Author: Muhammad Ahmad

One may consider a modern pulp and paper mill as a first‐generation forest biorefinery, with steam, power, and other products being produced alongside the wide range of paper products we normally associate with the industry. Black liquor and biomass gasification are key technology platforms for realizing the forest biorefinery of the future. Current research and…

A cost‐benefit analysis of BLG‐based bio‐refining in the kraft pulp and paper mill was studied by Larson et al. (2006a) and Consonni et al. (2009). The study assumed that BLG systems are technologically comparable with Tomlinson recovery boilers. Hence, BLGCC or bio‐refinery systems can be integrated within kraft pulp mill replacing the conventional recovery technology.…

Modern Tomlinson boilers are characterized by emissions of criteria pollutants that are similar overall to grid power (some are higher, like CO and PM, while others are lower, like SO2 and NOx). The most significant pollutants, in terms of both environmental impacts and relative emissions rates from Tomlinson boilers, are NOx and particulates. While many furnaces already have…

Water quality, temperature, and consumption are all potential concerns with biorefineries. Over time, as demand rises for limited freshwater supplies, these issues are likely to only become more important. Briefly, the issues are as follows: Depending on the configuration (amount of fuels and electricity produced), the biorefinery will have different effects on water quantity and…

Compared with FTL or DME synthesis, the technology for synthesis of methyl‐, ethyl‐, and propanol‐mixed alcohols (MA) is considerably less commercially advanced, and there is sparse published literature on which to base detailed reactor performance estimates. Catalysts that have been examined in the past can be divided into four categories (Liu et al. 1997): ruthenium‐based catalysts,…

The process is also known as supercritical water oxidation. This is a novel technology to produce methane‐rich synthesis gas as an alternative to replace the conventional recovery system (Naqvi et al. 2010). Heat demand for bringing water to supercritical conditions is less than that for evaporating at subcritical pressure. This phenomena leads to better energy savings…

Single‐step DME synthesis reactors typically utilize a mix of two catalysts, one promoting the synthesis of methanol from syngas (CO + 2H2 → CH3OH) and one promoting the dehydration of the methanol to DME (2CH3OH → CH3OCH3 + H2O). Both liquid‐phase and fixed‐bed reactors are offered commercially. Leading developers of liquid‐phase DME synthesis reactors are DME Development, Inc., a Japanese consortium of…

The conversion of clean synthesis gas into a liquid fuel involves passing the syngas over a catalyst that promotes the desired synthesis reactions and then refining the raw product to obtain the final desired liquid fuel. Two basic designs for commercial synthesis reactors have been developed: gas‐phase (or fixed‐bed) and liquid‐phase (or slurry‐bed). Fixed‐bed reactors…