Advanced oxidation processes in the removal of organic substances from produced water: Potential, configurations, and research needs

A critical review of risks, characteristics, and treatment strategies for potentially toxic elements in wastewater from shale gas extraction.

Enhanced electrokinetic remediation of hydrophobic organics contaminated soils by the combination of non-ionic and ionic surfactants

Oilfield produced water treatment by liquid-liquid extraction: A review

Polyacrylamides are often used in water-based hydraulic fracturing for natural gas and oil production. However, residual polymer remaining in the fractured rock can limit production. A novel approach for degrading partially hydrolyzed polyacrylamide (HPAM) was investigated using hydrogen peroxide and horseradish peroxidase (HRP). This sustainable HRP/H2O2 system degraded the polymer in solution, reducing its viscosity in both pure water and brine solutions. Molecular weight measurements confirmed that the viscosity reduction was due to a significant degradation of the polymer backbone and not primarily by other mechanisms such as amide hydrolysis or rearrangement, and so forth. The reduction in viscosity and molecular weight was first order with respect to H2O2 concentration. The kinetics of viscosity reduction and molecular weight are closely correlated which would allow the quicker and simpler viscosity method to help engineer future processes. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44560.

Enzymatic degradation of polyacrylamide in aqueous solution with peroxidase and H2O2

In this study, a combined process was developed that included flocculation, Fenton oxidation and sequencing batch reactor (SBR) to treat oilfield fracturing wastewater (FW). Flocculation and Fenton oxidation were applied to reduce chemical oxygen demand (COD) organic load and to enhance biodegradability, respectively. For flocculation, the optimum conditions were: polymeric aluminium chloride dosage, 40 mg/L; polyacrylamide dosage, 4 mg/L; dilution ratio, 1:2 and stirring time, 30 min. For Fenton oxidation, a total reaction time of 60 min, a H2O2 dosage of 2 m mol/L, with a [H2O2]/[FeSO4] ratio of 2 were selected to achieve optimum oxidation. Under these optimum flocculation and Fenton oxidation conditions, the COD removal efficiency was found to be 76.6%. Following pretreatment with flocculation and Fenton oxidation, the FW was further remediated using a SBR. Results show that COD was reduced to 92 mg/L, and the overall water quality of the final effluent could meet the class I national wastewater discha...

Treatment of oilfield fracturing wastewater by a sequential combination of flocculation, Fenton oxidation and SBR process

The invention discloses trichoderma capable of preventing and treating root rot of a loquat and belongs to the technical field of microorganisms. Preservation number of the trichoderma capable of preventing and treating the root rot of the loquat is CGMCC No.9390. The trichoderma has a strong antagonistic effect on pathogenic bacteria of the root rot of the loquat and can be used for preventing and treating the root rot of the loquat, and indoor inhibition ratio reaches up to 88%. A method for preventing and treating the root rot of the loquat by adopting the trichoderma comprises the following steps: culturing the trichoderma on a solid culture medium, punching a bacterium cake for later use by adopting a puncher, punching a hole in the phloem of a trunk of a loquat seedling by adopting the puncher in the same specification at the same time, and removing the phloem; placing the bacterium cake into the hole in the trunk, the phloem of which is removed, of the loquat, and sealing with a preservative film for moisturizing; or culturing the trichoderma in a liquid culture medium, diluting a bacterium solution with sterilize water, and irrigating each loquat for 500ml diluent at roots. The trichoderma disclosed by the invention can be used for effectively preventing and treating the root rot of the loquat, a prevention and control method is simple, the environment is not polluted, and growth of the loquat can be promoted.

Trichoderma capable of preventing and treating root rot of loquat

The invention discloses a preparation method of thichoderma composite germicide. The method comprises the steps that drug resistant trichoderma strains are cultured in a culture medium, when a culture dish is overgrown by spores, the spores are cleaned through sterile water, 0.8-1.2*10 /mL of spore suspending liquid is prepared, 80-120 mg/L of the germicide is added, and the trichoderma composite germicide is obtained. According to the preparation method of the thichoderma composite germicide, the technology is simple, and the obtained germicide is environmentally friendly.

Preparation method of trichoderma composite germicide

The invention discloses a multifunctional trichoderma strain LY3 and a preparation method for a bacterium agent of the multifunctional trichoderma strain. The strain is preserved, and the preservation number is 11125. The preparation method comprises the following steps that the LY3 trichoderma strain is cultured on a PDA culture medium at 28 DEG C for 5 d, prepared into spore liquid with the concentration of 1*106/mL through sterilized distilled water, the spore liquid is inoculated into a sterilized rice bran fermentation substrate at the rate of 7%, 0.5% of D-fructose, 1% of peptone, 0.5% of disodium hydrogen phosphate and 40% of tap water are added by mass, and then static culturing is performed at 30 DEG C through alternation of light and darkness for 11 d. The preparation method for the bacterium agent of the multifunctional trichoderma strain is simple in technology, and the prepared bacterium agent is environmentally friendly and simultaneously has the medicine-fertilizer dual-purpose advantage and the wide market prospect.

Multifunctional trichoderma strain LY3 and preparation method for bacterium agent of multifunctional trichoderma strain

The invention discloses a loquat endophytic unciform trichoderma strain and applications of the loquat endophytic unciform trichoderma strain. The endophytic trichoderma strain is obtained through separation, then morphological and molecular biological identification is carried out, meanwhile, the antibacterial activity of the endophytic trichoderma strain is tested, and thus a material is provided for the development and utilization of the strain; the endophytic trichoderma strain has the antibacterial activity for five phytopathogens, wherein the inhibiting effect for fungi is obviously stronger than that for bacteria, specifically, the inhibiting effect for pyricularia grisea is the strongest and is 83.17%, the antibacterial rate for alternaria tenuissima takes the second place and is 75.10%, the antibacterial rates for fusarium proliferatum and fusarium sambucinum have no obvious differences and are respectively 52.02% and 49.07%, and the antibacterial rate for Xanthomonas oryzae pv.oyzae is the poorest, and is 38.24%. The trichoderma strain has the antibacterial wide spectrum, and has the development and utilization values and prospects.

Liu Yanhong

Papers

Treatment of oilfield fracturing wastewater by a sequential combination of flocculation, Fenton oxidation and SBR process

Trichoderma capable of preventing and treating root rot of loquat

Preparation method of trichoderma composite germicide

Multifunctional trichoderma strain LY3 and preparation method for bacterium agent of multifunctional trichoderma strain

Loquat endophytic unciform trichoderma strain and applications thereof