate method

Abstract Microbial populations indigenous to three industrial waste stabilization pond influents were assayed using the two organics separately and in combination. Individually, the LC50 values were 17,400 mgl−1 for 2‐ethoxyethanol and 2,160 mgl−1 for bis(2‐chloroethyl)ether. The growth inhibition of heterotrophic microorganisms exposed to combinations of the two organics could be accurately predicted by a multiplicative survival model based on individual exposures to the two organics. No synergism or antagonism was observed.

Feasibility of two‐phase anaerobic stabilization of industrial waste with simultaneous production of energy

Abstract Single‐stage high‐rate (or conventional) anaerobic digestion of soft‐drink bottling waste exhibited unbalanced acidogenic and methanogenic fermentations at HRT's below 10 days and loading rates above 2 kg VS m‐3 day‐1. By comparison, the two‐phase digestion process was operated at much higher loading rates and much lower HRT's to afford the same methane yield and COD reduction efficiency as those of the conventional process. The economic advantages of the two‐phase process were that for this waste the digester volume could be reduced by more than 67% and the net energy production increased by more than 73% compared with those of the conventional process.