Crop Residue Removal: Assessment of Future Bioenergy Generation Potential and Agro-Environmental Limitations Based on a Case Study of Ukraine

Exploring agricultural waste biomass for energy, food and feed production and pollution mitigation: A review

Globally agricultural production system generates a huge amount of solid waste. Improper agri-waste management causes environmental pollution which resulted in economic losses and human health-related problems. Hence, there is an urgent need to design and develop eco-friendly, cost-effective, and socially acceptable agri-waste management technologies. Agri-waste has high energy conversion efficiency as compared to fossil fuel-based energy generation materials. Agri-waste can potentially be exploited for the production of second-generation biofuels. However, composted agri-waste can be an alternative to energy-intensive chemical fertilizers in organic production systems. Furthermore, value-added agri-waste can be a potential feedstock for livestock and industrial products. But comprehensive information concerning agri-waste management is lacking in the literature. Therefore, the present study reviewed the latest advancements in efficient agri-waste management technologies. This latest review will help the researchers and policy planners to formulate environmentally robust residue management practices for achieving a green economy in the agricultural production sector.

Economic Feasibility of Agricultural Biogas Production by Farms in Ukraine

Renewable energy generation in Ukraine is developing slower than state strategies and expectations, with the installations for energy generation based on biogas currently being among the lowest in terms of installed capacity. Most of those involved in energy generation from agricultural biogas are large enterprises, while the small and medium-sized farms are far less involved. Thus the article aims to assess the economic feasibility of biogas production from agricultural waste by specific farm types and sizes, with a special focus on small and medium-sized farms. The research results present findings in two dimensions, first defining the economic feasibility of biogas installations in Ukraine based on investment costs and the rate of return at both the current and potential feed-in tariff, and second, analyzing the influence of state regulation and support on the economic feasibility of agricultural biogas production in Ukraine. The results emphasize that the construction of small generation capacities does not provide sufficient funds under the current feed-in tariff to meet the simple return period expected by the domestic financing institutions. Except for the general support programs for agricultural activities, there are no support funds specifically for biogas producers, while there is tight competition with wind and solar energy due to diversified feed-in tariffs.

Feeding value of sorghum stover fed to tropical hair sheep as complete rations in chop, mash, pellet, and block forms

Background and Aim:

Poor palatability, low bulk density, and low nutritive value restrict the utilization of the crop residues as animal feeds. Altering the physical characteristics of feed by blending the roughage and concentrates in the form of complete feed improves the nutrient use efficiency and reduces the feed wastage, feed cost, and labor cost. The study aims to determine suitable processing methods (mash, pellet, or block forms) for efficient utilization of sorghum stover-based complete rations vis-a-vis conventional feeding methods in sheep.

Materials and Methods:

The sorghum stover was incorporated in complete rations with roughage to concentrate ratio of 50:50 proportion in a growth trial of 120 days. The feed ingredients were chaffed, ground in a hammer mill, passed through expander-extruder, and compressed by feed block machine to prepare chop, mash, pellet, and block form of rations, respectively. Twenty-four male intact growing Nellore×Deccani cross lambs (3.5±0.5 months age, 14.50±0.41 kg (mean ± SD) at the start of the experiment) were divided into four experimental groups of six animals each in a complete randomized design. The experimental rations were randomly allotted to each group and evaluated for their intake, nutrient utilization, and growth performance.

Results:

The sheep fed on pellet-based ration consumed a higher (p<0.05) quantity of dry matter. The digestibility coefficients of organic matter, crude protein, and neutral detergent fiber were higher (p<0.05) in processed rations (mash, pellet, or block). Further, the nitrogen balance (g/d) was higher (p<0.05) in the mash, pellet, and block form of rations, compared to chopped ration. The processing method did not influence calcium or phosphorous balance parameters, except for their urinary losses, which showed an increasing trend (p=0.07). The ram lambs fed with pelleted ration showed higher (p<0.05) weight gain than mash, block, or chaff forms. The efficiency of feed utilization in gaining one kg body weight was higher (p<0.05) in lambs fed a pelleted diet. Feeding pelletized ration was more economical to gain one kg body weight. The bulk density was highest for block-based ration followed by pellet, mash, and conventional rations, and the carrying capacity of truck was highest with the least transport cost in block-form of rations.

Conclusion:

Physical processing (mash, pellet, and block) of sorghum stover-based complete rations increased the nutrient utilization and growth performance of sheep compared to conventional chopped form. Pelleting the mash with expander-extruder procedure was found to be more profitable. Nevertheless, the cost economics revealed blocks as more preferable forms for transporting the complete rations to larger distances.