Revealing Patterns in the Aggregation and Deposition Kinetics of the Solid Phase in Drilling Wastewater

We have investigated the influence of the concentration of the solid phase of drilling wastewater on a change in the sedimentation rate of the solid phase at aggregation when applying a physical-chemical method of water purification using flocculants and coagulants. This is important because a change in the concentration of the solid phase in wastewater is an uncontrolled process during reagent-based purification and it significantly affects the aggregation mechanism, as well as the kinetics of a solid phase sedimentation.The study was performed using the model wastewater prepared by diluting the used drilling mud with tap water. It was found that the use of flocculants without coagulants is not effective and does not lead to aggregation. It was established that the optimum dose of the coagulant aluminum sulfate that is capable of disrupting the stability of the disperse system of drilling wastewater is 65 mg/g, while increasing the dosage of coagulant has no effect on the rate of flake deposition. Among the flocculants, the most active one is the anionic flocculant A-19. Sludge thickening results in the destruction of floccules; in 9 minutes, the floccule deposition rate is reduced two-fold. Increasing the concentration of a flocculant from 0.8 mg/g to 1.6 mg/g leads to an increase in the deposition rate of the solid phase by 2‒2.5 times.It is shown that the solid phase concentration affects the sedimentation rate of floccules; optimum conditions for aggregation are observed at a concentration of 4‒6 g/l. Mechanical impacts on aggregates exert a destructive effect depending on the concentration of the solid phase. It has been established that changes in the dispersed system can be observed based on a change in pH, which varies depending on the concentration of the solid phase in drilling wastewater. Increasing the concentration of the solid phase from 1 to 10 g/l leads to the change in pH from 7.2 to 8.3; the introduction of coagulant reduces pH, while the subsequent destruction of aggregates leads to an increase in pH. The data obtained in the course of our research, as well as the proposed procedure, could be used in order to select the optimal dosages of reagents during drilling wastewater treatmen

Studying Patterns in the Flocculation of Sludges From Wet Gas Treatment in Metallurgical Production

The influence of a solid phase concentration in the model sludges of wet gas purification, as well as the flocculant consumption, on a change in the solid phase sedimentation rate and the strength of floccules has been examined. This is important because fluctuations in the solid phase concentration in waste water represent an uncontrolled process that significantly affects the kinetics of the solid phase sedimentation and leads to an increase in the flocculant consumption.We have proposed a procedure for determining the sedimentation rate of the flocculated sludge and the strength of floccules following the hydromechanical influence, which takes into consideration the solid phase concentration and the flocculant consumption. The study was carried out on model waste water, synthesized by mixing the dust from dry gas purification at actual production site with water. It has been determined that the solid phase concentration affects the rate of floccule deposition. It has been established that the optimum conditions for aggregate formation within a given model system are observed at the solid phase concentration in the interval 8–12 g/l. Increasing the solid phase concentration above 16 g/l decreases the floccule sedimentation rate disproportionately to the flocculant concentration. It is possible to reduce flocculant consumption and to optimize its dosage by carrying out a cleaning process taking into consideration the specified patterns.It was established that the hydromechanical influence on aggregates exerts the destructive effect, whose degree depends on the solid phase concentration. In particular, increasing the rate of fluid motion leads to greater damage to floccules than increasing the time for a less intense exposure. The way to minimize the destructive effect on floccules could be lowering the suspension transportation speed resulting from a decrease in the installation performance or through the increased cross-section of the channel (a pipeline). An increase in the solid phase concentration of the model system above 16 g/l is accompanied by a significant reduction in the strength of floccules. Therefore, when designing wastewater treatment plants that utilize flocculants, it is necessary to provide optimum conditions for aggregation and to minimize the hydromechanical effects on floccules by lowering the velocity of fluid motio

Identification of Properties of Recycled High­density Polyethylene Composites When Filled with Waste Mud Solids

The possibility of increasing recycling volumes of drilling waste using as a filler for producing polymer composites is considered. As a result of the research, modification of recycled high-density polyethylene with waste mud in the form of fine filler particles is carried out.Recycled high-density polyethylene polymer composites, filled with drilling waste with a content up to 30 % are obtained. As a result of the study, regularities of changes in impact strength, ultimate bending and water absorption, depending on the waste mud solids (WMS) content in the recycled polymer are found.It is shown that the introduction of WMS in the form of fine filler particles in recycled high-density polyethylene significantly increases their strength characteristics without a substantial deterioration in water absorption (up to 2.9 % when filled with waste up to 30 %).It is found that the optimum content of drilling waste in recycled high-density polyethylene polymer composites is 20 wt %. At the same time, the maximum values of impact strength and ultimate bending are achieved for the composite with bentonite clay WMS up to 63.3 kJ/m2 and 200.1 MPa, and for the composite with salt WMS up to 38.1 kJ/m2 and 207.4 MPa, respectively. The resulting polymer composites outperform the known similar polymers with the use of such fillers as talc and kaolin. This allows recommending joint recycling of drilling and polymer wast

Identifying the Properties of Epoxy Composites Filled with the Solid Phase of Wastes From Metal Enterprises

The article addresses the issue related to the disposal of dust from steel industry as a reinforcing filler for epoxy composites. The polymer composition of "cold welding" that has been developed and studied includes epoxy dian oligomer, amine hardener and the filler – finely dispersed waste of metals. Polyethylene polyamine was used as a hardener in order to improve heat resistance and strength characteristics. Manganese triacetate was used in order to decrease the temperature and reduce the time of curing.The possibility was established to dispose of finely dispersed metal-containing waste from metallurgical production to be used a filler for epoxy composites of cold curing. It was revealed that the optimal content of dusts from foundries in the composite is at the level of 45–60 %. At this content, there is the highest impact resistance at the level of 40–50 MPa and a softening temperature in the range of 170–190 °С. It was established that at an increase in the amount of a filler from 40 % to 70 %, the cross-linking degree increases by 88 % to 98 %, respectively. However, at the content of the filler less than 45 % or exceeding 60 %, the impact resistance of the resulting composites decreases. At the content of a filler in the composite less than 45 %, the cause of low values of impact resistance and softening temperature could be the low cross-linking degree, less than 90 %. A decrease in these properties of composites at the content of the filler exceeding 60 % could be associated with the formation of a heterogeneous structure of filler. In the compositions with the highest performance characteristics, there is an optimized content of the filler and catalyst. Using a hardener and a curing catalyst in quantities of 3–3.5 and 1.5–2 %, respectively, makes it possible to shorten curing time by up to 2 hours. In general, the resulting epoxy composites are superior in their performance to known cold-curing analogs.The dependences of impact resistance, softening temperature, and cross-linking degree on the content of waste in the composite were derived, which make it possible to calculate the optimal formulation for composites depending on the required propertie

Establishing the Regularities in Forming the Properties of Ceramic Wall Materials Containing Waste From Gas Extraction (Drilling Sludge)

This paper addresses the prospects of recycling waste from oil and gas extraction in order to manufacture building materials. The principal possibility has been established to apply the examined samples of drilling sludge as the basic raw material and a mineral additive in the compositions of masses to produce wall ceramics with the required consumer properties.The main technological parameters for obtaining wall ceramics using the samples of gas extraction waste have been investigated. The formulations for ceramic masses have been developed applying fusible medium-sintered loam and drilling sludge in the amount of 20–80 % by weight. The properties of the obtained ceramic samples containing clay and high-carbonate drilling sludges have been analyzed. It has been found that increasing the amount of drilling sludge in the samples by 20 % to 80 % leads to a decrease in the density, strength, and an increase in the water absorption of the samples, which affects the quality of ceramics and the possibility of its practical use. We have established the regularities of change in the properties of the wall materials samples depending on the amount of the examined drilling sludge.The optimal number of drilling sludge samples for the manufacture of wall ceramics with the norm-compliant properties has been determined. It has been found that it is possible to use clay drilling sludge (20‒80 %) in the composition with fusible loam in order to obtain frost-resistant ceramic materials whose water absorption is at the level of 12 %, of grade M 125‒M 175. Adding high carbonate sludge to fusible loam in the amount of 20 % makes it possible to receive frost-resistant ceramic materials of grade M 75, in the amount of 40 % ‒ of grade M 10