Abstract: A horizontal scrubber may be configured for removal of sulfur dioxide and particulate matter from a gaseous stream derived from the combustion of biomass, including, for example, sugar cane bagasse. The scrubber may include a horizontally disposed housing including an inlet configured to receive a gas stream derived from combusted biomass and an outlet. The scrubber may further include a manifold of liquid nozzles disposed within the housing that are configured to provide a spray of liquid droplets in a co-current orientation to the gas stream. An array of tubes may be oriented adjacent to the manifold of liquid nozzles and may be configured to receive the gas stream and liquid droplets from the nozzle array, but providing minimal resistance to material flow. To encourage flow, members of the tube array may include circular walls with a substantially uniform cross section.