From: Paul Olivier
Date: Mon, 12 Nov 2018 at 17:26
Subject: street kitchens in Vietnam
A street kitchen in Vietnam is generally a grave threat to human health and the environment. A street kitchen typically burns coal, charcoal or firewood. The lighting of these solid fuels usually emits a cloud of black smoke. When these solids fuels are combusted, high levels of benzene, particulate matter and CO stream forth in all directions. But perhaps, still worse, are the highly carcinogenic cooking oil fuels.
Near the University of Dalat, there are several street kitchens close to one another. They emit large quantities of cooking oil fumes. These cooking oil fumes combine with particulate matter and nitrogen compounds (emitted by sewage lines), and when these pollutants enter the human lung, they stick there and do not come out. People get sick, and people die.
Here you see jpegs of a 150 gasifier equipped with a 3-sided wind shield, a 40-liter biochar filter, a hood and a fan.
The solid fuels typically used by street kitchens are costly. But with a gasifier, one has high-grade heat at a profit, since the biochar pellets produced in the gasifier have a greater value than the raw pellets from which they are derived. In other words, one has high-grade heat at a profit.
When biochar is produced in a gasifier, dirty and highly-polluting biochar kilns are not needed. In Dalat I have seen biochar kilns that emit, day after day, huge clouds of smoke.
Gasifiers can be powered almost entirely by agricultural waste biomass, such as rice hulls and rice straw. To the extent that such waste biomass would be pelleted and used as gasifier fuel, the useless burning of this waste would not take place.