斯里兰卡采购需求：硫酸铵晶体、硫酸铵颗粒、氯化铵、硫代硫酸铵、硝酸钙、硝酸钙颗粒

I'm looking for a reliable supplier of industrial-grade potassium carbonate. Could you provide the details on your availability and pricing? I'm interested in bulk quantities for production purposes, so it would be great to know about any minimum order requirements you might have. Additionally, please include information on your delivery timelines and whether you offer any support for shipping logistics. If you have certificates or specifications for quality assurance, that would be helpful too. I'm keen to establish a long-term partnership, so looking forward to your prompt response with the necessary details!