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Biochars are emerging eco-friendly products showing outstanding properties in areas such as carbon sequestration, soil amendment, bioremediation, biocomposites, and bioenergy. These interesting materials can be synthesized from a wide variety of waste-derived sources, including lignocellulosic biomass wastes, manure and sewage sludge. In this work, abundant data on biochars produced from coconut-shell wastes obtained from the Colombian Pacific Coast are presented. Biochar synthesis was performed varying the temperature (in the range: 280 °C–420 °C) and O2 feeding (in the range: 0–5% v/v) in the pyrolysis reaction. Production yields and some biochar properties such as particle size, Zeta Potential, elemental content (C, N, Al, B, Ca, Cu, Fe, K, Li, Mg, Mn, Na, P, S, Ti, Zn), BET surface area, FT-IR spectrum, XRD spectrum, and SEM morphology are presented. This data set is a comprehensive resource to gain a further understanding of biochars, and is a valuable tool for addressing the strategic exploitation of the multiple benefits they have. © 2019 The Author(s) Universidad del Valle, Univalle: CIAM-2017 Departamento Administrativo de Ciencia, Tecnología e Innovación (COLCIENCIAS), COLCIENCIAS

Centrifugation is a commonly applied separation method for manure processing on large farms to separate solids and nutrients. Pathogen reduction is also an important consideration for managing manure. Appropriate treatment reduces risks from pathogen exposure when manure is used as soil amendments or the processed liquid stream is recycled to flush the barn. This study investigated the effects of centrifugation and polymer addition on bacterial indicator removal from the liquid fraction of manure slurries. Farm samples were taken from a manure centrifuge processing system. There were negligible changes of quantified pathogen indicator concentrations in the low-solids centrate compared to the influent slurry. To study if possible improvements could be made to the system, lab scale experiments were performed investigating a range of g-forces and flocculating polymer addition. The results demonstrated that polymer addition had a negligible effect on the indicator bacteria levels when centrifuged at high g forces. However, the higher g force centrifugation was capable of reducing bacterial indicator levels up to two-log10 in the liquid stream of the manure, although at speeds higher than typical centrifuge operations currently used for manure processing applications. This study suggests manure centrifuge equipment could be redesigned to provide pathogen reduction to meet emerging issues, such as zoonotic pathogen control.

The traditional method to refine crude cottonseed oil is time-consuming and expensive. This study evaluates the effectiveness of coagulation–flocculation–sedimentation process using quaternary polyamine-based polymers in refining crude cottonseed oil. Flocculated by four commercial polyamine-based cationic polymers (SL2700, SL3000, SL4500 and SL5000) with varied molecular weight (MW) and charge density (CD) and followed by coagulation with sodium hydroxide, crude cottonseed oil can be effectively purified. Free fatty acids, gossypol, pigments and trace elements are all effectively and sufficiently removed by the four polymers in a MW- and CD-dependent manner. Our results suggest that the use of polyamine-based cationic polymers may offer an effective and feasible alternative to the traditional method for crude cottonseed oil refining.

We have determined that X-ray fluorescence (XRF) spectrometry can be used as a rapid and precise method for quantitative elemental analysis of macro and micro nutrients in dairy manure. The elements chosen for this study were N, P, K, Ca, Mg, S, Zn, Mn, Fe, Cu, Al, Na, B, and C. The wavelength-dispersive XRF spectrometer was calibrated by comparing its results with a panel of dried dairy manure samples with analyses from inductively coupled plasma (ICP) obtained from three independent certified laboratories. In addition, the XRF results for C, N, and S were compared with those from a high-temperature combustion (HTC) analyzer dedicated to measurements of these three elements. Then the performance of the calibrated XRF was tested against a separate panel of dairy manure samples collected at fifteen different sampling points at a manure processing plant. Subsamples from these samples were analyzed for the 14 elements of interest by a certified laboratory. The close agreement between the XRF results and those of the certified laboratory established that XRF can be used as a simple and precise method for the elemental analysis of dairy manure

High phosphorus (P) content of animal feed coproducts of dry grind corn ethanol plants can lead to dietary P levels that are incompatible with P-based nutrient management plans. Therefore, treatment of thin stillage, the dominant P contributor of coproducts, was investigated using centrifugation followed by chemical treatment with coagulants (lime, alum, ACH) and flocculants (anionic and cationic polymers). The majority of the P and solids in thin stillage are in the dissolved form (

Controlling erosion, reestablishing vegetation, and overcoming the negative effects of hydrophobic soils has long been a challenge following catastrophic wildfire on forested lands and rangelands. A three-year controlled study was recently completed to compare polyacrylamide soil treatment to the traditional cover method using agricultural straw on high severity burned soils of the Red Bull Fire, which burned through the Uinta National Forest near Provo, Utah, in July and August of 2004. Weed free, recycled paper pellets containing polyacrylamide were found to be an effective Burn Area Emergency Rehabilitation treatment option on clay rich soils containing divalent cations (i.e., Ca2+) within the soil matrix. This study showed aerial application of the granular polyacrylamide pellets resulted in an even distribution of the polymer-based product on the soil surface. Through water activation, a blend of water-soluble linear anionic polyacrylamide copolymers are slowly released, which bind with the soil particles, structurally stabilizing the soil. When compared to agricultural straw, polyacrylamide results show improved revegetation, reduced soil hydrophobicity, and reduced soil erosion.

The summertime heating of runoff in urban areas is recognized as a common and consistent urban climatological phenomenon. In this study, a simple thermal urban runoff model (TURM) is presented for the net energy flux at the impervious surfaces of urban areas to account for the heat transferred to runoff. The first step in developing TURM consists of calculating the various factors that control how urban impervious areas absorb heat and transfer it to moving water on the surface. The runoff temperature is determined based on the interactions of the physical characteristics of the impervious areas, the weather, and the heat transfer between the moving film of runoff and the impervious surface common in urban areas. Key surface and weather factors that affect runoff temperature predictions are type of impervious surface, air temperature, humidity, solar radiation before and during rain, rainfall intensity, and rainfall temperature. Runoff from pervious areas is considered separately and estimated using the Green-Ampt Mein-Larson rainfall excess method. Pervious runoff temperature is estimated as the rainfall temperature. Field measurements indicate that wet bulb temperature can be used as a surrogate for rainfall temperature and that runoff temperatures from sod average just 2°C higher than rainfall temperatures. Differences between measured and predicted impervious runoff temperature average approximately 2°C, indicating that TURM is a useful tool for determining runoff temperatures for typical urban areas.

Impervious surfaces absorb and store energy from the sun. During a rainfall/runoff event, some of that energy is transferred to the runoff as it flows over heated impervious surfaces. High-temperature runoff can be detrimental to cold-water habitat as it enters receiving waters; therefore, structures to cool this heated runoff water are desirable. Rock cribs are underground trenches that stormwater runoff flows through prior to discharging into receiving waters or storm sewers. Since the crib is below the ground surface, its initial temperature is significantly lower than that of the incoming stormwater runoff. Heat is transferred from the higher-temperature influent water to the cooler rocks and water in the crib, reducing the effluent temperature. In this article, we present a thermal mixing model to predict the conductive cooling effect of rock cribs. Two key simplifications were made in order to model this system: (1) laboratory measurements of an empirical mixing function were used to relate predicted mean crib temperatures to crib outlet temperatures, and (2) transient heat conduction from spheres occurs with an effective depth into the sphere of one-tenth of the rock diameter such that transient one-dimensional heat conduction applies. Results from a laboratory study were used to evaluate the simplifications and test the model. Comparisons between model results and experimental measurements showed that the thermal mixing model assumptions were satisfactory. A non-dimensional, graphical look-up approach is proposed for urban engineers to size rock cribs and implement a viable management practice for reducing urban runoff temperature.

Three relatively new applications for controlling wind and water erosion using polyacrylamide copolymers are described that take advantage of their ability to stabilize and add structure to soil. In the first application, low concentrations of anionic, high purity polyacrylamide (PAM) eliminates sediment in runoff water by more than 90% when added to irrigation water at 10 ppm , or at a rate of 1 to 2 kg ha−1 per irrigation. Lab-furrow tests were utilized to characterize the role of molecular weight, charge, and ion concentrations in applying PAM during irrigation. In the second application, PAM is applied at construction sites and road cuts at rates of 22.5 kg ha−2 (tenfold higher rates than in irrigation control) resulting in reduction in sediment runoff by 60–85% during (simulated) heavy rains. Finally, a formulation of PAM mixed with aluminum chlorohydrate and cross-linked poly(acrylic acid) superabsorbent at a ratio of (6:1:1) has been applied to create helicopter landing pads that minimize dust clou...

Soil erosion from agricultural lands and the subsequent transport of sediment and sediment-bound nutrients (particularly P) are serious problems contributing to surface water pollution and threatening agricultural sustainability. Raindrop impact on bare soil destabilizes soil aggregates and leads to surface sealing, increasing runoff volumes and soil loss. Surface-applied polyacrylamide (PAM) decreases soil erosion by stabilizing the soil structure and reducing surface sealing. Previous research has shown that surface-applied PAM reduces erosion at relatively high application rates (20 to 80 kg ha-1). The purpose of this study was to evaluate the effectiveness and longevity of a new liquid/emulsion PAM formulation to reduce runoff, sediment, and P loss from rainfed agricultural fields. The formulation was applied using a hand sprayer at a low PAM rate of 5 kg ha-1 (13,333 L of solution ha-1). Plot-scale field rainfall simulations (75 mm h-1) were conducted on individual test plots at three test intervals (rainfall simulated 2 days, 3 weeks, and 10 weeks after PAM application) on two soil types (Ashdale silt loam and Plano silt loam). The new polymer formulation, Soil Net EM-1000-50, reduced runoff volumes an average of 100% at the 2-day test interval, 59% at the 3-week test interval, and 55% at the 10-week test interval. Overall, larger rainfall depths were applied to treatment plots prior to runoff generation compared to controls. The most significant differences were observed at the 2-day test interval, when an average of 141 mm of rainfall was applied to the PAM-treated plots before runoff started, compared to 82 mm for the controls. These runoff reductions are not only important in terms of erosion but may also enhance water supply through increased infiltration. Sediment loss was reduced an average of 100% at the 2-day test interval, 80% at the 3-week test interval, and 74% at the 10-week test interval. Phosphorus loss was reduced an average of 100% at the 2-day test interval, 75% at the 3-week test interval, and 83% at the 10-week test interval. The polymer treatment was more effective on the Ashdale silt loam, which had received manure during the two years preceding the rainfall simulations. Manure application was the primary difference between the two soils (manure was not applied to the Plano silt loam), suggesting that the PAM treatment reacts more favorably to manured soils. The low cost of this new PAM technology (approx. $25 ha-1) coupled with its success in reducing runoff, sediment, and P loss over a 10-week period, make EM-1000-50 an attractive and economically feasible management practice for agricultural producers in rainfed regions.

An Erosion Control and Stormwater Management Ordinance was recently adopted in Dane County, Wisconsin, U.S.A. The thermal control section of this ordinance is…

Background The current higher manufacturing cost of biofuels production from lignocellulosics hinders the commercial process development. Although many approaches for reducing the manufacturing cost of cellulosic biofuels may be considered, the use of less expensive feedstocks may represent the largest impact. In the present study, we investigated the use of a low cost feedstock: post-biogas digestion dairy manure fiber. We used an innovative pretreatment procedure that combines dilute sodium hydroxide with supplementary aqueous ammonia, with the goal of releasing fermentable sugar for ethanol fermentation. Results Post-biogas digestion manure fiber were found to contain 41.1% total carbohydrates, 29.4% lignin, 13.7% ash, and 11.7% extractives on dry basis. Chemical treatment were applied using varying amounts of NaOH and NH3 (2-10% loadings of each alkali on dry solids) at mild conditions of 100°C for 5 min, which led to a reduction in lignin of 16-40%. Increasing treatment severity conditions to 121°C for 60 min improved delignification to 17-67%, but also solubilized significant amounts of the carbohydrates. A modified severity parameter model was used to determine the delignification efficiency of manure fiber during alkaline pretreatment. The linear model well predicted the experimental values of fiber delignification for all pretreatment methods (R2 > 0.94). Enzymatic digestion of the treated fibers attained 15-50% saccharification for the low severity treatment, whereas the high severity treatment achieved up to 2-fold higher saccharification. Pretreatment with NaOH alone at a variety of concentrations and temperatures provide low delignification levels of only 5 − 21% and low saccharification yields of 3 − 8%, whereas pretreatment with the combination of NaOH and NH3 improved delignification levels and saccharification yields 2–3.5 higher than pretreatment with NH3 alone. Additionally, the combined NaOH and NH3 pretreatment led to noticeable changes in fiber morphology as determined by SEM and CrI measurements. Conclusions We show that combined alkaline treatment by NaOH and NH3 improves the delignification and enzymatic digestibility of anaerobically digested manure fibers. Although pretreatment leads to acceptable saccharification for this low-cost feedstock, the high chemical consumption costs of the process likely will require recovery and reuse of the treatment chemicals, prior to this process being economically feasibility.