A spacer array including a plurality of spacers. Each spacer defines a longitudinal axis and includes a main body, a leading pin, and a trailing pin. The main body has a main body cross-sectional dimension. The leading pin extends from the main body and is upstream of the main body. The leading pin has a leading pin cross-sectional dimension. The trailing pin extends from the main body and is downstream of the main body. The trailing pin has a trailing pin cross-sectional dimension. The main body cross-sectional dimension is greater than the leading pin cross-sectional dimension and the trailing pin cross-sectional dimension.

A floating support grid system including a plurality of support beams and a plurality of profile wire screen panels wherein the support beams are connected to the profile wire screen panels via one or more first floating connections, wherein the support beams are configured to connect to a horizontal ammonia converter basket via one or more second floating connections, and wherein at least some the profile wire screen panels are configured to connect to a horizontal ammonia converter basket via one or more third floating connections, wherein each of the first, second, and third floating connections independently defines one or more gaps to accommodate movement caused by thermal expansion.