In recent times, the escalation of greenhouse gases, air pollution and depletion of the ozone layer has enforced the researchers to renovate the regular use of fossil fuels into alternate methods which are non-toxic, eco-friendly, and cost-effective. Biomass is one of the traditions to swap fossil fuels. Biomass can be transmogrified into beneficial and eco-friendly forms of energy under various conversion processes. The obtained energy can be used for heating water, industrial heating process, and generating electricity. Pyrolysis is a method to alter biomass into useful products, as the final yields of this process include bio-oil, char, methane (CH4), hydrogen (H2), carbon monoxide (CO) and carbon dioxide (CO2). It is well known for its high efficiency and environmental performance. In this method even the agricultural residues, waste woods, solid municipal waste, plant wastes can be utilized. This review comprehends the various concepts on products of biomass pyrolysis, mechanisms, and several pre-treatment processes used for efficient pyrolysis of biomass have been analysed. The impact of various fundamental constraints such as temperature, heating rate, particle size was studied and their influence on yield and composition were studied.

This study investigates the potential of a blended binder formulated from two industrial solid wastes viz. phosphogypsum and fly ash in combination with lime. Three mix proportions of phosphogypsum and fly ash were investigated, and the minimum lime contents required for activation were determined using the Eades and Grim pH test. The lime–fly ash–phosphogypsum blends were then cast into cubes, both in their paste form as well as mortar form, mixed with sand in the ratio of 1:3. They were cured for a period of seven days, and afterwards, their compressive strength was determined. Ordinary Portland cement and lime mortar blocks were also cast as control specimens for comparative evaluation of the strength. The optimal lime–fly ash–phosphogypsum blend was identified and used to construct a masonry prism, and the strengths of the masonry prisms were also evaluated. The optimal lime–fly ash–phosphogypsum blend mortar was also subjected to an X-ray diffraction analysis to determine the reaction products formed during hydration. The study revealed that 5% lime mixed with fly ash:phosphogypsum in the ratio of 3:1 was the optimal proportion which gave the maximum strength to the cubes. The optimal lime–fly ash–phosphogypsum blend mortar developed strength that was higher than conventional Portland cement and lime mortar. The optimal lime–fly ash–phosphogypsum blend mortar masonry prisms developed strength that was comparable to that of Portland cement mortar masonry. The X-ray diffraction analysis revealed the formation of calcium silicate hydrate minerals as well as ettringite and portlandite which were responsible for strength gain.