Waste Brine Research Articles

Experimental analysis of R134a working fluid on Organic Rankine Cycle (ORC) systems with scroll-expander

Waste Heat Recovery System (WHRS) technology, e.g., Organic Rankine Cycle (ORC) has been explored as a solution to the increase in geothermal potential, possibly applied in binary or combined form, as a single-flash plant. This approach utilizes waste brine obtained from the separator. The purpose of this study, therefore, was to determine the performance of R134a refrigerant on ORC systems, using scroll-expander. The experiment was conducted with motor different frequency, at 7.5 Hz, 10 Hz, 12.5 Hz, 15 Hz, 17.5 Hz, and 20 Hz, evaporator temperature regulation of 95 °C, condenser at 10 °C, and an initial working fluid pressure of 5 bar. The results showed modifications in the ORC system performance with scroll-expander, alongside the motor frequency, which influenced the net power and energy efficiency. In addition, the maximum speed produced by the expander was 505.8 rpm, while the highest for energy efficiency achieved from the system was 3.17%, at a motor frequency of 7.5 Hz, with a resulting net power of 584.5 Watt.

Pilot Plant Study to Utilize Waste Brine Generated by Salt Industries

Since early 80s, people of Pakistan have been enjoying good quality of salt known as refined salt. Mechanical salt washing is used in many countries to upgrade salt quality. The counter current washing at multiple stages and dewatering by centrifuge improves salt quality. During this process almost 10 to 15% of salt is converted into saturated brine solution containing high amount of sodium chloride, calcium, magnesium, potassium and sulphate. In the current practice most of the salt processers, this brine waste solution is drained. In the present study, a method is modified to utilize this waste brine solution. Brine was treated with calcium oxide and iron chloride to remove some soluble and insoluble impurities. The treated brine is evaporated in a specially constructed jacketed crystallizer connected with a hot water geyser. Heat is transferred through bottom by counter current flow. The temperature is maintained between 55 to 65oC at pH 3-4. The applied study yield the well shaped pyramidal crystals of salt known as Fluer de sel (flower of salt), that are world famous and used in gourmet foods with a growing market. Fleur de Sel has unique morphology, lower bulk density, large surface area, improved taste and rapid dissolution as compared to the common cubic salt

Synthesis of Sustainable Carbon Negative Eco-Industrial Parks

Growing climate change concerns in recent years have led to an increased need for carbon dioxide emission reduction. This can be achieved by implementing the concept of circular economy, which promotes the practice of resource conservation, emission minimization, and the maintenance of sustainable revenue streams. A considerable amount of carbon dioxide emissions is a consequence of stationary sources from industrial processes. These emissions can be reduced using carbon capture utilization and storage (CCUS) or reduced at source by using emission free renewable resources. The method developed within this work uses mixed integer linear programming (MILP) to design sustainable clusters that convert seawater (including waste brine), air, and waste carbon dioxide emissions to value-added products with sunlight as the main energy source. In this way, circular economy is employed to minimize fresh resource consumption and maximize material reuse. The potential of this work is demonstrated through a case study, which shows that an industrial park may be profitable while adhering to strict emission and material constraints.

High purity recovery of magnesium and calcium hydroxides from waste brines

Direct disposal of concentrate brines, generated by many industrial sectors, causes serious environmental concerns. An industrial sector that produces high concentrate brines is softening water industry, in particular during the regeneration of ion exchange resins. These brines are mainly rich in sodium, magnesium and calcium chlorides, thus, their regeneration, by removal/recovery of magnesium and calcium, can be a valuable option to turn the brine into a source of minerals and reduce disposal costs and environmental concerns. In this regards, one of the goals of EU-funded ZERO BRINE project is to develop a treatment chain for the valorization and regeneration of spent brines from water softening plants. The treatment chain consists of Nanofiltration, crystalization and evaporation to regenerate spent brines and recover high purity magnesium and calcium hydroxides. In this work, a wide experimental campaign was carried out to recover high purity magnesium and calcium via selective chemical precipitation of relevant hydroxides adding by injection of an alkaline solution in two consecutive steps at controlled pH. Precipitations were performed using synthetic brine solution, mimicking the retentate produced by nanofiltration, some of them were carried out considering a pre-treatment step to remove bicarbonate ions.

Sulfate precipitation treatment for NOM-rich ion exchange brines

Ion exchange (IEX) resins can remove natural organic matter (NOM) from drinking water sources. However, the IEX system produces a waste brine rich of sodium, chloride, NOM and sulfate. The treatment of the waste brine aims to recover a clean solution rich of sodium chloride, that can be reused to regenerate IEX resin. Previous research showed that ceramic nanofiltration partially removes NOM from the waste brine, but sulfate removal requires additional treatment. Sulfate removal by chemical precipitation was previously studied either on brines with low NOM concentrations or water with low concentrations of NOM and salts. The current work focussed on sulfate removal from NOM-rich brines by chemical dosing of (1) BaCl2, resulting in precipitation of barite (BaSO4), and (2) CaCl2, Ca(OH)2 and NaAlO2, resulting in precipitation of calcium sulfate and, subsequently, ettringite (Ca6Al2(SO4)3(OH)12). Additionally, the effect of NOM on SO42− removal was studied. Modelling and batch experiments were conducted with IEX and synthetic brines within the typical ion strength range of 0.1 to 1 M. With doses of 2.2 g of BaCl2 per g of initial sulfate, BaSO4 precipitation removed more than 83 percent of sulfate, resulting in final concentrations below 0.4 g/L even in the presence of NOM. However, NOM inhibited the precipitation of calcium sulfate and, subsequently, ettringite. With doses of 1.3 g of CaCl2, 0.5–0.7 g of Ca(OH)2 and 0.4–0.6 g of NaAlO2 per g of initial sulfate, calcium sulfate and ettringite precipitation removed between 8 and 95 percent of sulfate from NOM-rich brines, resulting in final concentrations between 0.8 and 2 g/L. As a reference, NOM-free brines required doses of 1.3 g of CaCl2, 0.2–0.7 g of Ca(OH)2 and 0.1–0.6 g of NaAlO2 per g of initial sulfate for 89 to 99 percent of sulfate removal, resulting in final concentrations of 0.2 g/L. The inhibition might be attributed to covering of crystal sites by NOM molecules, and to NOM coagulation with aluminium.

Designing a\xa0next generation solar crystallizer for real seawater brine treatment with zero liquid discharge

Proper disposal of industrial brine has been a critical environmental challenge. Zero liquid discharge (ZLD) brine treatment holds great promise to the brine disposal, but its application is limited by the intensive energy consumption of its crystallization process. Here we propose a new strategy that employs an advanced solar crystallizer coupled with a salt crystallization inhibitor to eliminate highly concentrated waste brine. The rationally designed solar crystallizer exhibited a high water evaporation rate of 2.42 kg m−2 h−1 under one sun illumination when treating real concentrated seawater reverse osmosis (SWRO) brine (21.6 wt%). The solar crystallizer array showed an even higher water evaporation rate of 48.0 kg m−2 per day in the outdoor field test, suggesting a great potential for practical application. The solar crystallizer design and the salt crystallization inhibition strategy proposed and confirmed in this work provide a low-cost and sustainable solution for industrial brine disposal with ZLD.

Evaluation of mortar produced with boiler blowdown brine

During boiler operation the concentration of water impurities can cause harmful effects such as scale deposits, corrosion, and embrittlement. Periodic water removal (blowdown) is necessary to maintain boiler operation, but introduces the problem of how to manage the waste brine material. This study explores the utilization of a simulated boiler blowdown brine for incorporation into cement-based materials, particularly for non-structural applications like cemented backfill. General use limestone (GUL) cement, and an ordinary Portland cement (OPC) were employed as binders in mortar mixtures, along with additional mortar mixtures where a portion of the binder was replaced with sodium silicate and waste brine. Compressive strength and electrical resistivity were monitored over time, along with thin section microscopy of the hardened mortar mixtures. Moreover, a monolithic leaching test was performed to assess nitrate leaching. The results indicate that blowdown brine that has been pre-treated with sodium silicate can be feasibly used to develop cemented backfill mixtures. A good linear correlation between the measured electrical resistivity and compressive strength test results is established for all mortar mixes. Cumulative nitrate leached from brine mortar mixtures were lower than 40 mg/L. Microscopic observations illustrate that the porosity was lower for mortars made with OPC. Optical and scanning electron microscope analyses show mm scale pockets of the sodium silicate waste brine mixture distributed within the paste fraction.

Selective electrochemical separation and recovery of calcium and magnesium from brine

Desalination via reverse osmosis (RO) generates a stream of fresh water and an almost equivalent volume of highly concentrated brine as waste. The waste brine is usually disposed back to the sea which increases the sea salinity in a way that can affect the marine life. Treatment of this waste brine is vital for the environment. The treatment process can be made feasible by extracting value added products from this waste brine. In this context, the current study demonstrates a novel two-step electrochemical process for selective separation and recovery of calcium and magnesium from brine. The first step involves purging carbon dioxide in the brine solution while electrochemically precipitating calcite using titania coated graphite cathode and pristine graphite anode at an applied potential of 2.5 V. The use of titania coated surface was found to be effective in promoting selective calcite precipitation. After calcite removal, brucite is selectively precipitated using pristine graphite cathode and anode at an applied potential of 3.5 V. This study also reveals the importance of DC potential and the electrode material for selective precipitation of calcium and magnesium ions from brine. Ion chromatography was used to analyze the concentration of calcium and magnesium ions in the treated and non-treated brine. X-ray diffraction and scanning electron microscopy of electrode precipitates confirmed the removal of calcium and magnesium from brine as calcite and brucite, respectively. Besides reducing the brine salinity, the developed process yields two separate compounds which can be further converted into calcium and magnesium-based products for several commercial applications.

Decreasing waste brine volume from anion exchange with nanofiltration: implications for multiple treatment cycles

Ion exchange (IX) removes hexavalent chromium from water, but waste brine disposal makes implementation cost-prohibitive in many communities. Nanofiltration treats waste brine for reuse in the next regeneration cycle.

Energy evaluation for separation methods of pure magnesium chloride hexahydrate from waste brine in CCU process

Energy evaluation for separation methods of pure magnesium chloride hexahydrate from waste brine in CCU process

Removal of natural organic matter by ion exchange: Comparing regenerated and non-regenerated columns

Dissolved organic matter (DOM) in water has adverse impacts on the water treatment process and is effectively removed by ion exchange (IEX). Some researchers have proposed the term biological ion exchange (BIEX) for the process of continuous DOM removal by ion exchange without the need for chemical regeneration that results in brine waste. Surface water with moderate dissolved organic carbon (DOC) concentrations (4–6 mg/L) and high sulfate concentrations (80 – 120 mg/L) was fed to two regenerated and two non-regenerated columns for 12,500 bed volumes (9 months) with the goal of investigating the effects of chemical and possibly biological regeneration on long-term IEX operation. Chemically regenerated columns achieved between 60 and 80% DOC removal for the entirety of the experiment, while non-regenerated columns achieved steady DOC removal of ~50%. Inorganic ion analysis showed that biological activity had minimal impact on DOC removal, and the main mechanism of removal was secondary IEX between sulfate (SO42−) and fractions of DOC with high affinities for ion exchange. Fluorescence and specific UV absorbance at 254 nm (SUVA 254) data showed that fractions of DOC with higher SUVA 254 values (terrestrial-like fractions) were better removed by secondary IEX than those with lower SUVA 254 values (aquatic/microbial-like fractions). Scanning electron microscopy showed that biofilms on non-regenerated resins covered 5–15% of the resin surface and are composed of numerous species of bacteria with varying functions, with some protozoa present.

Electrochemical precipitation to reduce waste brine salinity

Desalination of seawater is becoming the main process to produce fresh water in many countries. Waste brine or concentrate rejects are leftovers of the desalination process and can have an adverse impact on the environment due to its high salinity. In this study we show a facile process to reduce the salinity of concentrated brine and at the same time produce a value-added product, namely calcium and magnesium oxides. An electrochemical system is used to precipitates inorganic salts available in seawater brine. The system consists of two graphite electrodes, a DC power source and the waste-brine works as the electrolyte. The DC potential applied reduces water to hydroxyl ions which reduces the ionic species in the waste-brine. With an applied potential in the range of 2.5–4.0 V for 3 h time interval, the TDS of the brine solution reduces from 47,000 ppm to 42,000 ppm. Ion chromatography results indicate that there is a decrease in the Mg2+ and Ca2+ cations and chloride anion in the treated brine. X-ray diffraction data of the calcinated precipitates showed peaks for mainly magnesium oxide and calcium oxide.

Forward Osmosis as Concentration Process: Review of Opportunities and Challenges.

In the past few years, osmotic membrane systems, such as forward osmosis (FO), have gained popularity as “soft” concentration processes. FO has unique properties by combining high rejection rate and low fouling propensity and can be operated without significant pressure or temperature gradient, and therefore can be considered as a potential candidate for a broad range of concentration applications where current technologies still suffer from critical limitations. This review extensively compiles and critically assesses recent considerations of FO as a concentration process for applications, including food and beverages, organics value added compounds, water reuse and nutrients recovery, treatment of waste streams and brine management. Specific requirements for the concentration process regarding the evaluation of concentration factor, modules and design and process operation, draw selection and fouling aspects are also described. Encouraging potential is demonstrated to concentrate streams more than 20-fold with high rejection rate of most compounds and preservation of added value products. For applications dealing with highly concentrated or complex streams, FO still features lower propensity to fouling compared to other membranes technologies along with good versatility and robustness. However, further assessments on lab and pilot scales are expected to better define the achievable concentration factor, rejection and effective concentration of valuable compounds and to clearly demonstrate process limitations (such as fouling or clogging) when reaching high concentration rate. Another important consideration is the draw solution selection and its recovery that should be in line with application needs (i.e., food compatible draw for food and beverage applications, high osmotic pressure for brine management, etc.) and be economically competitive.

Environmental impact of desalination technologies: A review

Due to the limited availability of freshwater supplies, desalination has become an increasingly reliable process for water supply worldwide, with proved technical and economic feasibility and advantages. Recently, desalination capacity significantly increased from approximately 35 million m3 daily (MCM/day) in 2005 to about 95 MCM/day in 2018. Seawater desalination accounts for about 61% of global desalination capacity, while brackish water desalination accounts for 30%. Membrane desalination, mainly using reverse osmosis (RO), accounts for ¾ of global desalination capacity, with the rest mostly used for thermal desalination using multi-stage flash distillation (MSF), and multi-effect distillation (MED). Despite the undeniable role of desalination for securing water supply in areas where natural freshwater supplies are scarce, desalination impacts the natural environment at different aspects. Environmental impacts (EIs) of the desalination process are different and vary significantly according to the nature of the utilized feedwater, the desalination technology in use, and the management of waste brine generated. In this work, the EIs of each desalination technology were thoroughly investigated, with careful consideration given to different feedwater qualities, and various brine management techniques. Although the different aspects of desalination EIs have been extensively studied in the literature, the literature lacks comprehensive reviews and summaries of all the associated EIs. This article compiles the different EIs associated with the whole desalination process in one-hub, applying an intake-to-outfall approach. The leading desalination technologies of RO, MSF, and MED were analyzed, along with different feedwaters. This article provides a mapping of the different technologies involving feedwater and brine management techniques and a detailed description of their impact on the environment. Finally, recommendations and conclusions were given to minimize the negative impacts of desalination on both the local and global environments.

Long-Term Performance of a Pilot Scale Combined Chemical Precipitation-Ultrafiltration Technique for Waste Brine Regeneration at Chevron Steam Flooding Plant

In this work, chemical precipitation-ultrafiltration (UF) was applied for waste brine regeneration from a steam flooding plant at Duri Field, Chevron. A mixture of sodium hydroxide and sodium carbonate solution was used as chemical agent. A polypropylene (PP) UF membrane was used to remove precipitate formed in the chemical precipitation. It was found that the combined process could be used to regenerate waste brine, removing up to 100% ( ± 0.1) of calcium and up to 99.6% ( ± 0.3) of magnesium. High hardness removal was achieved when the chemical dosage was 1.3 to 1.7 mole of chemical/mole of hardness. Rapid permeability decline was observed in the UF membrane due to the high turbidity and TSS values of the chemically treated waste brine. Backwash with an acid solution could recover the UF membrane’s permeability effectively. However, pH adjustment is needed due to the high pH value of the UF permeate (up to ~12).

Management of By-Product Created by Lye-Sodium Brine Purification Method Using Carbonization

The article presents carbonization as a method of waste management from the brine sodium-lime method. It was compared with the previously obtained results for the lye-sodium one. Within it, the fltration and washing times were contrasted for treated and non-carbonised samples. For this aim potentiometric titration analysis was used to determine the precipitation's basic components and by-product brine. Scanning electron microscope with energy dispersive X-ray spectrum and diffractographic analysis were used for morphology analysis what allowed to determine the tested samples' composition. It was found that despite significant differences in the time of washing and filtration, the time of these processes is shortened after the suspension has been exposed to carbon dioxide. In both cases the composition allows the waste brine to be recycled to the purifcation processes and the mixture of calcium and magnesium compounds become alternative raw material. It turned out that in both methods it is possible to utilize the suspension formed.

Techno-economic analysis of multi-stage ion concentration polarization with recirculation for treatment of oil produced water

The concept of recirculation of diluate/concentrate stream is implemented in multi-stage ion concentration polarization (ICP) desalination to deal with the issue of uncontrolled concentrate streams and deteriorated overall recovery rate to treat highly concentrated oil produce water from refineries. An improved empirical optimization model was established to calculate total energy consumption for operating cost and required membrane area for capital cost for a given set of operating parameters, feed salinity, salt removal ratio, and flow velocity. Using the empirical optimization model, a techno-economic analysis is performed to evaluate the feasibility of two-stage ICP system with recirculation loops. Brine of 160 g/kg is set as the system feed stream, whereas other operating conditions such as dilaute and concentrate streams are being controlled/fixed with 20 g/kg and ~250 g/kg respectively. Also, the system can be flexibly controlled to produce a specific concentration of product water and a recovery ratio with a corresponding water cost. With careful choices of recirculation rates, one can significantly increase the recovery ratio of two-stage ICP brine treatment process (from 25% to 39%) with only minor increase in overall cost (from $16.4–25.9/m3 to $20.6–22.54/m3), which is favourable for brine waste treatment application.

Photochemical removal of hexavalent chromium and nitrate from ion-exchange brine waste using carbon-centered radicals

Ion-exchange (IX) is a promising technology to remove hexavalent chromium Cr(VI) and nitrate from groundwater; however, its wide application is challenged by a costly disposal of spent brine. This study developed a novel photochemical process utilizing reductive carbon-centered radicals to remove Cr(VI) and nitrate in IX spent brine. In the presence of formate or alcohol additives, photolysis of nitrate in spent brine generated highly reductive carbon-centered radicals including ·CO2−, ·CH2OH, ·CH(OH)CH3, and ·C(OH)(CH3)2. Among them, ·CO2− exhibited the highest efficiency to reduce Cr(VI) to non-toxic Cr(III) solids. Increasing the dosage of formate additive promoted ·CO2− production and accelerated Cr(VI) removal. Decreasing pH enhanced Cr(VI) removal by increasing the yield of ·CO2− and thermodynamic favorability of Cr(VI) reduction while lowering total chromium removal because of the formation of soluble Cr(III) species. High levels of chloride in spent brine scavenged HO·, suppressed ·CO2− production, and inhibited Cr(VI) reduction. With an extended reaction time, nitrate was photochemically converted to gaseous nitrogen species. The denitrification process was favored at acidic pH due to the suppressed formation of nitrite. Findings from this study provides a new photochemical treatment technology for hazardous IX spent brine management.

Effect of brine mass rate on pressure drop and dirt factor in evaporator design

Geothermal is one of the most significant natural resource potentials in Indonesia. One power plant that utilises geothermal steam as its energy source is PLTP. Geothermal steam that has passed through the geothermal power plant separator to move the turbine while the residual waste (brine) with a high enough temperature has the potential to be a source of heating to produce electrical energy in the Kalina cycle generator. Using brine, before entering the turbine, it must first become airtight in the evaporator. Evaporator design requires initial parameters namely brine fluid flow rate and ammonia-water flow rate, shell dimensions and tube dimensions as well as the number of passes, then performs the design calculation steps until the calculation results meet operating requirements, namely the pressure drop value and the dirt factor. Different variations of brine rate will produce different pressure drops and soil factors. Brine rate variations are 11 kg/s, 22 kg/s, 33 kg/s, 44 kg/s, 55 kg/s and 66 kg/s show the lowest pressure drop of 0.098 bar and the most massive 0.68 bar, and the smallest dirt factor is 0,002 (hr)(m2 °C)/Joule moreover, the largest is 0,00019 (hr)( m2 °C)/Joule.

Application of Partial Nitritation-Anammox（PN-AX）Process to Treatment of Waste Brine from Natural Gas Plant : From Lab to Full Scale Plant

Application of Partial Nitritation-Anammox（PN-AX）Process to Treatment of Waste Brine from Natural Gas Plant : From Lab to Full Scale Plant